Was Rhamphorhynchus a skim feeder?

Whilst translating a passage from Peter Wellhofers' work on the Rhamphorhynchoidea, I came across this specimen from the collection of Karl Strobl.

Specimen No. 28: Fig. 24; Plate. 8, Fig. 1-3. Wintershof. Sammlung KARL STROBL, Eichstätt.
Part and counterpart of an entire skeleton with excellent preservation.

The individual is seen from the side; the arms are pushed forwards, the flight fingers in parallel with backbone extend backwards. Impressions of the flight skin and the narrow, lance shaped tail sail are present. The lower jaw extremity is relatively high, blunted in front. The upper edge line of the skull is concave. The front edge of the Infra-temporal opening is formed by the Quadrato-jugale. The cranial length measures 55.5mm.
The gastral skeleton consists of 6 curved bones still in situ; the middle pieces are displaced forwards. The Pubis is widened ventral, so that to the Ischium appears as a bay than rather a round opening. The Prepubis is strengthened centrally and hook-shaped (fig. 10 e).
Within the body cavity is a compressed fish tail and numerous single fish bone fragments indicating the stomach contents. Beside this lies 6-7mm long bananas-shaped small sausages like gastric stones of 1.5mm diameter and with zigzag-shaped textured surface (ref. fig. 44 b).

This specimen clearly shows that this individual had eaten a fish which was swallowed whole, head first. The use of gastric stones to aid mechanical digestion is an indication of a more specialised digestive system. This rhamphorhynchus may have had a gizzard, similar to that seen in birds, or a muscular and thick stomach wall to enable the churning of contents to allow the enzymes and gastric stones to break down the food both chemically and mechanically.

Very few pterosaurs give information about stomach contents, and in this case it leads to a question about fishing methods. Did rhamphorhynchus use a surface skimming technique to fish, or was it a shallow diver. It is impossible to say for certain, but the evidence is compelling. The jaws would certainly be able to scoop up a fish from near the surface of the water. and such a technique would have needed a very precise flying skill and good control of the jaws and neck.

The jaw on this specimen shows an impression of an upturned bony sheath at the end of the lower jaw. Such a structure, being free of teeth, would lend itself to surface skimming. This is a strong clue to the feeding habits of this type of Rhamphorhynchus and the group as a whole.

Wellnhofer, P. 1975 Die Rhamphorhynchoidea (Pterosauria) der Oberjura-Plattenkalke Süddeutschlands. Teil II. Systematische beschreibung. Paläontographica A 148, 132–186.

The Rhamphorhynchoidea

In 1975, Peter Wellnhofer wrote a classic monograph on the Rhamphorhynchoidea. This set of 3 linked works has been the baseline for the study of this group of pterosaurs since then. It is a well organised work with analysis split into skeletal morphology, systematics and Palaeoecology. The texts were originally in German and as far as I am aware, they have not been translated wholesale into English. Recently, I started to translate part 2 for my own use. I would love to publish my translation, which will be a new work, but the original text is not out of copyright until 2025. I can only find paper copy, but I have been told that there is an electronic copy in German. This has eluded me, so I am transcribing and translating from the original text.

Wellnhofer, P. 1975 Die Rhamphorhynchoidea (Pterosauria) der Oberjura-Plattenkalke Süddeutschlands. Teil I. Allgemeine Skelletmorphologie. Paläontographica A 148 , 1–33.11 plates.

Wellnhofer, P. 1975 Die Rhamphorhynchoidea (Pterosauria) der Oberjura-Plattenkalke Süddeutschlands. Teil II. Systematische beschreibung. Paläontographica A 148, 132–186.

Wellnhofer, P. 1975 Die Rhamphorhynchoidea (Pterosauria) der Oberjura-Plattenkalke Süddeutschlands. Teil III. Palökologie und Stammesgeschichte. Paläontographica A 149, 1–30. 13 plates

The problem in translating any text is the transfer of meaning. There are words in German that can have several possible meanings in English. This also works the other way around. The bulk of the meaning is transferable with a high level of confidence in the result, but there are some areas where the meaning has to be a best guess. This type of translation is often referred to as a Gist Translation. This means that in some cases, the reader may need to refer to the original text to grasp the full meaning of a sentance of passage. It is for this reason that translations should only be attempted from the original documents. Another of Peters texts that I have frequently used is the Handbook of Paleoherpetology, Part 19. This text is also only available in German, so people who are not able to read that language can only look at the wonderful line drawings and be amazed. This is of course, another text that sets the baseline for the study of pterosaurs in general. It is a little dated now, but still a valuable resource. The original text is still available to purchase on the Internet.

Wellnhofer, P. & Khun, O. 1978 Handbuch der Paläoherpetologie. Teil 19. Pterosauria. Stuttgart: Verlag Gustav Fischer.

