Zephyrosaurus

*Zephyrosaurus schaffi*

***Zephyrosaurus*** (meaning "westward wind lizard") is a genus of hypsilophodont ornithopod dinosaur. It is based on a partial skull and postcranial fragments discovered in the Aptian-Albian-age Lower Cretaceous Cloverly Formation of Carbon County, Montana. New remains are under description, and tracks from Maryland and Virginia have been attributed to something like it.

## Description

*Zephyrosaurus* is still very incompletely known. Among other distinctive characteristics, it had a steep face, a raised knob on the upper jaw, and a larger knob on the cheekbone. Some of the bones may have allowed movement within the skull (cranial kinesis) as well. Like other hypsilophodonts, it had beak teeth. It looks like a Lesothosaurus.

## Classification

Several studies have suggested that *Zephyrosaurus* and *Orodromeus* are closely related, mostly by virtue of both having bosses (described informally as "somewhat like an altoid") on their cheeks. Other studies have had difficulty classifying it, due to the sparseness of the original material. *Oryctodromeus* also shares several characteristics with *Zephyrosaurus* and *Orodromeus*, some of which may be related to burrowing. Thus, there may be a possible clade of burrowing hypsilophodonts from the middle to Late Cretaceous of Montana.

## Discovery and history

Hans-Dieter Sues named his new genus in recognition of the fossil being found in western North America, and Charles R. Schaff, who found the specimen. MCZ 4392, the type specimen, is composed of jaw fragments, the braincase and associated bones, several partial vertebrae, and rib fragments. He found the new genus to represent a previously unknown lineage of hypsilophodont, similar in some respects to *Hypsilophodon*.

Because of the fragmentary nature of the type, and lack of additional remains, *Zephyrosaurus* had not attracted much attention until recently, when two separate events brought it more recognition. First, Martha Kutter, in a 2003 abstract, reported on new remains of this genus under study at the Sam Noble Oklahoma Museum of Natural History, including the remains of at least seven individuals with bones from all regions of the body.

Then, Stanford et al. (2004) published on dinosaur tracks from the Patuxent Formation of Maryland and Virginia, which they named *Hypsiloichnus marylandicus* and attributed to an animal akin to *Zephyrosaurus* based on the proportions of the hands and feet.

## Paleobiology

*Zephyrosaurus* would have been a small, swift, bipedal herbivore. Like *Orodromeus* and *Oryctodromeus*, it may have burrowed as well.

## JPInstitute.com Description

Zephyrosaurus was a small plant-eating dinosaur that roamed parts of North America during the middle of the Cretaceous Period. These small dinosaurs were an important part of prehistoric life because they were probably a vital source of food for many other dinosaurs.
Some scientists believe that Zephyrosaurus was capable of cranial kinesis, or moving their jaws in directions other than a simple up and down chewing motion. It seems as if the wear patterns on some of the teeth suggest that the skull and jaws could move in other directions. Other skull plates also suggest the possibility of dynamic jaw movement.

## Links

https://web.archive.org/web/20080704173644/http://kids.yahoo.com/dinosaurs/432--Zephyrosaurus