Et Tunc Nulla Erat VII

Et tunc nulla erat VII
(And Once There Was)


The Road to Pterosaurs:
Today, the long line of archosauromorphs has only two living representatives in crocodilian and bird species; all the rest are extinct. Diapsid archosaurs, as discussed in ‘Et Tunc Nulla Erat V’ and in a mainline evolving into the crocodilian groups in ‘Et Tunc Nulla Erat VI’, were also further evolving into other more familiar family groups...the pterosaurs, dinosaurs and birds. This was due to ambient environmental isolation and natural selection.

Archosauriformes were becoming isolated due to the breakup of Pangea causing genetic drift giving natural selection dominance to those species that were evolving an advantage to survive. At the end of the Permian and the beginning of the Mesozoic Era in the early Triassic Period, the Permian mass extinction laid the groundworks for newer evolved species to cope with changed ambient environments, filling the niches of older reptiles that couldn’t and therefore became extinct.

As a result of what all was going on with Earth, the Archosauria order split into two main lines. One was the Pseudosuchia (Phonetics: Sue-doe-soo-chia) clade that lead to the crocodilian line and its sister taxon clade, Avemetatarsalia (Phonetics: Ave-met-ah-tar-sal-e-ah) that eventually lead to pterosaurs, dinosaurs and birds. Avemetatarsalians are archosaurs that were more related to birds than to crocodiles and alligators. The name itself refers to ‘bird metatarsals’.


The archosaur pseudosuchian and avemetatarsalian taxa ancestry most likely arose from very distant cousins, the long necked protorosaurians of the Permian. As you read reptile evolution books, Protorosauria (Phonetics: Pro-toe-row-sar-ee-ah) is synonymous to Prolacertiformes and Prolacertilia.

The archosauromorph protorosaurs arose in the Late Permian becoming extinct during the beginnings of the Late Triassic 252 mya. Formed by elongated cervical vertebrae, they had rather long necks. The 2m/6.6ft long, Protorosaurus speneri (Phonetics: Pro-toe-row-sore-us spin-er-e), was terrestrial, fast and quick chasing after its most likely meals in insects. It may have also been omnivorous or even herbivorous as the coniferous plant in the genus, Ullmannia have been found in fossilized protorosaurus stomach contents and coprolites.

Another long necked protorosaurian was, Langobardisaurus, (Phonetics: Lan-go-bard-ee-sar-us). Living during the Late Triassic, 228-201 mya, this protorosaurus at 50cm/20in also had a long neck with even a longer tail to counterbalance. With the long tail, Langobardisaurus could rear up on its hind legs. It also had hollow limb bones, large orbits that supported excellent diurnal vision and with most fossils found along marine shorelines, most likely dieted on small crustaceans and small scaly fish as its dentition formula was used for grinding. It also took in an insect diet.

Langobardisaurus

From the archosauromorph line many clades arose with one leading to, Crocopoda (Phonetics: Croc-o-poe-duh). Crocopoda is a new listing set up by paleontologist, Martín D. Ezcurra in 2016. With a newly constructed data matrix, Ezcurra discovered that Aenigmastropheus (Phonetics: In-nig-mas-tro-phee-us) was indeed an archosauromorph, but was a sister taxon to archosauriforms, therefore were not in the direct line of Archosauriformes. To distinguish this, he enlisted all Archosauriformes archosaurimorphs under the clade, Crocopoda.

The archosaurian clade line eventually led to Archosauria producing the crocodilian line, Pseudosuchia and its sister taxon, Avemetatarsalia, the bird line, which includes pterosaurs and dinosaurs.     
      
Archosaurians are the crown group of true archosaurs. Crown groups as defined only include descendants of the last common ancestor of its living representatives. Showing up in the Permian some 250 mya, Archosaurus rossicus and Protorosaurus speneri were archosauriforms, although P. speneri only had some archosauriform traits in being an archosauromorph. If its line continued, it was trending towards an archosauriform nature.

Distinguishing characteristics of archosaurs trending towards avemetatarsalians were thecodont or socketed teeth, antorbital and mandibular fenestrae, which are openings in front of the eyes and in the lower jaw (mandible) and development of a fourth trochanter. Trochanters are bony protuberances by which muscles are attached to the upper part of the thigh bone. This gave archosaurs much stronger hind leg muscles heeding a more erect gait.

Avemetatarsalians first appear in the end of the Early Triassic around 249 mya. This is the same time wooded trees make a full recovery from the Permian/Triassic extinction. With the appearance of Avemetatarsalia, the earliest bird line group appears. The central biomechanical theme of this avemetatarsalian evolution is the functional decoupling of forelimb and hind limb function for bipedalism or powered flight. The ankle joint runs between the proximal and distal tarsals. This functional decoupling enabled the four limbs to evolve into different forms.


In further evolvement, Avemetatarsalia divided into two main subgroups; that being the sister taxa, Ornithodira (Phonetics: Or-neeth-o-deer-ah) and Aphanosauria (Phonetics: Ah-fan-o-sar-ee-ah). Aphanosaurs were four genus groups that were carnivorous, generally small with long necks while evolving and becoming extinct all during the Triassic 247-242 mya. In being quadrupedal, phylogenetically, aphanosaurs were the first and oldest yet known member of the avemetatarsalian clade.

Credit: David E. Fastovsky, David B. Weishampel

Where crurotarsan ankles had to accommodate differing types of angled movement, in eliminating the constant acute angle changes the ornithodiran mesotarsal ankle was evolutionary. Its axial-ankle transmitted the same single plane leg bone movements to the foot bones.

Scleromochlus taylori (Phonetics: Sclair-o-mo-klus tay-lori), at 180mm/7.1in was a small Late Triassic (228-235 mya) avemetatarsalian. Scleromochlus, meaning, ‘hard fulcrum’ in Greek may be the basal ancestor to pterosaurs. It had classic slender bird-like characters of a tibia that was longer than the femur and an appressed group of four elongate metatarsals. It also appears that most basal pterosaurs shared the same hind limb morphology as Scleromochlus

Although some paleontologists claim Scleromochlus was on its way to the pterosaur line as a basal ornithodiran, it wasn’t quite an ornithodiran (my opinion) due to possessing a more primitive ankle structure and short neck. The term, Ornithodira actually means ‘bird neck’. Leg section ratios of S. taylori show that the cursorial (running) bipedal animal had a definitive tendency towards saltatorial (hopping) locomotion as it preyed on insects. It quite possibly scavenged carcasses as well.

Pterosaurs as mentioned above are distantly related to protorosaurs. With longer hind limbs, protorosaurs had set the stage for bipedal locomotion with hollowed out bone limbs. Saltorial locomotion, or bipedal hopping as done by Scleromochlus could’ve given rise to pterosaur anatomical bipedal locomotion as pterosaurs had plantigrade hind limbs; an adaptation for saltitation. Scleromochlus meaning ‘hard fulcrum’ in Greek, may be a basal ancestor to pterosaurs.

Artist: Mark Witton  Scleromochlus

As a stem group, ornithodirans, sometimes called, Pan-Aves due to phylogenetic relationships to birds, gave rise to two sister taxa, Dinosauromorpha and Pterosauromorpha. Ornithodirans were the last common ancestors to pterosaurs and dinosaurs. Of course as nomenclated, dinosauromorphs gave rise to dinosaurs, while pterosauromorphs gave rise to the pterosaur line. In total, there are at least 13 characters uniting pterosaurs that aren’t found in combination or at all in dinosaurs.

To be clear pterosauromorphs and dinosauromorphs arose from ornithodirans, but from there, they evolved in separate ways. Both groups do share ornithodiran characteristics, but in total, there are at least thirteen characters that unite the pterosaurs that are not found in combination or at all in dinosaurs. In moving off into their own evolutionary histories, pterosaurs are not dinosaurs just as humans are not spider monkeys, even though we share a common ancestor.

In osteological (bone) features, in particular for the skull, ornithodirans experienced a rapid rise in postcranial skeletal pneumaticity (PSP). Skeletal pneumatization is the presence of air sacs within the skeleton. This is particularly evident in PSP ornithodiran derived fenestrae fossils, which is the modification of the postcranial skeleton by pneumatic diverticula of the respiratory system. It is widespread in saurischian dinosaurs including birds, non-avian theropods, sauropods and it is also present in pterosaurs. As well, throughout the phylogeny and anatomy of ornithodirans, pneumatic diverticula were widespread. Pneumatic trends gave rise to a lighter skeletal structure enhancing pterosaur flight.

Pterosaur Traits:
Unfortunately, there has yet been a basal ornithodiran fossil find that led to pterosaurs. But as the search continues, one day it will be found. This leads us to Pterosauromorpha (Phonetics: Tear-o-soar-o-mor-fah). This is an imposed superorder basal clade that led to and includes all the pterosaurs. As yet to be discovered, there are no primitive pterosauromorph proper fossil finds that led from transitional to anatomically factual pterosaurs. This is due in part that pterosaurs and most likely their ancestry osteology had bones that were at times paper thin and did not fossilize well during the Triassic Period. Also, many of the basal pterosaurs and their earlier relatives lived in regions of an environment that were not prone to preserving and fossilization.

With that said, however, there has been a recent discovery of a little creature nomenclated as, Faxinalipterus minima (Phonetics: Fax-in-al-ip-teh-rus min-ee-muh). It lived around 217.5 mya and was tiny at having no more than a 25cm/10in wingspan. Debate is still out on whether it was a most basal pterosaur, or the ancestral reptile that led to pterosaurs. Regardless, of whichever direction the debate concludes, it is tied into pterosaur lineage and the fact that it lived in inland forests, pterosaurs did not derive from coastal seashores as once thought.

Artist: Vitor Silva  Faxinalipterus

Under Pterosauromorpha, there are two suborders that represent an evolutionary grade time wise and anatomically; they are: Rhamphorhynchoidea (Phonetics: Ram-for-reen-coi-dee-ah) and Pterodactyloidea (Phonetics: Tear-o-dac-till-oid-e-ah). Rhamphorhynchoids, supporting seven families, were the earliest and most primitive of pterosaurs in possessing long tails, shorter wingspans, short metacarpals and had teeth. Pterodactyloids generally were more evolved with shorter tails, much longer wingspans, long metacarpals, while possessing in the later forms, toothless beaks and the absence of full bodied pycnofibers. The earliest pterodactyloid discovered so far with a wingspan of 1.4m/4.5ft was, Kryptodrakon progenitor. Krypto is Latin meaning ‘hidden’ while also in Latin, drakon is for ‘dragon’. Kryptodragon occurred 162.7 mya being a basal most pterodactyloid.

Artist: Román García Mora  Kryptodrakon

For a while, there was no in between representatives in the fossil record that bridged rhamphorhynchoids and pterodactyloids, but due to recent finds that has changed. While rhamphorhynchoid antorbital fenestrae and the nasal openings remained separate, pterodactyloids had them transposed together, collectively known as the nasoantorbital fenestra.

Anurognathidae (Phonetics: An-u-roe-nath-eh-dee) was a family of small pterosaurs that was a sister taxon to pterodactyloids. Although a sister to pterodactyloids, anurognathids still possessed enough of rhamphorhynchoid morphologies, such as separate antiorbital fenestrae and nasal cavities, short metacarpals and necks to be excluded from within the pterodactyloid group. There were four anurognathid genera.
Artist: Gabriel Lío  Allkauren

Most recent fossil finds of a well preserved new pterosaur braincase called, Allkaruen koi (Phonetics: All-kah-rue-in koi), along with the newer family wukongopterid finds still possessed rhamphorhynchoid primitive traits. But these are considered as transitional pterodactyloids in having a nasoantorbital fenestra.

In the above pterosaurs possession of both rhamphorhynchoid and pterodactyloid traits, demonstrates a classic example of ‘modular evolution’, where different body parts do not appear in systematic succession; they appeared in integral stages over time.

At the time pterosaurs, the first true vertebrate to conquer powered flight, were evolving, the super continent Pangaea during the Mesozoic Era was still in the process of breaking up, isolating pterosaur species from their basal ancestry. With new ambient environments coming into play through geological and climatic processes, as with the earlier archosaurs mentioned above, natural selection began developing earlier pterosaur species into newer ones with advantageous traits to fit niches vacated by older extinct forms. As a result, by the early Cretaceous, pterosaur species were represented worldwide in all types of environments.

Credit: BBC Ornithocheirus

Contrary to original beliefs, most pterosaurs were terrestrial as opposed to being neritic (coastal) or littoral (shoreline). However, Ornithocheirus simus (Phonetics: Or-nah-thock-care-us see-mus) quite possibly was pelagic flying across the Tethys Sea as its fossil remains have been found in strata from what is now Europe and South America.
Artist: Valter Fogato  Pterodaustro

Another misconception is that pterosaurs skimmed surface waters for fish. This is highly unlikely, where most likely, they picked fish off from the surface with their mouth. Even their hind claws, unlike talons of raptors were not adept in capturing and seizing prey from water surfaces. But in the genus, Pterodaustro, it strained food from waters with a combed mouth similar to baleen whale straining.

