Eudimorphodon

Eudimorphodon is a recently discovered pterosaur, and comes from shale laid down Upper Triassic rocks in Italy.

Eudimorphodon Temporal range: Upper Triassic,
MCSNB 2888 in Milan
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Pterosauria
Suborder:	Rhamphorhynchoidea
Family:	Eudimorphodontidae
Genus:	Eudimorphodon Zambelli, 1973
Species
E. ranzii Zambelli, 1973 (type) E. cromptonellus Jenkins et al., 2001

A nearly complete skeleton was found in 1973. This showed it was a member of the long-tailed sub-order of pterosaurs, the Rhamphorhynchoidea. Eudimorphodon was small in size, with 110 teeth packed into a jaw only 6 cms long. Teeth at the front are fangs, further back the teeth are small and multipointed, many with five cusps. This is unique among pterosaurs, whose teeth are usually of a simple conical form.

Stomach contents showed it had eaten a small fish, Parapholidophorus. The top and bottom teeth of Eudimorphodon came into direct contact with each other when the jaws were closed, especially at the back of the jaw. The teeth were multi-cusped, and tooth wear shows that Eudimorphodon was able to crush or chew its food to some degree. Wear along the sides of these teeth suggests that Eudimorphodon also fed on hard-shelled invertebrates.

Juvenile Eudimorphodon had somewhat different and fewer teeth, and may have eaten insects.

An unsolved puzzle is the flexibility of the tail, which lacks the very long stiffening vertebral extensions other long-tailed pterosaurs have. This flexibility is a basal trait; its functional significance in this genus is unknown. However, it is known that the stiffened tail of Rhamphorhynchus-like pterosaurs is a device which adds stability to their flight. Without this stability, the animal would be more manoeuvrable, but their flight would need more control by the brain.

Eudimorphodon Media

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  Fossil at Museo di Scienze Naturali, Bergamo, specimens MCSNB 8959 a,b

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  Eudimorphodon ranzii