These texts defined the study of pterosaurs for a whole generation of researchers. It would be beneficial to the subject to have them available on line both in their original German text and in English. The main difficulty is in gaining permission to freely allow access without infringing copyright law. Watch this space!

The Frog Mouthed Pterosaurs

Anurognathus ammoni, a pterosaur from the upper Jurassic Solenhofen limestones of Bavaria, was first published in 1923 by Dodderlein. This was recognised as a very unusual small pterosaur, having a very broad and short jaw. Nothing had been seen like this before. The specimen was poorly preserved and the bones were somewhat disarticulated, but the animal clearly has short blunt teeth which were not suited to tearing flesh. "Frog Jaw" was thought to be an insectivore, possibly catching is prey on the wing or on leaves and branches around forested areas.
A second, well articulated specimen of Anurognathus ammoni was described by Bennet in 2002 and this specimen shows the skeletal anatomy of the pterosaur very clearly.
Another frog mouthed species, Batrachognathus volans, is known from the Karatau Mountains, Upper Jurassic sediments of Kazakhstan. This species was described by Rjabinin in 1948. The specimen is a partial skeleton including a disarticulated skull which clearly shows a wide jaw. This specimen shows some similarities with Anuroghnathus, but enough differences to classify it as a different species.
Dendrorhynchoides curvidentatus is a Tithonian species that was collected from the Chaomidianzi Formation, Zhangijagou locality from the Lower Yixian Formation near Beipiao City, Western Liaoning Province, China. It was published in 1998 and is one of several fine specimens to come out of this part of China. This is a very good fossil of this type of pterosaur and it has been restored after a preparator doctored the fossil in an attempt to make it more salable.
Jaholopterus ninchengensis is a compete Anurognathid with some soft part preservation from the Lower Yixian Formation at Nincheng, Inner Mongolia. This specimen is known as the Nincheng Rehe Pterosaur and is in the Institute of Vertebrate Paleontology and Paleoathropology in Beijing. The specimen caused quite a stir when it was published in 2002.

These 5 specimens are the major contingent of the classification Anurognathidae. There are a few fragmentary remains, like a jaw fragment from the Middle Jurassic Stonesfield Slate which is in The National Museum of Wales, Cardiff. The Anurognathids were probably quite widespread in distribution, but I suspect that they were forest dwelling pterosaurs, living in places where fossilization is a rare process. The scientific community is probably quite lucky to have this many specimens of this pterosaur lineage to work with.

Döderlein L., 1923, Anurognathus ammoni, ein neuer Flugsaurier. Sitzungsberichte der Bayerischen Akademie Wissenschaften, math.-naturwiss. Klasse, 1923, München. Pp. 117- 64, figs. 1-7.

Bennett S. C., 2002, A second specimen of Anurognathus from the Solnhofen Limestone of South Germany. Journal of Vertebrate Paleontology 22 (supp. 3), 36A

Rjabinin A. N., 1948, Remarks on a flying reptile from the Jurassic of the Kara-Tau, Akademia Nauk, Paleontological Institute, Trudy, 15(1): 86-93, 1 plate, Moscow and Leningrad.

Ji S.-A. and Ji Q., 1998, A new fossil pterosaur (Rhamphorhynchoidea) from Liaoning. Jiangsu Geology 22(4): 199-206.

Wang X., Zhou Z., Zhang F. and Xu W., 2002, A nearly complete articulated rhamphorhynchoid pterosaur with exceptionally well-preserved wing membranes and "hairs" from Inner Mongolia, Northeast China. Chinese Science Bulletin vol. 47(3), pp. 226-232.

A very Peculiar Pterosaur

Pterodaustro is represented by a number of specimens from Argentina. There is a complete skeleton, a partial juvenile and an egg, just to mention a few. This unusual pterosaur is quite well represented in the fossil record, certainly enough is known to make a convincing reconstruction.
Most unusually, this was a filter feeder with a fine sieve of unusually adapted teeth that would have been ideal for filter feeding on small aquatic living organisms. This was the Flamingo of the ancient world!
The diagram of the skull shows the peculiar nature of this animals jaw. This pterosaur has more teeth than any other pterosaur. It is likely that it has more teeth than any other Dinosauromorph. It is also the first pterosaur where gizzard stones have been observed to be present.

The holotype, which was originally described by Bonaparte, is PLV 2571 and is a right humerus in the Institute Miguel Lillo, Universitat Nacional Tucuman, Argentina. Most of the specimens come from South America which is probably where the species evolved within a specific shallow water habitat, where zooplankton and phytoplankton were abundant.

In 2004 un-hatched egg containing a juvenile Pterodaustro, from the Lagarcito Formation in Central Argentina was described. The lacustrine deposits in which it was found are called the Loma del Pterodaustro and they are dated to about 100 million years ago. The specimen MHIN-UNSL-GEO-V 246 has been studied using electron micrographs of the egg shell suggesting a leathery shell. Ghosting of proteins can be interpreted within the shell structure which has yealded a significant amount of information about this pterosaurs eggs.