Various skeletal anatomies       

Most de facto pterosaur species had elongated fenestrae skulls in contrast to a shorter vertebral column. All pterosaurs had beaks made of keratin. In most toothed species, the beak at the tip of the jaws (maxilla) was restricted from teeth, where the teeth were more set in the jaw bones (premaxilla) toward the aft middle and back of the mouth. Keratinous beak tissue has been preserved in fossil finds.

Some pterosaurs experienced indeterminate growth as displayed in their skeletal structures, meaning they continued growing throughout their lives, where a few were determinate where growth stopped once into adulthood as pteranodon complete bone fusion has been recorded in finds.

Dimorphodon walking

Pterosaur tracks
All pterosaurs were quadrupedal walking on all fours and judging from preserved pterosaur footprint impressions, were quite efficient in their gait regardless of the limbs supporting winged membranes. Center of gravity though, was placed high giving an erect gait. So, a bipedal gait would’ve been more efficient in faster locomotion. Putting the long wing finger up and to the sides in keeping the wing out of the way, pterosaurs were plantigrade walking on the whole foot. This has been confirmed from pterosaur fossilized footprint impressions. Latter scavenging pterosaurs relied on terrestrial locomotion to locate food as much as by flying.

Artist: Julius Csotonyi  Pterosaur running 

In considering pterosaur bony crests, it was originally thought of as rare, but discoveries in the rhamphorynchoids, Pterorynchus (Phonetics: Tear-o-reen-cus) and Austriadactylus (Phonetics: Aus-tree-o-dac-till-us) proves that crests evolved much earlier than once believed in the more primitive pterosaurs. Some of the more evolved, Pteranodon (Phonetics: Tear-an-o-don) specimens supported crests while tapejarid species supported huge crests in relation to head size. Pterosaurs even supported a keratinous crest with no underlying bone. Keritin crests suggest they had color. Crests most likely were for mating purposes in warding off other males and attracting females; the bigger the crest...the better.
Artist: Mark Witton  Sordes

Some pterosaurs, especially the more primitive ones possessed pycnofibers, which were not hair or fur, but flexible hair-like filaments that were not attached as deep set like hair or fur follicles underneath the skin. Sordes, (Phonetics: (Sor-dess) and Jehholopterus (Phonetics: Jay-hole-opt-er-us) were two rhamphorhynchoids that indeed were fully covered from head to toe in pycnofibers. These two pterosaur fossils, among other finds, were found with pycnofiber pelts surrounding the body.

Other pterosaur species had longer pycnofibers on the back of the neck and throat than on other parts of the body, while some only had the neck covered. Pycnofibers as insulation allude to an endothermic (warm blooded) existence in pterosaurs. Most all other pterosaurs had actinofibrils internally throughout the wing membranes. These, as they first were, are not to be confused with pycnofibers. The actinofibril function was to strengthen the wings.

Wings folded down in to the sides then up from the enlarged digit when not in flight. The size of pterosaurs is normally measured by wingspan and not by body length. The reason being is that pterosaur wingspans were increasingly trending to be much larger than the body.

Nemicolopterus skeletal size
Artist: Lewis Smith  N. crypticus









Pterosaur statures ranged from sparrow size to a Cessna AA airplane. At 25cm/10in, the smallest pterosaur was Nemicolopterus crypticus (Phonetics: Knee-me-koh-lop-ter-us crip-tuh-cuss) living 120 mya in forested habitat as the limb digits were adapted for grabbing branches in an arboreal lifestyle. The longest pterosaur wingspan is not the more known, Quetzalcoatlus northropi (Phonetics: Kwet-zal-co-at-las nor-throe-pee), but, Hatzegopteryx thambema (Phonetics: Hat-zuh-gop-ter-ex tham-buh-mah) which had a wingspan of up to 12m/39ft. The fossil skull alone measures 3m/9.9ft;

Artist: Thomas Koivurinne  Quetzlcoatlus

In speaking of shape, one pterosaur, Pangupterus at 0.7m/2.3ft and with a long very slim beak looked like a hummingbird on steroids with teeth.

Artist Joschua Knüppe  Pangupterus



Like all modern day flying birds, pterosaurs had a keeled sternum. Earlier pterosaurs had tails for counterbalance, while later species lost the tail due to other characteristics, like longer wings that made them more maneuverable during flight.

One secret to pterosaur flight (and it is now understood that all pterosaurs could fly) was in the musculature of the arms. The front limbs were much stronger than their hind limbs. This is not to say their hind limbs weren’t adequate though, for all limbs were used for thrust as well in takeoff. The wings as verified through biochemical analysis were attached to all four limbs, for if the hind limbs did not support the membraned wing spread, the loading would cause the pteroid to fail.


Evidence of a lung-air sac system allowed precise controlled skeletal breathing with pump supports as a flow-through pulmonary ventilation system. This is analogous to that of birds. This relatively high efficiency of flow-through ventilation was one of the key developments in pterosaur evolution providing a respiratory and metabolic potential for active flapping flight and pterosaur colonization of the Late Triassic skies all the way to the end of the Creataceous.

Indeed, even the largest of pterosaurs flew. In earlier observations of the larger pterosaurs, scientists could not configure how a 10.7m/35ft plus animal could take off. This was proposing a conundrum of epic proportions. How could a large pterosaur, such as the azhdarchids take off? If they couldn’t fly, then why were their wings still evolving into much larger spans if they couldn’t be used for flight?

We’ve learned a lot since first studying pterosaur flight and it primarily has to do with power magnification. This is a trait in animal systems allowing a production of much higher power outputs than normal for short periods of time. From extant animals, we now know there is a predictable trend in anaerobic fiber composition as body size increases in flying animals. Today’s smaller animals that fly via continuous flapping carry more aerobic muscle than anaerobic muscle. So we know that small pterosaurs munching insects on the wing would probably carry mostly aerobic muscle having to continuously be flapping and maneuvering through environments full of obstacles such as trees.


Extant soaring animals, such as birds only flap for short bursts relying more on thermal air currents to stay afloat in the skies. Soaring forms of today, like the albatross, pack their muscles more with anaerobic fiber tissue creating a far greater output of energy for short bursts. In analyzing bird flights, where aerobic capacity tops out around 175 Watts/kg of muscle, fast twitch anaerobic fibers in birds put out 390 Watts/kg.

Artist: Julia Molna  Pterosaur terrestrial vaulting

Larger pterosaurs were mainly quad launchers in takeoffs in having all four feet planted on the surface. In takeoffs, would push and lift the hind limbs, then with the larger forelimbs used the anaerobic muscle tissue to gain an instant thrust in catapulting themselves from the ground or launching themselves from a water surface. Once in the air, a few flaps of the wing and they began riding the air currents in soaring fashion.
Artist: Mark Witton  Pterosaur aquatic launching

Forelimb musculature
In that pterosaur forelimbs were not uniaxial, the individual limb bones did not operate in a straight plane vertically or horizontally. Pterosaurs possessed a patagium (wing membrane attaching the forelimbs to the hind limbs), but did not have a uropatagium like bats that connected the hind limbs to the tail. Instead, pterosaurs had a cruropatagium on each side that connected the hind limbs leaving the tail free. In this fashion, the hind limb cruropatagia (plural for cruropatagium) were decoupled from the legs by being split in the middle giving the legs more freedom in locomotive movement. In flight, even though the cruropatagia were shallow membranes, the membranes provided lift during pterosaur flight.  
    
Pterosaurs reproduced in the laying of soft, permeable leathery eggs. Most of us feel that all pterosaurs nested on sea shoreline ledges because that is what was originally interpreted and reported. Due to some nicely preserved pterosaur eggs from China, it appears that burying their eggs in sand were more pars for the course. The eggs of Hamipterus tianhanensis (Phonetics: Ha-mip-ter-us tee-un-han-in-sis) were so well preserved that 3-D CAT scanning images were made of the contents which gave an artist a perfect subject to illustrate. The egg finds also prove that pterosaurs were social animals at least in nesting sites and rookeries.

Embryos
Artist's illustration











Whether pterosaurs tended to their young as in some instances of fossil finds, adults were with juveniles suggesting so; however the verdict is still out. From the egg finds, pterosaurs were pretty much fully developed to fend for themselves upon hatching and didn’t need parental care as is the case for other egg burying reptiles such as lizards and turtles. However, flight studies of hatchling pterosaurs conclude the wings and forelimb muscles were too weak for immediate flight, but could walk until the wings had time to function in flight.


Artist: Masato Hattori  A Caiuajara family?

In diet, pterosaurs ran the gambit in some being durophagovores, insectivores, piscivores, herbivores, carnivores, omnivores, filter feeders, scavengers and possible frugivores.

Credit:Atlantic Productions/ZOO EFX  

Artist: Andreas   Filter Feeders

There may have even been pterosaur cleaners acting on symbiotic mutualism in the relief of other cooperative vertebrates by feeding on ectoparasites and dead skin.

Artist: Mark Witton  Azhdarchids feeding off Kryptops

More and more in geographical ranges, we are finding out that pterosaurs overlapped globally with fewer species being endemic to simply one environment. Pterosaurs had spread the world over. Even Greenland was inhabited by the pterosaur eudimorphodontid, Arcticodactylus. Of course then, during the Late Triassic, Greenland as conjoined between North America and Europe, annualized average temperatures were more humid than cold at 26° C/79° F.

Artist: Joschua Knüppe  Arcticodactylus

Before we go to pterosaur species I’d like to note that, David Peters, an acclaimed paleontological illustrator and expert fossil osteologist, claims that pterosaurs were derived from basal archosauromorphs through a clade he coined as, ‘fenestrasaur’ due to all in sharing an antorbital fenestra. The majority of paleontologists rejects his ideas and gives solid reasons as to why. But, Peters is worth the time at giving a look at if at least in a skeptical mode. His website is the ‘The Pterosaur Heresies’.

To further muddle pterosaur evolution, if I may, I’d like to suggest, even interject a personal opinion concerning the pterosaur wing. All vertebrates, except for the basal tetrapods and certain modern amphibians have five digits. Even the two extant two-toed and three-toed sloth species both have three functional digits with digits ‘I’ and ‘V’ reduced to a singular metapodial. For the most part, from reptiles to mammals, extinct or extant, all have five digits on their four limbs made-up each of four phalanges (singular: phalanx). The one exception is pterosaurs possessing only four digits on their winged forelimbs with the pinky finger, digit ‘V’ totally removed. I dispute that; I contend that pterosaurs do indeed have five digits.

Current consensus among paleontologists is that pterosaurs lost their fifth digit which is recognized as the Roman numeral, ‘V’ digit in illustrations and articles. ‘I’ is the pollex (thumb), ‘II’ is the pointing finger, ‘III’ is the middle finger, ‘IV’ is the ring finger, while ‘V’ is the little finger (pinky).

Modern fossil scholars contend that the greatly enlarged digit that supports the pterosaur wing is digit ‘IV’, the ring finger. This makes sense, for most all reptiles, extant or extinct the ring finger digit is the longest. Because the basal pterosaur fossil record is sparse due to lightweight hollow bones not fossilizing well and no fossil finds have been recorded yet that even shows at least a vestigial digit, there isn’t even conjecture on what happened to the lost ‘V’ digit. For current thought, this also makes sense, since the smallest finger would logically be the one to atrophy into oblivion.  However, I say they have it all in reverse.

Please study the illustration below of a left wing of a pterosaur displayed from the ventral side. In the illustration, pointed out by the orange arrow, ‘pt’ stands for the pteroid, a bone that is unique only to pterosaurs. The pteroid supported the small wing membrane inside the arm. As it stands, it is explained that the pteroid was connected to a wrist bone.



Normally, evolution does not come up with new bones, it takes an existing one and rearranges its structure to accommodate a new function. An example of this is mammalian auditory ossicles commonly known as the middle ear bones. These three bones known as the malleus, incus and stapes (or the hammer, anvil and stirrup in common terms) evolved from the jaw bones of synapsid reptiles. The proof is evidenced from embryological averment, in that the mammalian ear bones originated from the reptilian articular and quadrate jaw bones.  

I’m contending that the pteroid is actually the vestigial remnant of ‘I’, the thumb, which is attached to a metacarpal (hand bone) supported by the trapezium (a wrist bone). The elongation from the thumb, as digit ‘I’ is actually an extension of the claw/nail forming from a vestigial thumb metacarpal stub that thickened into a keratinized sheath. The thumbnail is the thickest of nails to begin with. The pteroid on most pterosaur fossils is sword shaped, just like a claw grows.

This leaves the pinky finger, ‘V’ as the elongated digit supporting the whole of the wing. Through this contention, pterosaurs still possessed five digits as their ancestry did before them; it was just simply modified and rearranged for flight.

Now, since that’s out of the way, let’s move onto some pterosaur representatives.

