The Early Evolution Of Archosaurs: Relationships And The Origin Of Major Clades
Author
Nesbitt, Sterling J.
text
Bulletin of the American Museum of Natural History
2011
2011-04-29
2011
352
1
292
http://www.bioone.org/doi/abs/10.1206/352.1
journal article
10.1206/352.1
0003-0090
5405335
Coelophysis bauri
(
Cope, 1887
)
, sensu
Colbert, 1989
(fig. 12J)
AGE: Late Norian–?Rhaetian, Late Triassic (
Heckert et al., 2008
).
OCCURRENCE:
Coelophysis
Quarry
, ‘‘siltstone member’’ of the Chinle Formation, Ghost Ranch, northern
New Mexico
.
HOLOTYPE
: AMNH 7224, complete skeleton missing the tail (the tail is reconstructed from other individuals).
REFERRED MATERIAL: AMNH 7223 (see
Colbert, 1989
) and any coelophysoid material from the
Coelophysis
Quarry
, including CM 31374, a complete skull.
REMARKS:
Coelophysis bauri
refers only to the small theropod collected from the
Coelophysis
Quarry
at Ghost Ranch. Even though it was cited as represented by a thousand skeletons (
Schwartz and Gillette, 1994
), few of the original specimens are fully prepared, and all of the specimens were subjected to crushing and distortion. Despite the distortion,
Coelophysis
remains the most completely known basal theropod available for study.
Coelophysis
differs from
Eoraptor
,
Herrerasaurus
, and
Staurikosaurus
in the more elongated dorsal vertebrae, five fused sacral vertebrae, dolichoiliacic ilium, presence of a small lateral projection on the distal end of the tibia, and the functionally tridactyl foot with a metatarsal I that is attached to metatarsal II and does not reach the ankle joint. It differs from
Gojirasaurus
in the relatively lower neural spines of the dorsal vertebrae and the significantly smaller size, from
Liliensternus
in the absence of a broad ridge that extends from the posterior end of the diapophyses to the posterior end of the vertebral centra in cervical vertebrae and the smaller size, from
Procompsognathus
in the larger overall size and the lower metatarsal III: tibia ratio, from
Shuvosaurus
in the lack of any of the derived cranial features of the latter taxon, and from the slightly younger, but very similar
Syntarsus
in the lack of a postnasal fenestra. (based on
Padian 1986
,
Colbert, 1989
, AMNH 7223 and 7224).
KEY REFERENCES:
Colbert, 1989
;
Rauhut, 2003
; Nesbitt et al., 2006.