Bonaparte J F, 1970 Pterodaustro guinazui gen.et sp.nov.. Pterosaurio de la formacion Lagarcito, Provincia de San Luis, Argentina, Acta Geologica Lilloana, 10(10):207-226

Bonaparte J F, 1971 Descripcion del craneo y mandibulas de Pterodaustro guinazi (Pterodactyloidea - Pterodaustriidae), de la Formacion Lagarcito, San Luis, Argentina, Publ. Mus. Mun. Cienc. Nat. Mar del Plata, Pp. 63-272

Bonaparte J F & Sanches T M, 1975 Restos de um Pterosaurio,Puntanipterus globosus de foracion la Cruz, provincia de San Luis, Argentina, Actas Primeiro Cong. A

L. M. ChiappeA. Chinsamy, 1996, Pterodaustro's true teeth, Nature 379, 211 - 212 (18 January 1996)rgentino Paleont. Biostretigr., 2:105-113

Frey E., Martill D. M., Chong-Diaz G. and Bell M., 1997, New pterosaurs from the Lower Cretaceous of Chile. J. Vert. Paleont. 17 (3)

Codorniú L, Chiappe L.M. Early juvenile pterosaurs (Pterodactyloidea: Pterodaustro guinazui) from the Lower Cretaceous of central Argentina. Can. J. Earth Sci. 2004;41:9–18

Chiappe L.M., Codorniú L., Grellet-Tinner G. and Rivarola D., 2004, Palaeobiology: Argentinian unhatched pterosaur fossil, Nature. 432, pp. 571-572 (2 Dec 2004)

A Chinsamy, L Codorniú, and L Chiappe, 2008, Developmental growth patterns of the filter-feeder pterosaur, Pterodaustro guiñazui, The Royal Society, Biol Lett. 2008 June 23; 4(3): 282–285

Mary Annings Pterodactyle

On 21st May 1799, Mary Anning was born, daughter of Richard and Mary Anning of Lyme Regis, Dorset, England. During her life she collected curiosities from the beach at Lyme Regis and nearby coastal areas. She became a very proficient and knowledgeable collector of fossils and made a number of remarkable discoveries. She often referred to experts for advice and support and her main sources were William Buckland, Henry de la Beche and William Conybeare, who were able to develop their reputations on many of Mary's discoveries.

In 1828, Mary discovered a fossil pterodactyle (later named Dimorphodon macronyx) which she discussed with William Buckland. Buckland wrote a paper on this fossil and it was known to be the finest of the English pterodactyles. The remains are now in the Natural History Museum, London.
Shortly after the discovery, her brother Joseph made a sketch of the fossil skull. He used reconstituted belemnite ink from the finds on Lyme Regis Undercliff. This drawing is now held by the Philpot Museum, Lyme Regis - though neither the fossils or the sketch are on display as they are considered too valuable to be exposed to the public.
The remaining bones of the fossil find were almost a complete skeleton and an additional find revealed the whole of the animals tail. This was one of the few pterosaurs that enabled a complete reconstruction to be attempted. A second skeleton and skull (minus tail) gave a better insight into the association of the bones and over the years, several small bone finds have been made. Many of these are in private collections.



Thackray J. C. A., 1995, A catalogue of portraits, paintings and sculpture at the Natural History Museum London. Mansell: London. xii, 70pp.

Torrens H. S., 1995, Mary Anning (1799-1847) of Lyme : ‘the greatest fossilist the world ever knew’. British Journal for the History of Science, Vol. 28, pp.257-284.

Buckland W. 1829, On the discovery of a new species of pterodactyle in the Lias at Lyme Regis. Trans. geol. Soc. Lond. ser. 2, 3, 217–222, pl. 27.

Padian K, 1983, Osteology and functional morphology of Dimorphodon macronyx (Buckland) (Pterosauria: Rhamphorhynchoidea). Based on new material in the Yale Peabody Museum. Postilla 189.
Pierce P., 2006, Jurassic Mary, Mary Anning and the Primeval Monsters. Sutton Pp238.

Discovering Pterosaur flight - Part 2

The design of Flying model pterosaurs was taken a stage further in 1957 when Erich von Holst made a flying model of Rhamphorhynchus. This model was powered by a coiled elastic band which was connected to a rocker device which flapped the wings of the model. The tail sail had to be horizontal to stabilise the model in flight. From this experiment it was clear that the Rhamphorhynchus form had the potential to be a very good flying animal.