Pterosaur Groupings:
In looking at the simple tree illustrated below, we see the rhamphorhynchoids in blue at the base and higher up in the tree limbs, later on the pterodactyloids in red evolve. The illustration lists them as clades, but essentially Dimorphodontidae, Anurognathidae, Campylognathididae, Rhamphorhynchidae, Ornithocheiroidea, Ctenochasmatoidea, Dsungaripteroidea and Azhdarchoidea are pterosaur families.


Please note that there is a major shift in the anatomy of pterosaurs as the pterodactyloids evolve from the rhamphorhynchoids. For example the loss of teeth in all of the azhdarchoids (H) or the low crest appearance in the dsungaripteroids (G). The proximity of the branches to each other determines how closely related to each other they are based on their most recent shared ancestor. For instance, the dsungaripteroids and azhdarchids share an ancestor at the point marked [*] and these two share an ancestor with the ctenoschmatids at point [+]. Similarly, all the three groups in the ornithocheirids share a common ancestor, and within them, Istiodactylus and Ornithocheirus are closer to each other than to Pteranodon.

Sixteen families that weren’t included in the illustration are, Eudimorphodontidae, Austriadraconidae, Raeticodactylidae, Wukongopteridae, Gallodactylidae, Germanodactylidae, Ornithocheiridae, Lonchodectidae, Chaoyangopteridae, Istiodactylidae, Anhangueridae, Thalassodromidae, Pteranodontidae, Tapejaridae, Boreopteridae and Nyctosauridae.

Rhamphorhynhcoids:

Rhamphorhynchoidea is the more primitive of the two suborders in Pterosauria.


Eudimorphodontidae (Phonetics : U-dee-morf-o-don-tee-day ) ~ Occurred during the Late Triassic 228-201 mya; Arboreal gliding reptiles are thought to be the ancestor; Thus far, are the earliest discovered group of derived pterosaurs; Contains three genera having one species in each genus, but the prevailing thought has reduced the genus, Eudimorphodon from originally three species down to one; Other eudimorphodontid species of the genus, Eudimorphodon have been reassigned;  E. cromptonellus is now the genus, Arcticodactylus and E. rosenfeldi, is now, Carniadactylus;  Another 
Artist: Fabio Pastori
eudimorphodontid species first listed under Eudimorphodon, is now recognized as Bergamodactylus wildi or as another species under Carniadactylus.  Eudimorphodont refers to having two different types of teeth; Are basal to more derived pterosaurs such as campylognathids; these diminutive to small primitive pterosaurs were from .30m/1ft-1m/3.3ft; Had short wings, ulnas and tibias; proximal limb segments, such as humerus, ulna, femur and tibia were of nearly equal length; the jaws supported multiple cusped teeth throughout the tooth row, while many also had fangs; Most likely dieted on insects, small fish and certain plants as dentition supported chewing; This group set the stage for many more pterosaur groups to come.



Austriadraconidae (Phonetics: Aus-tree-ah-draw-con-e-day ) ~ Occurred 208 mya in Late Triassic; Is holotypic containing only one genus and one species. Fossil find was over the region in what is now, Austria; Closest relatives are eudimorphodontids with Arcticodactylus having a short coracoid which is a paired bone making up a part of the shoulder assembly; Coronoid process in mandible is low while the shoulder blade is 62% longer than the coracoid; Wingspan is estimated at 70cm/27.6.



Raeticodactylidae (Phonetics: Ree-tic-o-dac-till-e-day ) ~ Occurred 205 mya at the end of the Triassic; As included in the superfamily, Eudimorphodontoidea are very close in relations to eudimorphodons; Contains one species from two different genera; Raetidactylus filisurensi and Caviramus schesaplanensis are now considered sister-species with Caviramus being a current accepted name; Wingspan for both species was 1.34m/4.4ft; Along with Austriadactylus, were the only Triassic pterosaurs to support a bony crest atop the head or snout; The upper jaw tips (premaxillae) held fang-like teeth, while the rest of the upper jaws (maxillae) supported up to five cusped teeth; Keeled lower jaw; Being rather small and with conical dentition, points to living in woodlands; Raeticodactylids were most likely swift flying insectivores.



Dimorphodontidae (Phonetics: Dye-morph-o-dawn-tee-day) ~ Occurred in Early Jurassic 195-182 mya, but if Peteinosaurus zambelli is a dimorphodon, as Mark Witton confesses, would drop dimorphodons back to 221 mya; Contains only two species thus far in, D. macronyx and D. weintraubi; Since no common ancestry to dimorphodontids as yet haven’t been discovered, some paleontologists prefer replacing

Artist: Mark Witton   2 dimorphodontids chased by Sarcosaurus

Dimorphodontidae with Dimorphodontia; Wingspans from 24cm/19.5in to 1.5m/4.9ft; The name implies two different teeth sizes; The upper and lower jaws contained 4-5 fang-like teeth at the tip, followed by numerous smaller ones; With short wingspans in proportion to body size and a small skull casing, dimorphodontids show primitive pterosaur characteristics; However, they were the largest pterosaurs that weren’t pterodactyls; Diet most likely varied as it was an inland as well as coastal animal with dentition and a weak musculature snapping jaw geared to biting into smaller animals such as lizards, sphenodonts and mammals of the day; Also, with fossils found near seashores, was most likely a supplemental piscivore.



Campylognathididae (Phonetics: Cam-pah-log-nath-id-eh-day) ~ Ocurred during the Early Jurassic 182 mya; Contains two genera with one species in, Campylognathoides and three in, Eudimorphodon; Wingspan ranges were from 1m/3.3ft to 1.8m/6ft; Were small coastal and inland pterosaurs; The caudal vertebra of the tail were lashed firm by tendons and most likely fitted the tail as a steering rudder during flight; With the long beak ending in a curving upward snout tip, long slender nares (nostrils) were present on each side; Strong musculature forelimbs prove this pterosaur was a strong flyer capable of a fast aerial lifestyle; Teeth were short and not laniary (adapted for tearing) but were for biting and piercing. With many fossils found in strata laid down along shorelines, was capable of grabbing fish on the surface via the mouth, but the dentition form was also ideal for grabbing and holding onto small terrestrial animals as well. 



Rhamphorhynchidae (Phonetics: Ram-for-rin-kee-eh-day) ~ The name is based on the group of Early Jurassic rhamphorhynhcoid pterosaurs appearing 180-148.5 mya; Contains ten species with eight listed below in the cladogram as two newer finds in Qinglongopterus guoi (Phonetics: Kwing-long-op-teh-ris gue-way) and Bellubrunnus rothgaengeri (Phonetics: Bel-lu-brun-nus roth-gan-jerr-ee) have just been nomenclated; Wingspans ranged from 30cm/11.9in to 2.5m/8.2ft; The primitive long



tails were stiffened by ligaments with most ending in the famous pterosaur diamond shaped vane; Jaws housed forward angled needle-like teeth except for the tip of the curved sharp beak that was toothless; Oceanic fish and cephalopods seem to have been the major diet as these animals’ remains have been found in rhamphorhynchid fossils where the gut would’ve been and in rhamphorhynchid coprolites; Fossilized impressions of wing membranes have also been found in their fossil remains.



Anurognathidae (Phonetics: An-u-roe-nath-eh-dee) ~ Species occurred in the Middle-Late Jurassic 164-145.5 (125) mya; Lived in what now is Europe, Asia and North America; A recent discovery of genus, Sinuiji (Phonetics: Sin-u-ah-gee) has been discovered in North Korea stretching the anurognathid timeline down to the Early 
Artist: Franz Anthony  Sinuili
Cretaceous; Sinuiji lived 125 mya; These primitive pterosaurs were diminutive ranging in wingspan from 35cm/13.8in to 80cm/32in; Although listed as a rhamphorhynchoid pterosaur, also possessed pterodactyloid characteristics such as a short tail with fused zygapophyses (two paired processes of vertebra interlocking with adjacent vertebra) and may later be introduced as a basal pterodactyloid; There is a 60 million year gap concern in their ancestry line as a rhamphorhynchoid; Contains three genera with a species each and three genera with four species in the subgroup, Batrachognathines; Had a much more rounded snout; Were very small woodland pterosaurs with large eye sockets, so probably were nocturnal and crepuscular active in hunting insects as dentition points to an insectivorous livelihood; Were mainly nocturnal chasing after flying insects or digging for them in the bark of trees with sharp long fore claws.  

Pterodactyloids:

Pterodactyloidea is the more derived of the two suborders in Pterosauria.



Wukongopteridae (Phonetics: Woo-kong-op-tur-eh-day) ~ Occurred in the Middle Jurassic/Late Jurassic border 164-153mya; Contains five genera with seven species; Were basal pterodactyloid pterosaurs possessing long vertebrae in the neck and a single nasoantorbital fenestra in front of the eyes; Are currently not listed as a true pterodactyloid, but as a transitional unranked form called monofenestrata; Wukonopterids demonstrate the bridge between the more primitive rhamphorhynchoids and the more derived pterodactyloids. Were small pterosaurs with wingspans ranging from 47.5cm/18in to 90cm/3ft; Possessed long tails with narrow wings and toothy jaws extended throughout the jawlines; All possessed crests; Had longer tails per body proportion than more derived pterodactyloids, which was enclosed by rod-like bony extensions of the zygapophyses; Living in temperate Jurassic forests of conifers, ginkgo and bennettites (extinct cycad trees), along with their bauplan, most likely were insectivores with the abilities of maneuvering through forests; Possessing sexual dimorphism, it appears that it was only the males who supported crests as remains of crested wukongopterids had narrower hips as opposed to remains in the same genus that didn’t have crests.



Dsungaripteroidea/Dsungaripteridae (Phonetics: Sun-guh-rip-tur-oi-dee-ah/Sun-guh-rip-tur-eh-day) ~ Occurred 155-112 mya during the Late Jurassic toward the ending of the Early Cretaceous; Contains nine genera with a species in each genus; Ranged in wingspan from 1.5m/4.9ft to 4m/13ft; Had small eye sockets placed high up in the skull; Starting in front of the nasal and ending behind the eye sockets, the snout had carried a high ridge; A bony projection also rose from back of the skull as a second crest; The limbs were well suited for terrestrial locomotion resisting compression or buckling; Most peculiar trait was the maxilla (upper jaw) which reached out and down then backwards giving an upwards curved snout; Snout tip was toothless with teeth in the back of the jaw forming a wide oval basis making them blunt; Teeth were only in the back of the jaws while in the upper back jaw, teeth were larger than those in the lower; This mouth arrangement made it ideal foraging for shellfish buried in mud; Acting much like a spade, the snout would dig underneath mud exposing a shellfish that could be cracked or bisected open by the blunt teeth exposing the soft bodied contents.



Gallodactylidae (Phonetics: Gal-lo-dac-till-ah-day) ~ Occurred in the Early Cretaceous 152-124.5 mya; Under this family, there are currently two genera containing one species in each; Is a sister taxon to ctenochasmatids; Were small pterosaurs with wingspans from 46cm/1.5ft to 135cm/4.5ft; Possessed parietal rounded crests on the rear portion of skull and jaws, but not near the end of snout like most other crested pterosaurs; Had a reduced nasal process placed on lateral side of skull; No gallodactylid had more than fifty teeth, beginning the trend of pterodactyloids’ loss of teeth and eventually toothless in the most derived; Most soared above the Jurassic shorelines and coast, much like sea gulls in search of fish on the surface; Some species supported jaw flanges to get at crabs and shellfish.       



Ctenochasmatoidea/Ctenochasmatidae (Phonetics: Ten-o-cazz-mah-toy-dee-ah/Ten-o-cazz-mah-tee-day) ~ Occurred 152-102 mya in the Late Jurassic and Early Cretaceous; Along with the gallodactylids and germanodactylids, the ctenochasmatids are all members of a group called the archaeopterodactloids, which are the more basal pterodactyloids; Contains five genera with a species in each except for Ctenochasma in having three species; Also contains two subfamilies; Wingspan range of family members were 50-60cm/20-24in to 2.5m/8.2ft; Most had straight jaws filled with needle form teeth; Teeth most likely formed spatula-like jaw profile extensions allowing for a larger surface area in catching prey; This, while also having wing proportions to modern shorebirds, possessing large hind webbed feet and long torsos alludes to the fact that their environmental niche was aquatic or at least semi aquatic shore animals; Ostensibly had a generalized carnivorous diet of fish, worms, frogs, salamanders or any other small shore animals they could scare up; With webbed hind feet and long torsos, it is most likely ctenochasmatids could swim.


Germanodactylidae (Phonetics: Ger-man-o-dac-till-ah-day) ~ Occurred in the Late Jurassic 151-148.5 mya; Contains two genera with a species representative in each genus; All species were small, possessing wingspans of around 1-1.1m/3.3-3.6ft; A bony ridge atop the long pointed beak supported a fleshy or soft keratinous tissue crest; The crest structure was an early form of pterodactyloid crests; Most were piscivorous, but the genus, Tendaguripterus (Phonetics: Ten-da-gu-rip-tuh-rus), from recent studies of its dentition may have preferred shellfish.


