Ornitholestes - Discovery and Naming

Discovery and Naming

Ornitholestes was the first theropod to be discovered in the 1900s. The holotype skeleton (AMNH 619) was excavated in July 1900 in the Bone Cabin Quarry in Wyoming by an American Museum of Natural History expedition by Peter C. Kaisen, Paul Miller and Frederick Brewster Loomis. It represents a partial skeleton with skull, including numerous elements of the vertebral column, the forelimbs, pelvis and hindlimbs. Henry Fairfield Osborn named and scientifically described the specimen in 1903. The genus name Ornitholestes, initially suggested by Theodore Gill, means "bird robber" and is derived from the Greek ὄρνις/ornis, ornithos ("bird") and λῃστήσ/lestes ("robber"). The species name (O. hermanni) honors Adam Hermann, the head preparator at the Museum, who directed the restoration and mounting of the skeleton.

An incomplete hand (AMNH 587) was assigned to Ornitholestes by Osborn in his 1903 description of the genus. However, as Gregory S. Paul (1988) noted, the poor preservation of the corresponding elements in the type specimen made this association "tentative." In 2005, Kenneth Carpenter et al. described a new small theropod, Tanycolagreus, whose skeleton was found in Bone Cabin Quarry only a few hundred yards from AMNH 587. Since AMNH 587 was virtually identical to the preserved hand of the Tanycolagreus type specimen, it is now considered to belong to that dinosaur and not to Ornitholestes. Following this reassignment, Phil Senter (2006) noted that "our knowledge of Ornitholestes can be drawn now only from the holotype." John Foster (2007) reported that some fragments from Dry Mesa Quarry may belong to Ornitholestes, though these have not yet been described.

In 1920 Charles Whitney Gilmore concluded that Ornitholestes was identical to Coelurus; in 1934 Oliver Perry Hay recognised only a difference at the species level, naming a Coelurus hermanni, but in 1980 John Ostrom revived the genus.