In the 1970's a bat expert (Cherrie Bramwell) and an engineer (R G Whitfield) teamed up to examine and analyse the joints of large pterosaurs. They defined the range of movement in the wing joints and proposed a postural model for Pteranodon. G R Whitfield had flown a fully controlled life size model in 1973, but that model was eventually destroyed in a crash landing. This work was an extension of the Hankin and Watson work and was to provide a basis for future flying models.
Stephen Winkworth was a model aeroplane builder who had an interest in anything that flies. In 1984 he designed a pterosaur flying model, based on the Bramwell and Whitfield work which was flown in January 1985 on the cliffs along the Dorset coast. The model was filmed for the BBC television production "Pteodactylus Flies". This 15 foot wingspan model was an excellent radio controlled glider, though to overcome some stability problems, additional stability fins had to be incorporated in the design.  

The Quetzalcoatus Project was started in 1984 and in December1985 Paul MacCready flew a half size flying model of Quetzalcoatlus. This flying model was much more sophisticated than the balsa and fabric model of Stephen Winkworth and used aviation technology for its construction. It had an autopilot device and a recovery parachute which could be controlled from the ground. The project was used to produce an IMAX movie in 1986 for the Smithsonian Air and Space Museum in Washington D. C.

Up to this point, the flying models of Pterosaurs had all been gliders or simple flapping models, using aeroplane aerodynamic theory in their production. The Stanford Project, which was supported by National Geographic was intended to build a flying model that worked like a real animal. This was an ambitious project and had an extensive team headed by Margot Gerritsen. The model flew in many forms, first taking to the air in 2006 with a stabiliser tail boom to allow the electronic movements to be tested. The model was air lifted and launched at altitude by a carrier plane. The Stanford model was nicknamed Herki and featured in the TV program "Sky Monsters", which is now available on video.


What next?......





Holst E. von., 1957, Der Saurierflug, Paleontologische Zeitschrift, 33, pp. 15-22. 7 figures.

Bramwell C. D. & Whitfield G. R., 1974, Biomechanics of Pteranodon. Philosophical Transactions of the Royal Society, London, B.267, pp.503-581

Winkworth S., 1985, Pteranodon flies again. New Scientist, 3 January 1985:32-33

MacCready P,, 1985, The Great Pterodactyl Project. Engineering and Science, November 1985: 18-24

Discovering Pterosaur flight - Part 1

In the early days of research, Samuel Thomas von Soemmering made the first sensible reconstruction of a pterosaur skeleton in 1812. The reconstruction was missing several skeletal elements, but was a sound model based on the available evidence. He also proposed a wing membrane form which, although too generous in area was a good attempt at theoretical reconstruction.
It was not until 1882 that the wing structure was known from the fossil record. A specimen originally named Rhamphorhynchus phyllurus was discovered in the Lithographic Shale of Bavaria. At about the same time an isolated wing known as the Zittel wing (above) was published. Both fossils showed the outline and structure of the wing membrane of Rhamphorhynchus. This enabled much better reconstructions to be made.

In 1910 C. F. Eaton produced a paper on the osteology of Pteranodon with a skeleton reconstruction This was an inspired paper showing the skeletal form of a large pterosaur. Pteranodon was only known from crushed and distorted remains and this paper showed the skeletal form in a realistic way.

Ernst Stromer was inspired by the Rhamphorhynchus wing membranes and he produces a flying glider in 1913 which demonstrated that Rhamphorhynchus could fly with the known wing form.

By1914 the Hankin and Watson paper on the flight of Pteranodon gave us an insight into the structure of large pterosaurs that was related to the way they could fly. The framework was set for some real flying models.

Watch this space.......

von Soemmerring, S. T. 1812 Über einen Ornithocephalus oder über das unbekannten Thier der Vorwelt, dessen Fossiles Gerippe Collini im 5. Bande der Actorum Academiae Theodoro-Palatinae nebst einer Abbildung in natürlicher Grösse im Jahre 1784 beschrieb, und welches Gerippe sich gegenwärtig in der Naturalien-Sammlung der königlichen Akademie der Wissenschaften zu München befindet. Denkschr. k. bayer. Akad. Wiss. math.-phys. Kl. 3, 89–158, plates.

von Zittel, K. A., 1882, Über Flugsaurier aus dem lithographischen Schiefer Bayerns. Paläontographica 29, 47–80 & pls 10–13.

Eaton, G. F., 1910, Osteology of Pteranodon. Mem. Conn. Acad. Art. Sci. 2.pp.1-38.

Marsh, O. C., 1882, The wings of Pterodactyles. Am. J. Sci. (3)23, 251–256 & pl. 3

Stromer E., 1913, Rekonstruktionen des Flugsauriers Rhamphorhynchus gemmingi, H. v. M., Neues Jahrb. Min. Geol. Pal., II, pp. 49-68.

Hankin E. H., & Watson D. M. S., 1914, On the flight of pterodactyls. Aeronautical Journal 18, 324–335.