Ornithocheiroidea/Ornithocheiridae (Phonetics: Or-nah-thock-care-oid-de-ah/Or-nah-thock-care-eh-day ) ~ Occurred throughout the Cretaceous 145-66 mya; Contains four species proper with four more in the subfamily, Ornithocheirinae; Were the last of 
pterosaurs to possess teeth at the ending of Cretaceous; Most, except for Arthurdactylus were mid to larger pterosaurs possessing relatively larger wings and long wing fingers; Wingspans from 2.3m/7.5ft to 5.5m/18ft; Slippery food such as fish and squid made up the diet of coastal soaring ornithocheirids, while some species, such as Caulkicephalus has fossils in strata that was forested suggesting a freshwater diet; Soared long distances.


Lonchodectidae (Phonetics: Lawn-ko-deck-tuh-day) ~ Occurred in the Cretaceous 135-94 mya. Some scientists tend to ignore lonchodectids and assign them under other families; However, they are distinct enough to be included into a family of their own. Having ctenochasmatoid characterisitics, they also had limb proportions similar to azhdarchoids and ornithocheirid phylogenies, but had specialized dentitions unique unto their own. All lonchodectids, with one exception in Prejanopterus (Phonetics: Pre-jan-op-tuh-rus), possessed fully toothed straight jaws consisting of slender recurved conical teeth from the back to the tip of the jaws. Prejanopterus had a slightly dorsal curved jaw with twenty paired oval cross-sectioned teeth. The family contains six genera with one species in five of the genera, while the genus, Lonchodraco has three species. The genus, Lonchodectes contains five other dubious species where the fossil remains are scrappy and not complete enough to truly verify classification. When the mouth was shut, the teeth were loosely locked in zipper fashion. The humerus was molded in a straight plane more so than the contemporary pterosaurs. Most lonchodectids were terrestrial with a generalist diet, while Prejanopterus was more piscivorous.


Chaoyangopteridae: (Phonetics: Kay-ah-ee-yawng-o-tear-ah-day) Occurred in the mid portion of the Early Cretaceous 125-120 mya; Contains five genera with one species in each genus; Although it has currently been grouped with  dsungaripterids and thalassodromids under the clade, Neoazhdarchia, in reference to a basal azhdarchian line, there has not been a true understanding in its relationships to other pterosaur

Artist: Ali Sadekoff   Lacusovagus magnificens

groups; Chaoyangopterids had no crests; Was a smaller pterodactyloid with smaller necks and wingspans ranging from 1.1m/3.6ft to 1.8m/6.1ft; If, Lacusovagus (Phonetics: La-cu-so-va-gus)  becomes an accepted genus into the family, which it appears to be, its wingspan increases the family’s to 4.1m/13ft; Chaoyangopterids are one of the first pterosaur groups to be totally toothless; Diet hasn’t been fully determined, but is suspected of being piscivorous.


Istiodactylidae (Phonetics: Is-tee-o-dac-till-uh-day) ~ Occurred 125-120 mya in the Early Cretaceous; Contains five genera with six species; There are four genera with five species while with a fifth genus, Archaeoistiodactylus (Phonetics: Ar-kee-o-is-tee-o-dak-tyl-us) as questionable due to the poor fossilization posing difficult classification; Were medium sized pterosaurs with wingspans from 2.9m/9ft-5m/16ft; Though slender, the jaws and beak were rounded in duck fashion; Fossilized skeletal remains show this family of pterosaurs to be carnivorous scavengers; Razor-edged laterally compressed teeth; Teeth were fitted close together in front and were well suited for shearing flesh; The genus, Hongshanopterus (Phonetics: Hong-shan-op-teh-rus) was a basal istiodactylid having more teeth than any other istiodactylid, but teeth were small and retreating; Most had teeth only in the front portion of mouth; Their unusually broad muzzles allowed for sizeable portions of meat to be procured with each bite; Which suggests istiodactylids were the vultures of the Cretaceous, regularly feeding on large food items that had to be reduced into smaller pieces before swallowing; Istiodactylid retroarticular processes alludes to large jaw and throat muscles for tearing and pulling carrion; The elongate and wide occipital face enlarges the potential area for neck musculature anchorage which, like modern bird scavengers, 
Artist: Mark Witton
serves to assist in pulling and rending morsels of food from carcasses; Istiodactylid skull features were weak, such as the mandibular and rostra as compared to other carnivorous pterosaurs and as such, weren’t equipped to hunt down and tangle with prey; However, the skull was adept at controlling the forces sustained throughout the head during feeding on carrion. A feeding strategy comes from their short tooth rows, which indicates food was gripped in a proportionally small region of their jaws; Finally, the smaller eye orbits compared to other carnivore pterosaurs and strong arm musculature (evidenced by distally warped deltopectoral crests and deep sterna that enlarge the area for downstroke musculature attachment), show istiodactylids were well suited for soaring at hours on end with eyesight for locating dead meals instead of hiding or sprinting prey.


Artist: Nobu Tamura

Tapejaridae (Phonetics: Tape-jair-uh-day) ~ Occurred 125-85 mya in the Early-Late Cretaceous;  Contains eight genera and eleven species; Tapejarids are one of the closest relatives to azhdarchids;  Were widespread with fossils found in Brazil, Morroco, Hungary, Spain and China; Wingspans ranged from 2m/6.6ft to 5m/16.4ft; Tapejarids were wholly toothless; The dentaries (lower jaw bones that supported or

Artist : Cheung Chung  Huaxiapterus
could have held teeth) are anteriorly fused, forming a mandibular symphysis that accounts for approximately 50% of total mandibular length; This contrasts with the other known edentulous (toothless) pterosaur clades; Had elaborate circular crests covering  the entire top of the head; Are thought to have been omnivorous or even frugivorous manipulating the food item in its keratinous mouth and beak jaws to crack or crunch open in attempts to get at the contents and juices; During tapejarids’ appearance, the Cretaceous at the time was becoming much warmer with shallow seas 
Artist: Julius Csotonyi  Caiuajara with
extinct iguanian Gueragama
opening up; This created  isolated desert islands; Some islands had oases; Tapejarids lived on these islands; One was Caiuajara; (Phonetics: Kay-u-har-ah); Tapejarids were a pterosaur group that began displaying large crests; Many ideas have been put forth for large crest functions, such as acting as sails for aerial navigation, or species recognition; The best, I feel, was for thermoregulation; In hotter biomes, the crests released heat from the body cooling the animal down; Of course, the bigger the crest the male had, was in favor by the girls as a better success rate for offspring survival in hot climes.


Boreopteridae: (Phonetics: Bor-op-ter-eh-day ) ~ Occurred 124.6-120 mya in the Early Cretaceous; This family had has two genera with a species in each one. Another genus, Zhenyuanopterus, was initially considered to be a third genus, but current consensus concludes it is an adult form of the earlier genus find of Boreopterus, which is a known juvenile; Remains of both are too similar; Boreopterids are close in relations to ornithocherids; All of these pterosaurs had long thin wings; The heads supported long narrow jaws full of thin conical interlocking teeth and a crest atop the head; The teeth arrangements with the largest in front protruding outwards were freshwater piscivores snatching the slippery prey from the surface or plunging underwater to snare fish; Had the ability to swim, although they couldn’t float; May also have been opportunist carnivores.


Anhangueridae (Phonetics: Ahn-han-gair-ee-day) ~ Occurred 120-94 mya during the middle of the Cretaceous; Contains one genus with three species; Is a sister taxon to the ornithocheirid genus, Tropeognathus; Wingspan up to 4.5m/14.8ft; Was a southern pterosaur with fossil finds in South America and Australia; Contains one genus with three species; Possessed a rounded crest from the tip of its snout ending on the lower jaw; Had a long slender snout with sharp slender teeth pointing outwards in rosette fashion from tip of the snout; Were one of the last pterosaurs to have a full set of teeth; Evidently was a long distance pterosaur in soaring above waters subsisting perhaps exclusively on fish.

Thalassodromidae (Phonetics: Fah-lass-o-dro-meh-day) ~ Occurred in Early Cretaceous 108 mya; Currently is a small family containing only two genera with four species; Thalassodromids are a sister group to tapejarids and azhdarchids; With a common ancestor from the Dsungaripteroidea line; The name implies ‘sea runner’ for it was once thought  they were water skimmers; That misconception has been laid to rest, as they exercised terrestrial predation; Thalassodromids had an expansive crest supported by the frontals and parietals (skull bones) as it rises above the orbit (eye socket) and supratemporal fenestra (upper temporal skull hole); Crests were thin serving mating purposes and recognition functions; Had a shorter neck than other contemporary derived pterosaurs; Typical wingspans were from 4.5m/14.8ft to 5.3m/17.4ft; As a strong and swift flier, thalassodromids were predaceous on other smaller pterosaurs; On land and shorelines, with a toothless beak, but a long pointed one, were able to pierce to death larger animals.


Azhdarchoidea/ Azhdarchidae (Phonetics: Azzh-dark-oi-dee-ah/Azzh-dark-eh-day) ~ Occurred at the end of the Early Cretaceous to the end of the Late Cretaceous 108-66 mya; With that, azhdarchids were present on Earth longer than any other pterosaur group; Contains fourteen genera with a species in each; Five possible new finds may add to the list; Were the largest flying animal ever to soar Earth’s troposphere; Wingspans ranged from 3m/9.9ft in, Eurazhdarcho (Phonetics: Yur-azz-dar-coe) up to 12m/39.4ft in, Hatzegopteryx (Phonetics: Hat-zeh-gop-teh-rix); It’s been calculated by paleontologist, Mark Witton and others that azhdarchids had an averaged potential of anaerobic power magnification energy for short bursts before flight muscles tired; This suggests that these animals could go from a standing start to a few kilometers away in less than two minutes since calculations prove in short bursts, azhdarchids could reach speeds of 173kph/107.5mph; Azhdarchids have very peculiar biomechanics when it comes to neck vertebra; Applied allometric calculations of azhdarchid neck lengths show that they are neck and neck, so to speak with protorosaur, Tanystropheus at ~ 3m/9.9ft for the longest animal neck; Azhdarchid necks however were very limited in range mobility at the mid-series neck column, with most of the mobility limited to neck extremities; With this in mind, may I suggest that azdarchids held the neck in sinusoidal fashion a bit like in S-shape the greater blue heron does today. These pterosaur giants indeed did eat any sized dinosaur they could swallow.


Pteranodontidae (Phonetics: Tuh-ran-o-dont-ah-day) ~ Occurred 88-66 mya during the Late Cretaceous; Contains a large number of members even though it has been reduced; Reductions stem from the genus, Dawndraco proving to be a juvenile specimen of Pteranodon longiceps and removal of genera into other families. The two current genera, Pteranodon and Geosternbergia have eight species; Pteranodons are what most folk

envision pterosaurs to be as they were one of the first pterosaurs found and their fossil discoveries are in abundance; Possessed an upturned toothless beak; The upper jaw was longer than the lower; The most distinctive characteristic of pteranodontids was the cranial crest consisting of skull bones (frontals) projecting upward and backward from the skull ending in a point; Pteranodons showed sexual dimorphism with average male wingspans at 5.6m/18ft and females at 3.8m/12ft; Pteranodontids flew over the seas much like an albatross in utilizing dynamic soaring as well as catching uprising air currents created in between waves;

Had a high aspect ratio (wingspan to chord length) of 9:1 compared to the albatross of 8:1; Were most likely fully piscivorous, but may have also included other aquatic invertebrates into their diets. Many Pteranodon fossils show remains of fish in their guts; Fished most likely from wading/swimming rather than flying over water’s surface and plucking by mouth; Were adept at staying afloat and as built, could easily launch from water to get airborne; Pteranodontids showed sexual dimorphism and differing periods of growth rates, in particular in crest and beak sizes; The comparison pteranodontid head chart, illustrates this.


Nyctosauridae (Phonetics: Nick-toe-sore-uh-day) ~ Occurred 85-84.5 mya at the end of the Cretaceous; With one genus there were four species; Fossil remains have only been found in Kansas in the Niobrara Chalk Formation that was deposited 87-66 mya; Wingspans ranged from 1.9m/6.2ft to 5m/16ft; The heads supported a long ‘L’ shaped crest; Some paleontologists feel the crest supported flesh, but most feel now that it was in life as it was preserved in fossilization; An unusual trait is that there were no claws on the forelimbs suggesting more of a continual soaring lifestyle; Practiced dynamic soaring, flying into a trough formed by two waves then into the lee of a passing wave; Lees result in stronger air pressure as waves progress; This pressure resulted in air moving faster over wings increasing lift; In wheeling, turning around sharply back towards the trough, a back wind further increased speed; Most likely was wholly piscivorous flying over the once then, Western Interior Seaway; Nyctosaurid fossils are only found in the seaway’s formations.          

