Pterodaustro

Pterodaustro was a pterosaur. It is found in the Lower Cretaceous of South America. Pterodaustro most likely fed on tiny invertebrates: zooplankton and krill.

Pterodaustro was medium-sized, with an adult wing-span of about two meters. It has only been found in Brazil.

Paleobiology
Pterodaustro probably waded in shallow water like flamingos, straining food with its tooth comb, a method called "filter feeding". Once it caught its food, Pterodaustro probably mashed it with the small, globular teeth present in its upper jaw.

At least two specimens have been found with gizzard stones in the stomach cavity, the first ever reported for any pterosaur. These clusters of small stones with angled edges support the idea that Pterodaustro ate mainly small, hard-shelled aquatic crustaceans using filter-feeding. Such invertebrates are abundant in the sediment of the fossil siteCodorniú L. et al. 2009. First occurrence of gastroliths in Pterosauria (Early Cretaceous, Argentina). XXIV Jornadas Argentinas de Paleontología de Vertebrados.

In 2004 a Pterodaustro embryo in an egg was reported. The egg was elongated, six centimetres long and 22 millimetres across and its mainly flexible shell was covered with a thin layer, 0.3 mm thick, of calcite.

Comparisons between the scleral rings (bony ring round edge of eye) of Pterodaustro and modern birds and reptiles suggest that it may have been nocturnal, and may have had similar activity patterns to those modern ducks which feed at night.

 References 

Category:Pterosaurs