New Species Of Lizard Found In Stomach Of Dinosaur

A team of researchers has discovered a new specimen of a microraptor -- volant dromaeosaurid Microraptor zhaoianus -- with the remains of a nearly complete lizard preserved in its stomach. The researchers have named the lizard after Lord Indra. 

The lizard is unlike any previously known from the Cretaceous and represents a new species- Indrasaurus wangi. The name Indrasaurus was inspired by a Vedic legend in which the god Indra was swallowed by a dragon during a great battle (the dragon here referring to Microraptor).

The lizard was named after Prof WANG Yuan from IVPP, who is also director of the Paleozoological Museum of China. Professor WANG is an expert on the paleoherpetofauna of China and has been in charge of numerous exhibitions of Chinese fossils.

The research team ran the most extensive phylogenetic analysis of Cretaceous lizards ever conducted and showed that all known Cretaceous species were more closely related to each other than to any modern lineage.

Details of the study were published in the Journal of Current Biology.

The new lizard had teeth unlike any other previously known from the Jehol Biota, thus expanding the diversity of this clade and possibly suggesting a unique diet for this new species.

This is the fourth documented occurrence of a Microraptor preserving stomach contents - this dinosaur is now known to have fed on mammals, birds, fish, and lizards, supporting the interpretation that it was an opportunistic predator.

The lizard is nearly complete and articulated, showing that it was swallowed whole and head first, meaning that Microraptor fed in a manner similar to living carnivorous birds and lizards.

Although the Jurassic troodontid Anchiornis has been recently demonstrated to have egested pellets similar to extant carnivorous birds (most famously documented in owls), this ability was apparently absent in Microraptor, further adding to the evidence that the evolutionary transition from dinosaur to bird was characterized by extreme homoplasy - that is, numerous traits evolved multiple times independently in closely related groups.

Over the past 20 years, direct evidence of trophic interactions in the Jehol Biota has slowly accumulated. There are now 20 predator-prey relationships documented through direct evidence of stomach contents.