There may have been a family or two of pterosaurs I missed, if so, may ya be so ever kind as to forgive me, but due to further research studies and new fossil findings, pterosaur phylogeny and nomenclature are rapidly changing.

Pterosaur Species:



Credit: Vaderxl



Species: Eudimorphodon ranzii
Phonetics: U-dee-morf-o-don = ran-zee-eye
Family: Eudimorphodontidae
Wingspan: 1m/3.3ft
Diet: Piscivorous
Timeline: Late Triassic 210-203 mya

Description: Eudimorphodon (true dimorphic tooth); The species name, ranzii, honors, Professor Silvio Ranzi; Fossil finds are from northern Italy; The name implies two different dentition forms; All 110 teeth were small packed into 6cm/2.4in jaws, but had larger fang-like teeth at tip of beak for snaring and a few larger interspersed fangs; Mostly had much smaller whale-like heterodont back teeth that were cusped; Skull was triangular and long; The beak’s shape was birdlike; Bony tail ending in a vane was as long as the body; With a large head, short neck and relatively short hand bones, this basal pterosaur’s bauplan (body plan) most likely exhibited morphological features similar to pterosaur immediate ancestry.


Bio Specs: Discovered as fossil impressions, the diamond-shaped flap at the end of tail may have served as a rudder for steering and balance during flight; Fossils of adults and juveniles have been found; Three pairs of large fenestrae in the skull reduced weight; Is listed as a freshwater piscivore due to some fossil finds having included fish and fish parts such as scales in the gut area of the Eudimorphodon fossil; One Eudimorphodon fossil showed  remains of the fish, Parapholidophorus which was half the size of the pterosaur itself; The front teeth were ideal for grabbing and holding onto fish then crushing them with the back teeth; However with different dentition, surely foraged for other smaller animals that frequented shores, or even scavenged from larger carcasses just as shore birds do today;  In capturing fish near surface, had to have good eyesight to view just below water surface; Teeth from fossils also showed a lot of wear suggesting a harder diet like shellfish; This pterosaur with strong muscular arm muscles could easily propel from water into flight.


Artist: Rae-elic
Species: Austriadraco dallavecchiai
Phonetics: Auss-tree-ah = doll-la-vec-key-eye
Family: Austriadraconidae
Wingspan: 70cm/27.6in
Diet: Carnivorous/Insectivorous
Timeline: Late Triassic 208 mya

Description: Austriadraco (Austria dragon); Species name honors paleontologist, Fabio Marco Dalla Vecchia; Fossil find is from Austria’s Tyrol state on Reither Spitze Mountain 1600m/5,249.3ft up in elevation; Exhibited autapomorphic traits (distinctive features found only in one taxon) of bone branching; The frontal skull bone had a short branch; The jugal skull bone (found in reptiles) had short branches leading to the maxilla and nasal bone with a long narrow branch leading upwards toward the postorbital bone; The shoulder blade was at 62%, much longer than the shoulder coracoids; Austriadraco is one of the very few pterosaur finds from the country, Austria.     


Bio Specs: Is a small basal pterosaur but was adept in swift maneuverability during flight; Dentition suggests a carnivorous and/or insectivorous diet consisting of small vertebrates and large insects; Was found in the stratigraphical Norian Seefeld Formation, where once supported forests of conifer trees interspersed with cycads and extinct lycophytes, which were similar to ferns; So this early period pterosaur was wholly terrestrial.


Artist: Andrey Atuchin 
Species: Caviramus schesaplanensis
Phonetics: Kah-veer-ah-mus = she-saw-plah-nin-sis
Family: Raeticodactylidae
Wingspan: 1.35m/4.4ft
Diet: Piscivorous
Timeline: Late Triassic 205 mya

Description: Caviramus (hollow branch); The species name refers to Mount Schesaplana; Fossil finds are from Switzerland; One fossil entailed the limbs, wing phalanges, a portion of the disarticulated skeleton and head, while the other entailed the jaws and teeth; As a basal pterosaur, possessed probably more derived autapomorphies than any other pterosaur; The jaw was light and hollow; The humerus is thinner than that seen in other Triassic pterosaurs; The unusual femur with a caput femoris (femur head) is perpendicular to the shaft; Teeth of the premaxilla are monocuspid, large and fang-like exhibiting strongly bowed enamel wrinkles on the lingual side, whereas the enamel is smooth on the labial side; Numerous smaller teeth of the maxilla show three, four and five cusps; Some scientists, in not yet recognizing the family, Raeticodactylidae, still list, C. schesaplanensis under, Eudimorphodontidae; However, with unique differences it deserved its own family.   


Bio Specs: Discovered in marine sediment and along with dentition particulars most likely was piscivorous flying over the waterways along shorelines and scooping up small fish from the surface. Based on its long limbs, however it could’ve been a terrestrial forager seeking out small animals and insects; The rear multi cusped teeth were capable of mastification; Even though the jaws were hollow, jaw musculature gave a strong bite and was capable of biting through invertebrate exoskeletons or fish scales; Was one of the first pterosaurs to support a keratinous crest that rose abruptly from the front of the snout well above the head; Having the same fibrous textures as later crested pterosaurs that had softer tissue coverings, Caviramus’ small crest may have been endowed with a flesh covering.


Artist: Sasha Kozacenko
Species: Dimorphodon macronyx
Phonetics: Dye-morph-o-dawn = muh-krah-nix
Family: Dimorphodontidae
Wingspan: 1.5m/4.9ft
Diet: Insectivorous/Carnivorous
Timeline: Early Jurassic 195-190 mya

Description: Dimorphodon (two form tooth); Species name, macronyx stands for ‘big claw’; Fossil remains are some of the best of early pterosaurs exhibiting three dimensional qualities; In having light hollow bones, as in most pterosaur fossils the heads are compressed with skeletal remains as disarticulated due to strata stress movement over the eons; Were plesiomorphic as their evolutionary trait or character state is homologous within their particular taxon, but is not unique to pterosaur members and therefore cannot be used as a diagnostic character for the group, such as in having wings or legs; In its flight finger, the phalanx is only slightly longer than its lower arm; The teeth were larger in the front and smaller in the back; Dentition stood erect toward each other rather than flaring outwards; Consisting of thirty vertebrae, the tail was long; The whole of the bulky head was bony; The large skull fenestrae, to reduce weight, was separated from each other by thin bony partitions to add strength; The neck was short, but with very strong musculature and flexible vertebrae; Possessed large trenchant claws with powerful extensor muscles and strong arm musculature; Every claw was equipped with a neighboring sesamoid (bony nodule developed in a tendon where passing over an angular structure, typically in the hands and feet, or a kneecap).


Bio Specs: Primarily known from marine sediments living along shorelines and island environments of what is now Europe, although it did not feed on marine animals; The other dimorphodon, D. weintraubi lived in less aquatic-based environments, having been found with many types of terrestrial animals such as sphenodonts and dinosaurs; The beak is often compared to puffins, but physical build is the only sharing characteristic, as in function, Dimorphodon could not manipulate beak usage for diving into water while capturing small fish or small crustaceans; Instead, the toothed beak was used for capturing large insects and small vertebrates; This pterosaur’s beak was bony where the puffin’s is mainly made up of soft tissue; Dimorphodon morphology and sturdy osteology steered away from earlier pterosaurs sacrificing gracile flight and maneuverability for terrestrial strength in walking on land.


Artist: Chris Mannaghetti
Species: Campylognathoides zitteli
Phonetics: Cam-py-log-nath-oy-des = zit-tuh-lie
Family: Campylognathididae
Wingspan: 1.8m/6ft
Diet: General Carnivore
Timeline: Early Jurassic 182 mya

Description: Camplyognathoides (curved jaw); Species name refers to German paleontologist, Alfred von Zittel; Fossilized C. zitteli specimens, found in the Posidonia Shale, a marine formation preserving a shallow sea environment in what is now Germany; Although eudimorphodontids were more basal, Campylognathoides was a close relative with similarities in skull, sternum and humerus forms; The skull was generally elongated, high and flat but the snout it supported was short; The cranial extremity had a low and short cristopina (sternum attached forward facing ridge) that perhaps supported a little crest just above the eyes; Large orbitals (eye sockets) were set low in the skull; The teeth were conical and recurved but had a broad base with the point beveled off from the inside forming a sharp and strong cutting surface; Maxillaries (upper jaw bones) had four widely spaced teeth, while in the premaxilla (upper jaw tip of snout bones) gradually increased in size from front to back; Mandibles (lower jaw bones) had 16-19 smaller teeth with a fourth pair at tip of snout being largest; Had six short vertebrae in the tail base followed by elongate caudal vertebrae situated behind the base that were stiffened by very long tendon extensions; The pelvis was unique in that the hip socket forming an upward lateral position, prevented the pterosaur from being able to orient its legs erect.         


Bio Specs: Although fossil remains were found along a shoreline environment along with the piscivorous rhamphorhynchid, Dorygnathus, C. zitteli was more likely a generalist feeder of small vertebrates, invertebrates and small fish; Its short snout would not have afforded expertise in reliance on plucking fish out of water as its sole diet; Teeth were excellent for piercing, biting and chewing; The large orbitals supported eyes for excellent vision alluding to the fact that this pterosaur was nocturnal; The relatively long stiffened tail and short hind limbs would have accentuated major balance control during flights in maneuvering quick turns; A specific species name can be used for any animal, but a genus cannot; Originally named, Campylognathus, it was later realized that name had earlier been used for an African hemipteran insect, thus the reason for the current name, Campylognathoides.


Artist: Mark Witton
Species: Rhamphorhynchus muensteri
Phonetics: Ram-foe-rink-us = mu-in-stare-ee
Family: Rhamphorhynchidae
Wingspan: 1.8m/5.9ft
Diet: Piscivorous/Insectivorous
Timeline: Late Jurassic 150.8-148.5 mya

Description: Rhamphorhynchus (beak snout); The species name, muensteri named after fossil collector, Georg Munster; Fossil remains have been found in England, Tanzania, and Spain with the best preserved specimens coming from the Solnhofen limestone of Bavaria, Germany; Fossil finds have not only produced complete skeletal remains, but also wing impressions, other soft tissues, diets with gut contents, sexual dimorphism and venation at end of tail; The vane was lancet shaped skin; CAT scans of Rhamphorhynchus skulls have allowed for reconstruction of the inner ear;  Reveals that unlike other pterosaurs, Rhamphorhynchus typically flew with its head horizontally level as parallel to ground; The skull lacked any crests; The osseous labyrinth (bony part of internal ear) was filled with the fluid, perilymph; As oriented relative to the long axis of the skull, position of the labyrinth suggests a horizontal head posture; Enlarged semicircular canals of the skull were concordant to the orbitals; This reflects a highly refined organ of equilibrium, suggesting aerial predation as visually based; Enormous cerebellar floccular lobes suggests neural integration of extensive sensory information from the wing, further enhancing eye and neck based reflex mechanisms for stabilizing gaze; Studies of the scleral rings around orbitals where the eye was socketed, indicates a nocturnal lifestyle; Sharp conical teeth of Rhamphorhynchus intermeshed outside the jawline when the jaw was closed; There were no teeth at the tip of the beak.

Rhamphorhynchus vs. the fish, Aspidorhynchus 


Bio Specs: Fossil remains of baby R. muensteri hatchlings had wingspans of 30cm/11.8in; Fossils of juveniles indicate a much shorter snout with developed large eyes; Finding 1-yr-old and 2-yr-old juvenile flapling fossils, growth rates were determined to be 130% to 173%, a bit faster than the extant American alligator; Rhamphorhynchus fossils helped determine that this pterosaur wasn’t just an aerial predator, but also waded near shorelines foraging for food; Having hatchet-shaped deltopectoral crests, a short torso with short legs, shaped deltopectoral (anterior shoulder bone) crests and a short torso with short legs are all features associated with water based swimming and launching in pterosaurs; Teeth arrangement is suggestive of a piscivorous diet, however they were also ideal for capturing and holding onto smaller vertebrates such as amphibians; Smaller juveniles most likely remained terrestrial feeding on insects and other arthropods; Indeed, sometimes this pterosaur wound up as prey.

Artist: Josh Cotton

Species: Mesadactylus ornithosphyos
Phonetics: Me-sah-dak-tyl-us = or-nuh-thus-fee-os
Family: Anurognathidae
Wingspan: 70cm/28in
Diet: Insectivorous
Timeline: Late Jurassic 152 mya

Description: Mesadactylus (mesa finger); Species name, ornithosphyos derived from Greek standing for, ‘bird lower back’ in reference to the bird-like hip vertebrae; Found in the Upper Jurassic Morrison Formation of Colorado; Taphonomy (process of fossilization) of Mesadactylus remains’ site is composed of continental offshore coarse deposits rather than near shoreline sediments; However, the body could have been washed out to sea; Pycnofibers covered the whole of the body and head; CT-scans of cervical vertebrae reveal a complicated internal pneumatic system that can be compared to the avian system; Dentition was composed of rows of very small conical teeth; The skull had large orbitals with rounded snout and rounded jaw bones forming a wide mouth with nostrils placed at the front of snout; In the occipital region of the braincase, the occipital condyle and foramen magnum were oriented ventrally as in pterodactyloids; The parietal consisted of very thin bones that formed a short sagittal crest anterior to the supraoccipital, the exoccipital, the opisthotic and the basioccipital; The seven sacral vertebrae of the synsacrum (skeletal structure characteristic to birds and dinosaurs, in which the sacrum is extended by incorporation of additional fused or partially fused caudal or lumbar vertebrae) exhibited complete fusion of the spinae into a supraneural blade much like birds; The rest of the vertebrae were free; The tail was very short.          

Bio specs: Akin to bats in physical appearance and in nocturnal flight would be swift and acrobatic much like a bat; Anurognathids were very small and delicate pterosaurs, Mesadactylus was no exception; Covered with pycnofibers made it appear it had mammalian fur; This little creature was a woodland pterosaur and hunted insects by night according to its dentition and large eyes; To a degree, the eyes pointed forwards to suit more of a binocular vision flying through forests of tree limbs; With its peculiarly large forelimb claws, it may have also rooted out insects from underneath the bark of trees; Mesadactylus was the largest of anurognathids.

I am partial to these little anurognathids; they’re hands down my favorite petrosaur. So included below, are some more drawings of these cute little batty petrosaurs.


Artist: Andrey Atuchin
Anurognathus ammoni


Artist: Joschua Knüppe
Batrachognathus









Artist: Matt Mart
Dendrorhynchoides
Credit: Xiaolin Wang
Jeholopterus













Artist: Mark Witton

Species: Cuspicephalus scarfi
Phonetics: Cus-pis-sef-ah-luss = scar-fee
Family: Wukongopteridae
Wingspan: 1.2m/3.9ft
Diet: Piscivorous/Carnivorous?  
Timeline: Late Jurassic 150.8mya

Description: Cuspicephalus (pointed snout); Species name, scarfi honors cartoonist, Gerald Scarfe, who’s characters are drawn with outlandish long pointy noses; Fossils found in Kimmeridge Clay Formation of Dorset, England that preserved a marine environment; In reference to ontogeny (origination, development and maturity of an organism), the unfused atlas and axis suggests that these bones never fused, a common feature within other non-pterodactyloids, but type of triangular shaped head, a single long nasoantorbital fenestra and longer neck vertebrae, were pterodactyloid traits; Given a rostral index of 5.4, per body proportion the head was larger than any other pterosaur; On the anterior part of premaxilla, the crest is limited to dorsal margin of its skull; Crest remains made up of fibrous bone, Possessed small conical pointed teeth; Tail ended in a skin covered vane known as a vexillia;

Bio Specs: Although dentition was small, teeth were largest in front on the premaxillae declining in size further back; Teeth were housed in a much longer skull than its related Chinese wukongopterids; It was also larger than it China relatives; This is the clue that Cuspicephalus was a piscivore in snatching fish, although the larger front teeth as well, could have acted as a strain, trapping small fish and invertebrates as spoonbills today do; Even though fossils are found in marine sediment, Cuspicephalus’ small build would’ve relegated him to the edge of the seashore, so it either waded in calm waters along the shore or chased after small animals on land.     

Artist: Oliver Demuth

Species: Banguela oberlii
Phonetics: Ban-gway-lah = o-bare-lee
Family: Dsungaripteridae
Wingspan: ~ 4m/13.1ft
Diet: Carnivore?/ Durophagovorous (eats shellfish)
Timeline: Cretaceous 112 mya

Description: Banguela (toothless one); Species name, oberlii honors the Swiss fossil collector, Urs Oberli; As in all dsungaripterids, B. oberlii had an upturned beak, but in addition, was the only dsungaripterid that was toothless; However, teeth size was reduced and relegated to the back of the mouth in all other dsungariterids; This indicates that pterosaurs becoming toothless was independent in families as B. oberlii was only distantly related to other toothless pterosaur families; It possessed a fibrocartiliaginous fusion (symphysis) of the two lower bone jaws; Dsungaripterids had some of the most specialized teeth of all sauropsids, from parareptilians to birds, so Banguela’s toothlessness probably indicated some degree of divergent specialization.

Bio Specs: With upturned beaks, dsungaripterids most likely were durophagovore specialists combing beach shorelines digging through mud with their spade-like beaks to get at buried shellfish, then crush the shells with their back teeth; With its toothless beak, B. oberlii took this specialization to the extreme, becoming totally diet dependent on the soft bodied parts of shellfish; Being the largest and most derived dsungaripterid, B. oberlii, without teeth most likely maneuvered the shell with its larger and hardened beak bisecting it to get at the soft body; Perhaps eating any other small soft bodied animal that lived in or near the shoreline. Combing the beach shores it would’ve been adept in walking.

Artist: Chris Masnaghetti

Species: Cycnorhamphus suevicus   
Phonetics: Sic-no-ram-fus = sue-vee-cuss
Family: Gallodactylidae
Wingspan: 1.35m/4.4ft
Diet: Filter Feeder
Timeline: Late Jurassic 152 mya

Description: Cycnorhamphus (swan beak); Species name, suevicus honors the Suevi Germanic peoples who fought against the Roman invasion, with ‘cus’ as a Latin rooted masculine suffix; Fossil remains found in the Solnhofen limestone beds of the German state, Bavaria, which during the Jurassic was the edge of the Tethys Sea; Cycnorhamphus formed a monophyletic group with Pterodactylus and Germanodactylus; Appears to have gone extinct near the Jurassic-Cretaceous boundary; Cycnorhamphus had a very unusual jaw anatomy; Had peg-like teeth at the jaw tips, but blunter and stouter in older individuals; Jaws were curved behind dentition forming angled arc openings away from the biting surface; Jaw curvatures most likely served to hold shelled invertebrates to either crush or bisect them, much like openbill storks of today; The jaws were also shorter than other gallodactylid members; Age development is obvious as juveniles did not possess the full development of the specialized jaws; Young juvenile jaws were straight; A rounded crest rose up from the back of the skull onto two-thirds of the top beak in male adults; The length of the humerus and ulna were ~ 80% less than the length of the femur and tibia.         

Bio Specs: There is fossil evidence that C. suevicus experienced sexual dimorphism with the males being bigger and supporting a crest; As juveniles matured into adulthood, only then did they possess adult morphologies, as the jaws grew more curved in older aged fossil finds; most likely dieted on hard shelled invertebrates such as mollusks with the teeth arrangement more than capable of crushing or bisecting shells. Being such a specialized aquatic feeder and sediment sifter, they must’ve flocked together much like flamingos do today.

Artist: Dinoraul
   
Species: Pterodaustro guinazui
Phonetics: Teh-roe-daws-trow = gee-naw-zoo-ee
Family: Ctenochasmatidae
Wingspan: 2.5m/8.2ft
Diet: Filter Feeder
Timeline: Early Cretaceous 105 mya

Description: Pterodaustro (southern wing); Species name, guinazui honors Argentine paleontologist, Román Guiñazú; Fossil remains found in the laminated shale, Lagarcito Formation of San Luis Province of Patagonia, Argentina and the Santa Ana Formation in Chile; Remarkably long, slender and upward curving beak comprised 85% of cranial (skull) length; Skull roof of the braincase was subtriangular shaped with posteroventral (situated posteriorly and ventrally) oriented parietals, a low nuchal crest and ossified ethmoidal elements and interorbital septum; Some fossils are so detailed that scientists were able to identify foramina for cranial nerves; Vascular foramina identified are the caudal middle cerebral vein, the dorsal head vein, the internal carotid artery; and the columellar recess; The mandibles (lower jaws) had ~ 1,000 long, slender needlelike teeth that were packed closely together; The maxillae (upper jaws) in contrast had blunt short teeth; The entire premaxilla (tip of snout) formed the entire dorsal portion of snout as it nearly approached the rostral margin of the orbital; With no suture the two premaxilla are fused. Possessed a uniquely long tail for a pterodactyloid with 22 caudal vertebrae, which was six more than found in other group members;       

Bio Specs:  Lagarcito Formation of Argentina was once an inland, shallow alluvial lake; Abundant Pterodaustro fossil remains are in laminated claystones of a facies interpreted as deposits formed in offshore areas of lakes in the laminated claystones; Pterodaustro was not a true filter feeder with its mouth open while swimming to trap food; While wading or swimming, it would take in a scoop of water, close the mouth where the top beak sat inside the lower, squeezing the water out through the bristled needle-like lower teeth acting as a strainer, trapping small crustaceans, plankton and other small aquatic animals. Once trapped, food was crushed with the upper teeth then swallowed. Most likely a major food source was brine shrimp; Brine shrimp dine on Spirulina, an alga that produces carotenoids; This is what currently turns pink flamingoes pink; It is postulated that Pterodaustro, after utilizing the shrimp as a main food source could have also turned it’s pycnofibers or skin pink; Pterodaustro fossils have been found in abundance and throughout each life stage from embryos still encased in the eggshell to matured adults; Developmental growth showed juveniles growing to 53% of adult height within their first two years, but slowed down in reaching full adulthood in taking another four years; Once adulthood was obtained they experienced determined growth rates and stopped growing. With splayed feet and short legs, launching for flight would have been very difficult for a Pterodaustro, so most likely took-off as geese and ducks do by running the surface while flapping their wings.
Artist: Fabrizzio De Rossi

Species: Tendaguripterus recki
Phonetics: Ten-da-gu-rip-teh-rus = reh-key
Family: Germanodactylidae
Wingspan: 1m/3.3ft
Diet: Piscivore?/ Durophagovorous?  
Timeline: Late Jurassic 152.1-152 mya

Description: Tendaguripterus (Tendaguru wing); The fossil remains were named after the Tanzanian rock bed it was found in, the Tendaguru Formation; Species name, recki honors the collector of this pterosaur, German paleontologist and volcanologist, Hans Reck; As far as proper nomenclature goes, respected Brazilian paleontologist, Alexander Keelner feels that Tendaguripterus anatomy elements are only superficial in relation to other germanodactylids and insists it needs to be moved into a family of its own, naming it, Tendaguripteridae; So far as it stands today, due to lack of other more viable fossil finds, consensus still lists Tendaguripterus as a genus under, Germanodactylidae; Closest relations are with dsungaripterids; Teeth were small, but became progressively larger further back in the mouth and were raked backwards in position;  Known as a ‘region senfyseal’, both mandible halves fused into one element; The humeri possess the typical pterosaur saddle-shaped proximal articular head; Of unknown function, there is an elongated concavity on the medial side, close to the distal margin of the crest; The ulnar crest is blunt and highly concave with an elongated ridge on the medial side of crest running from the distal to the proximal edge; Scientists feel this was likely an attachment of a flight muscle making the crest deltopectoral; the deltopectoral crest length was measured at 5.95mm/0.23in.          

Bio Specs: The fossil remains were found in laid down lagoonal sediment; Judging by its dsungariptid relations, the teeth arrangement and where the fossil remains came from, Tendaguripterus most likely was a durophagovore snatching freshwater shellfish and crustaceans along shorelines and banks, piercing them with the sharp teeth then consuming the soft body parts; It also could have caught small fish along the edges of freshwater with the backward growing teeth keeping the slippery prey from escaping; Although is general in pterosaur morphology, Tendaguripterus was a rare Jurassic Gondwanan find, proving that pterosaurs had conquered the Late Jurassic southern hemisphere as well.
Artist: Julio Lacerda

Species: Caulkicephalus trimicrodon
Phonetics: Kawl-key-sef-ah-luss = try-my-crow-don
Family: Ornithocheiridae
Wingspan: 5m/16.4ft
Diet: Piscivorous
Timeline: Early Cretaceous 127.5 mya

Description: Caulkicephalus (caulkhead); The genus name refers to a local, Isle of Wight term, ‘caulkhead’ in what workers were called who caulked ships for a living in the Solent shipyards; Species name, trimicrodon, means ‘three small teeth’ in reference to three pairs of teeth at the front of the mouth that were half the size of the next pair of teeth; From Isle of Wight, fossil remains were discovered on Yaverland Beach in a brown clay layer belonging to the Wessex Formation; The maxillopremaxillary suture had a slight posterior descent; Rostrum (beak) had 10 small pairs of alveoli (singular: alveolus ~ bony socket serving as the root for a tooth); Alveolus pair 3 was the largest followed by pair 2; Pairs 1-4 and 8-10 were the larger pairs, with pairs 5-7 being the smallest; Slightly larger than the 5-7 pairs, the  9-10 alveoli pairs weren’t parallel as the other pairs, but staggered; In the 1 and 9 alveoli, of the right side, replacement teeth were forming; At the tip of the jaws, the first two pairs of smooth concave teeth were frontward pointing; Going down the jawline, the teeth oriented more outwards, while the posterior teeth were more perpendicular to the jaws. From the back of the skull, a parietal crest rose outwards in similar fashion as pteranodontids; It also possessed the characteristic ornithocheirid maxillopremaxillary crest.          

Bio Specs: With fossil remains found in terrestrial deposits where plant material was evident, this ornithocerid probably didn’t soar coastal seashores as the other members did, instead Caulkicephalus filled the niche in freshwaters along lakes, rivers, floodplains and lagoons; It still soared above water hunting for fish and other aquatic animals near the surface to snatch in its grasping and caging toothed jaws; Caulkicephalus was one of the largest pterosaurs to possess teeth.


Artist Franz Anthony

Species: Unwindia trigonus
Phonetics: Un-wind-ee-ah = tri go-nus
Family: Lonchodectidae
Wingspan: 2.3m/7.5ft
Diet: Carnivorous
Timeline: Late Cretaceous 112 mya

Description: Unwindia (honoring famed paleontologist, David Unwin); The species name, trigonus refers to ‘three angled’; Remains found in N.E. Brazil in the Araripe Basin where the Santana Formation has been exposed; Its lonchodectid relationship is closest to ornithocheirids; Had a very long lancet-like and slender rostrum (snout) that only supported teeth anteriorly in front of the nasoantorbital fenestra; The seven paired rows of homodont (similar) teeth were anchored in the fused maxilla/premaxilla by bony pedestals; This is unique among Unwindia and two other Lonchodectids: Lonchodectes and Yixianopterus; Distal coverage of the teeth were no more than 6cm/2.5in, which curved inwards as compressed cones at the front of the mouth; The maxilla/premaxilla fused suture extended toward the tip of the rostrum with no downward deflection; This exhibits most of the tooth-bearing part of the jaw in the maxilla; Premaxilla and maxilla fused but distinct; The nasoantorbital fenestra housed the nostrils and facial sinus cavity; The skull lacked a sagittal crest; Palatal surface displayed a raised dental border and a prominent palatal ridge flanked by deep sulci (singular: sulcus ~ a groove or furrow).          

Bio Specs: Considered small to pterodactyloid standards, Unwindia is still the largest known lonchodectid; The fossil was found in lagoonal and deltaic deposits and most likely, with the frontal teeth arrangement, preyed on small terrestrial, near shore or wading vertebrates; Having only frontal teeth might also allude to the fact that Unwindia used the toothed snout tip to root out animals from their burrows then latch onto them pulling the prey item out to swallow whole.
Artist: Joschua Knüppe
  
Species: Shenzhoupterus chaoyangensis
Phonetics: Shen-zoop-tuh-rus = kay-ah-ee-in-gen-sis
Family: Chaoyangopteridae
Wingspan: 1.4m/4.6ft
Diet: Carnivorous
Timeline: Early Cretaceous 120 mya

Description: Shenzhoupterus (‘Shenzhou wing’ in reference to Shenzou, the ancient name for China; The species name refers to the China city, Chaoyang and the suffix ensis meaning, ‘pertaining to’; Fossil remains are from the Lower Cretaceous of China’s, Jiufotang Formation; The most conspicuous detail of the skull was the large antorbital fenestra that extended over the eyes and nasal passages; This incorporated the nostril holes and orbitals (eye sockets); It as well had a arch-like crest that extended across the top of the full head, curving over the orbitals and ending in the back of the head where it made contact with a bony extension; Shenzhoupterus belongs to the pterosaur family that was totally edentulous (toothless) and are the most primitive of the azhdarchoids; The rostrum (beak) as toothless, was low with a straight or concave dorsal outline; While the anterior region of rostrum was low, the antorbital region expanded dorsally; Tip of rostrum downturned and expanded; Possessed limited in size elongate mid-cervical vertebrae with low blade-like neural spines; As opposed to predecessor pterosaurs, lacked lateral pneumatic foramina (singular: foramen ~ a hole in bone);    

Bio Specs: The Jiufotang Formation represents a swampy terrestrial and lacustrine environment; From these deposits it is safe to say that Shenzhoupterus was carnivorous and not wholly dependent upon a fish diet; This pterosaur most likely, from air or land stalked small vertebrates, piercing or snatching their prey then gulping them down whole; It may have supplemented its diet with fish along lakeshores spearing them with its pointed beak; It may also have scavenged on larger carcasses; Shenzhoupterus was small and most likely was on the menu for other predators; Being small with long slender wings, it must have been a very agile flyer over land or water.

Artist: Nobu Tamura

Species: Nurhachius ignaciobritoi
Phonetics: Nur-ha-chy-us = igg-nass-ee-oh-brit-wah
Family: Istiodactylidae
Wingspan: 2.5m/8.2ft
Diet: Carnivorous/Scavenger/Piscivorous
Timeline: Early Cretaceous 120 mya

Description: Nurhachius (honors Quing (Ch’ing) Dynasty ruler, Nurachi); Species name honors Brazilian paleontologist, Ignácio Aureliano Machado Brito; Fossil remains come from China’s Jiufotang Formation; Closely related to Isle of Wight’s only istiodactylid, Istiodactylus and ornithocheirids; Separated by thousands of miles, this shows how quickly istiodactylids diversified; The skull’s antorbital fenestra took up 58% of total skull length; Teeth were seated in frontal portion of jaws; Dentary were small, tapered, pointed and triangular; Two really small teeth anteriorly projected from tip of the lower jaw; The beak was long and tapered with lower jaw ending in a slight upwards curve; The scapula and coracoid bones are fused into a scapulocoracoid; End of humerus is wider than proximal end with no pneumatic opening; The atlantoaxis of cervical vertebrae is fused.

Bio Specs: Many pterosaur fossil remains, among other animal species have been found in the terrestrial deposits of the Jifutang Formation, Nurharchius remains are also among them; With strong cutting and slicing teeth and powerful jaw muscles, this pterosaur could wrestle with bigger prey; For the most part, Nurharchius hunted land prey, but as a generalist carnivore would also scavenge carcasses, take aquatic shore animals, including a supplemental portion of fish added to its diet.  
  
Artist: Joschua Knüppe

Species: Aymberedactylus cearensis
Phonetics: Aim-bare-uh-dack-till-us = see-air-in-sis
Family: Tapejaridae
Wingspan: 2m/6.7ft
Diet: Frugivorous/Herbivorous
Timeline: Early Creataceous 108 mya

Description: Aymberedactylus (small lizard finger); Aymbere is the native Tupi word for ‘small lizard’; Species name, cearensis honors the Brazilian state of, Ceará where remains were found, while the Latin suffix, ensis means ‘pertaining to’; Fossil remains are from the Crato Formation of N. E. Brazil’s, Araripe Basin; Aymberedactylus is the most basal in its taxon group differing in having no convexity interrupting the concave floor of the mandibular symphysis like other taperjarids; But, with the presence of taperjarid deep symphyseal bone grooves, Aymberedactylus is pleisiomorphic (ancestral trait state derived from a trait state); Therefore, Aymberedactylus diverged earlier than other tapejarid members; Is considered a sister to evolving azhdarchoids; Although the skeletal bones and the mandibular symphysis (where the two mandibles meet at tip of lower jaws) are fused; But due to the quadrate (squarish skull bone which articulates the jaws) exhibiting rough, rugose textures of the articular surfaces being characteristic of a not fully grown reptile, the fossil find is considered to be a subadult; This condition indicates incomplete ossification; The skull supported a short toothless beak; There was a cranial crest and one smaller chin crest with both being longer than tall; Small neurovascular foramina were evident in the rostrum (beak) indicating a keratinous (horned) sheath over the tip of the jaw; Consisting of the jaws, the bucca (mouth area) was y-shaped.         

Bio Specs: Sedimentary deposition where Aymberedactylus remains were found came from a coastal near shore lagoon; This was a time when a shallow warm inland sea formed over Brazil as the South Atlantic was opening up into a long narrow shallow sea; Angiosperms had replaced gymnosperms, so flowering and fruiting plants were in abundance; With relatively wide jaws compared to the shorter dentary fossa (hollows in the anterior bone of lower mandible), this pterosaur’s bite was not particularly strong; Aymberedactylus, with what was offered to forage on, evolved into a frugivore and herbivore; Thus, this toucan-looking pterosaur filled a niche while eradicating competition of other pterosaur carnivores/piscivores.
Artist: Julio Lacerda

Species: Guidraco venator
Phonetics: Gwe-dra-ko = vin-uh-ter
Family: Boreopteridae
Wingspan: 5m/16.4ft
Diet: Piscivorous/Carnivorous?
Timeline: Early Cretaceous 124.6-120 mya

Description: Guidraco (Chinese for ‘malicious phantom dragon’); The species name, venator is the Latin word for hunter; Fossil remains from N. E. China’s Jiufotang Formation; It has a very close anatomical relationship to the  anhanguerid  genus, Ludodactylus, but differs in Guidraco having elongated premaxilla and mandible tip frontal teeth directing outwards, an oval shaped frontal crest and absence of a lacrimal process; Also geographically, Ludodactylus hailed from what is now Brazil, in which 110-125 mya, even though South America had not completely split off from Africa, was still thousands of miles away from China; Guidraco’s skull was very elongated with the rostrum (snout) reinforced by the nasoantorbital fenestra being short; The tall oval crest was supported by the skull’s frontals; Distinctive teeth rows mirrored each other in the upper and lower jaws exhibiting the first at the tip as being overtly long pointing outwards and forward; The next three were even longer, slightly recurved and pointed downwards; Further down the jawline the teeth incrementally became smaller ending in the thirteen rear teeth being smooth and diminished in size; Nearing the jaw’s midline, the teeth had vertical ridges on the back of their enamel; Moderately elongated neck vertebrae were keeled possessing large pneumatic openings on the sides.         

Bio Specs: The strata fossil remains were found in is terrestrial deposition of swampy environments; Guidraco was terrestrial frequenting freshwaters to capture fish with its enmeshing front teeth; With webbed hind feet it had the ability to swim, but could not become stationary as it could not float; Snatching fish from just the beneath the surface, or chasing after fish in shallows diving to snare them; There is argument, in particular from Brazil’s paleontologist, Alexander Kellner that in fishing with the long needle-like sharp teeth, Guidraco had a high risk of impaling fish prey in the teeth; Essentially, with very weak and small forelimbs, the pterosaur would have no way to remove the obstacle and eventually die; Instead Kellner suggests, with a long tongue, it would probe small burrows rooting out the inhabitant vertebrate where Guidraco would capture it and if edible, eat it; On the other hand, Guidraco coprolites have been discovered with fish scales in them; So Kellner has a hard debate to win over consensus.

Artist: Julio Lacerda

Species: Liaoningopterus gui
Phonetics: Lee-ow-ning-op-teh-rus = goo-ee
Family: Anhangueridae
Wingspan: 5m/16.4ft
Diet: Piscivorous
Timeline: Early Cretaceous 120 mya

Description: Liaoningopterus (‘Liaoning wing’ referring to the Chinese province of, Lianoning where the fossil remains were found) The species name, gui is in tribute to Chinese paleontologist Gu Zhiwei; Fossils discovered in N.E. China’s Jiufotang Formation near Chaoyang, Liaoning; Liaoningopterus as a basal anhanguerid, is closely related to ornithocheirids; In fact some literature still lists this pterosaur under the family, Ornithocheiridae; Skull was low in the front and high posteriorly; The skull supported two crests with two low humped ones at the tip of the jaws on the upper and lower beaks; Teeth restricted to the proximal (the center of a body at the point of attachment) part of the jaws; At 81mm/3.2in, the fourth tooth is the largest pterosaur tooth found thus far; With variable tooth lengths, scientists concluded it was from erupted teeth replacements; The back of the mouth was toothless;    

Bio Specs: Liaoningopterus’ remains come from terrestrial deposits of rock protrusions into lakeshores; Thus far is the largest pterosaur discovered in Asia; With its long wings, long narrow snout and large front teeth, it was adept at aerial fishing; It soared above bodies of freshwater searching for fish just below the surface; While in flight, would swoop down to capture fish near the surface; Most likely roosted in rocky outcrops near lakeshores or in large trees.

Artist: Joel J. Rane

Species: Thalassodromeus sethi
Phonetics: Fah-lass-oh-dro-meus = seh-thee
Family: Thalassodromidae:
Wingspan: 5.3m/17.4ft
Diet: Generalist carnivore/omnivore
Timeline: Early Cretaceous 108 mya

Description: Thalassodromeus (sea runner); Species name, sethi refers to the Egyptian god, Seth due to head’s crest form; Fossil remains come from Brazil’s Santana Formation of the Araripe Plateau; Thalassodromids were a sister group to azhdarchidcoid pterosaurs evolving into chaoyangopterids and tapejarids; For the more derived pterosaur, the neck was shorter than most; The lower orbit of the skull was virtually ossified; The postorbital process of the jugal was at right angles to the jawline; The posterior jugal bone was deep; Two fenestrae perforated the crest above the orbit; The skull had a vastly expanded rostral and cranial crest that was combined expanding further posteriorly behind the braincase; Crest was subtriangular shaped and bony that was irrigated by blood vessels; Rostrum (beak) and jawline were narrow and streamlined ending in a point; This created a scissor-like bite.  

Bio Specs: Deposits the remains were found in were of coastal lagoons and forested terrain; It was first suggested that Thalassodromeus was a skimmer like the modern seabird, the black skimmer; As much as the name, Thalassodromeus (sea runner) is a misnomer, so are those that predicated Thalassodromeus as a skimmer; The black skimmer has extensive muscles that absorb skimming stresses to the jaws, head and neck; No pterosaur, in particular Thalassodromeus with its extremely streamlined rostrum could have withstood these stresses; Biochemical analysis prove that Thalassodromeus could not soar above the seas while skimming; If anything, at best it may have frequented coastal shorelines for scavenging; With powerful hind limbs, may have been the only pterosaur capable enough to have grabbed fish in shallow lagoons; But for the most part, in having the capacity to run was a terrestrial hunter chasing down and spearing vertebrates to dispatch, or picking off invertebrates like worms and insects; In particular juveniles would’ve been more inclined to eating invertebrates; With a cascade of newly evolved flora, it may have supplemented its diet with plant material. From the fossil record, it seems as soon as Thalassodromeus appeared...it disappeared.

Artist: Mark Witton


Species: Arambourgiania philadelphiae
Phonetics: Uh-ram-bur-gan-nee-uh = fil-uh-del-phi-eye
Family: Azhdarchidae
Wingspan: ~ 10m/32.8ft
Diet: Carnivore;
Timeline: Late Cretaceous 72.1-71 mya

Description: Arambourgiania (Arambourg’s giant); This pterosaur was first named by French paleontologist, Camille Arambourg with the genus name, Titanopteryx; After it was found that a simulid fly had already been described with that genus name; Later, Russian paleontologist, Lev Nesov renamed it, Arambourgiania in honoring Arambourg who had conducted the first comprehensive study of the remains; Species name, philadelphiae refers to the ancient Asia Minor city, Philadélpheia; Was closely related to thalassodromids with wing-fingers taking up less than half of wing length; As an azhdarchid, the orbits were depressed low into lower half of skull; Jaws would have been long and spear-like; Rostra would have been elongate; The humeri was pterodactyloid derived and was only two-thirds as long as the bodies’ torso; Cervical vertebrae were tube-like in structure.          

Bio Specs: Fossil remains laid down in shallow coastal waters no more than 30.48m/100ft of N.W. Jordan’s, Wadi Umm Formation’s sedimentary deposits of carbonate muds, chalks and limestone and Western Tennessee’s, Coon Creek Formation composed of sandy marled deposits from encroachment of, Mississippi Ebayment, a bay of the Gulf of Mexico;  Just east of ebayment’s reach, a marshy lowland was formed bordered by limestone bluffs; Sluggish rivers annually dumped large amounts of flora debris, in particular tree material but also occasional dinosaur and other animal carcasses; This is the environment the fossil remains of, Arambourgiania were laid down in the U.S.; This demonstrates that Arambourgiania was terrestrial frequenting coastal shores; Was not the largest azhdarchid; That title goes to Quetzalcoatlus (Phonetics: Kwet-zal-co-at-las) and Hatzegopteryx (Phonetics: Hat-zeh-gop-teh-rix); Azhdarchids are known for long necks and Arambourgiania was no exception; Neck was ~ 3m/9.8ft; It also possessed long and strong muscular hind limbs; Walked as a quadruped in pacing strides; This pterosaur was a carnivorous hunter, hunting down any vertebrate prey it could swallow whole; Diet included any smaller vertebrates to small dinosaurs. At rest, the wing fingers could not be folded upwards beyond the back simply because they couldn’t reach that distance. 

Artist: Jon Hughes

Species: Pteranodon longiceps  
Phonetics: Tuh-ran-oh-don = lon-juh-seps
Family: Pteranodontidae
Wingspan: Male 6.6m/21.6ft Female 3.8m/12ft
Diet: Piscivorous
Timeline: Late Cretaceous 88-80.5 mya

Description: Pteranodon (toothless wing); Species name, longiceps is Latin meaning, ‘long headed’; Fossil remains have all been found in North America in present states of, Kansas, Nebraska, Wyoming, South Dakota in the Niobrara Formation and Pierre Shale Formation and the Mooreville Formation of Alabama; The backbone consisted of neural spines on each vertebra and plate-like bony ligaments that strengthened vertebrae above hip; The ten short caudal vertebrae were fused resulting in a stiffened tail; Total tail length was 25cm/9.8in; The neck vertebrae were flexible; As one of the largest pterosaurs, Pteranodon’s mass was only 18.6kg/41lb to 25kg/55lb; It stood at 1.8m/6ft. The body was dwarfed in comparison to the wings and head; Possessed three clawed fingers and four clawed toes; The crest anchored from the cranium had two frontal bones extending upwards and backward from the head; The lower jaw was shorter and thicker creating an overbite; Through vestiges of female hip structure, the pelvis was wider than the much larger male’s; This allowed for easier passage of egg laying; Fusion of the scapula and coracoid were evident in mature specimens.       

Bio Specs: Chalk deposition of Niobrara Formation represented the accumulation of coccoliths (eukaryotic phytoplankton) during the transgression of the Western Interior Seaway into North America overlain lain by dark-gray shales of Pierre Shale Formation; Alabama’s Coastal Plain section was also an encroaching seaway as the Gulf Coast was opening up; Deposition is composed of chalk, clays, sand, silt and limestone;  Pteranodon is the familiar pterosaur we all envision with the cranial posteriorly protruding crest; Plus, in not only being the first toothless pterosaur found, there have been over a thousand fossil remains discovered thus far; The most characteristic trait is the extremely long crest but it made the pterosaur front heavy to swim by keeping the nostrils near the waterline, which would obstruct neat/clear breathing; Pteranodon was not a glider, but a flyer; Flying low near the surface it would snatch fish just below the surface; Wing shape and proportions reveal that pteranodons flew like an albatross catching air currents and soaring; Catapulting from the ground, with strong forelimb thrusts then an energetic flap of the wings would get it airborne; On land was adept as a quadruped, but bipedalism was also possible if needed; Fish was the main menu evidenced from numerous Pteranodon remains having fish material within the stomach area.    

Artist Julio Lacerda

Species: Nyctosaurus gracilis
Phonetics: Nick-toe-sore-us = gra-sill-lis  
Family: Nyctosauridae
Wingspan: 1.9m/6.2ft
Diet: Piscivorous
Timeline: Late Cretaceous 85-84.5 mya

Description: Nyctosaurus (night wing); Species name, gracilis is New Latin meaning ‘slender’ or ‘graceful’; All fossil remains have only been found in U.S.A. Kansas’ Niobrara Formation in the Smoky Hill Chalk Member; Most closely related to pteranodontids; Along with the nyctosaurid genus counterpart, Muzquizopteryx (Phonetics: Muz-kwee-op-teh-rix), were smaller than contemporary pterodactyloids; With long wings and anatomy was very similar to pteranodontids; Distinguished by scapular arch, in which the coracoid is not co-ossified with the scapula as in pteranodontids; Also, scapula has no articulation at the distal end being comparatively thin and expanded; Both nyctosaurid genera as well, had lost their forelimb three fingered claws and the fourth phalanx of the winged finger; Had a long sharp pointed beak; Most distinguishing feature of Nyctosaurus was the cranial crest consisting of two spars branching off from the bony base; The front spar at best was a bit longer and tilted forwards, while the back spar angled up and backwards; Was much confusion when crests were first discovered; Was first thought that the crest supported a skin sail, due to the fact that the first Nyctosaurus reviewed had a broken posterior spar making it appear shorter, perfect dimensions for a sail mast; The crest did not support a skin sail, nor was it even covered with keratin as all pterosaur crests had; The numerous crest spar fossils were all smooth and rounded in form suggesting no keratinous attachment; When viewing Nyctosaurus pictures, earlier ones will have them with the crest spars covered; Remember, this is not the case; The transition between bone and soft keratin is obvious in pterosaur fossils, with flattened bony spars having rough edges at the transition point; This feature is not evident in Nyctosaurus fossils; From innumerable remains, young and subadult fossils have been found and studied.

Original artwork: Dmitry Bogdanov

Bio Specs: Based on forelimb musculature, total weight, and total wing surface area versus loading, in a study, Nyctosaurus could cruise during flight at 9.6m/31.5ft per second; This translates to 34.5 km/21.4 miles per hour; Walked on the forelimbs’ digit stubs; Could not cling to trees or cliffs, so when not grounded was in flight; Were strong flyers and practiced dynamic soaring; The crest would not have affected flight as it was very light; Both sexes possessed a crest although males were largest; Sub adults did not have a crest; From fossil record, it appears crests continually grew throughout adult life; If crest was for sexual display, oldest males had the advantage in attracting a mate; Also hypothesized is that the crests were a signal from those catching fish stating to others still searching, ‘here is where the fish are’; Nyctosaurus flaplings matured into adults within a year; Living along the shoreline and coastal regions of the, Western Interior Seaway, Nyctosaurus dieted on fish and perhaps softer small aquatic invertebrates; It plucked them form the water’s surface with its pointed beak either storing the catch in its pelican-like throat pouch or immediately swallowing it whole.      

Afterthoughts:
With the vast diversity in pterosaur morphology and ecology, there were great differences in size, teeth and beaks, skull size and shape, neck length, wingspan, wing shape, leg length, foot size and niche fits. This allows different animals to exploit different foods and environments from small woodland forms that caught insects in flight with snapping jaws, to flamingo-like filter feeders with thousands of teeth that lived on lakes, to blunt toothed clam crackers that patrolled coastlines, to toothless fruit eaters, to scavenging carcasses and to huge toothless marine forms that hunted fish far out to sea. Soft tissue preserved in some fossils can tell us about beaks, wings, and the pterosaur body covered in a sort of reptilian hair called pycnofibers.

Artist: James Kuether  Quetzalcoatlus
Towards the end of the Cretaceous, most pterosaurs were huge as in the humongous azhdarchids, hatzegopteryx and quetzalcoatlus. There just weren’t anymore small pterosaur finds during this period. The guessing went that the established bird populations at the time out-competed the smaller pterosaurs for ecological niches in food and habitat. A 2016 find off the coast of Canada’s British Columbia on the island of Hornby, however has caused a pause for rethinking.

Artist: Julio Lacerda  Hatzegopteryx


Artist : Mark Witton
A recent pterosaur fossil find shows an adult pterosaur to have had a wingspan of nearly 1.5m/5ft, but the body was the approximate size of a cat. This most recent find still has not been assigned a species recognition yet, so is going by its catalogued identification as, RBCM.EH.2009.019.0001, or simply in the name of, Hornby pterosaur.

Artist: Mark Witton  Azhdarchid Hornby pterosaur
The Hornby pterosaur possessed an unwarped deltopectoral crest, a parallel-sided and straight shaft, and slender bone walls which were typical of humeri in large-headed, toothless pterosaurs. It’s lack of a diaphyseal expansion corresponds well with the humeri in neoazhdarchian azhdarchids, such as Quetzalcoatlus. Its oval cross section of the humeral diaphysis is not oriented, as in most pterosaurs, but with the long axis perpendicular to the deltopectoral crest. This is a similar morphology that occurs in the holotype humerus of the azhdarchid, Hatzegopteryx. So, although small, it belonged to the family of the gargantuan pterosaurs and proves that at least some small pterosaurs still predominated during and all the way to the end of the Cretaceous.

Although it appears that this little pterosaur had found a successful niche among birds, after the end of the Cretaceous, this little guy along with all its other pterosaur and dinosaur brethren had gone extinct.

On another note, we do for the most part wish that these magnificent extinct animals could still be around; so much so, that we invent things up to insist they are still among us. Take for instance the video below. It certainly looks real, but is a drone mimic of a pterosaur...good effects though from a distance.



Well, for you...real or fake? Most likely this is either a readily available on the market drone pterosaur, or a radio controlled one. As viewed in the video below, one could also be a purchased mechanical pterosaur that looks awesomely similar to the one in the amateur video below. It runs on tracks though but is now much more advanced than the one in the video. With some CGI digital affects for special effects and a longer track, this would make for interesting viewing. This is a well-managed video, but the wing flaps would not have been characteristic of a live pteranodon (as this is what is portrayed), for the flaps have no thrust for lift.



Below is a fairly decent pterosaur video put out by the British Broadcasting Company (BBC). When ya get time, take a gander, click the link below and watch it. It’s worth a few minutes of time.

https://www.youtube.com/watch?v=bP3JkC0FyMI

In the next ‘Et Tunc Nulla Erat’ series, we will examine the evolutionary process of everyone’s favorite...dinosaurs and birds.


Here’s to hoping ya never tear-a-sore,
BJA

August-September 2017

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