LDEO Press Release on Skull Discovery

	OLSEN, P. E., Lamont-Doherty Earth Observatory of 	
		Columbia University,  Palisades, New York, 10964
	NORELL, M. A., Department of Vertebrate Paleontology, 	
		American Museum of Natural History, Central Park 
		West at 79th Street, New York, NY 10024-5192
	SUES, H.-D., Department of Vertebrate Paleontology, Royal 
		Ontario Museum, 100 Queen's Park, Toronto, Ontario  
		M5S 2C6, Canada
	McDONALD, N. G., Department of Earth and Environmental 
		Sciences, Wesleyan University, Middletown, CT 	

Tetrapod skeletal remains are regarded as particularly rare in the 
Triassic age portion of the Newark Supergroup, despite the extreme 
abundance of reptile footprints in some basins. In March, 1995, 
however, most of a skull of a small archosaur was found in the lower 
New Haven Formation, in Cheshire, CT. The skull, still incompletely 
prepared at the time of writing, consists of most of the right face along 
with a complete mandible in articulation, and a few displaced 
vertebrae. The skull is long and pointed, with recurved teeth that are 
thickly oval in cross section and limited to the anterior part of the 
snout. It has a triangular lower temporal opening and a backward 
slanted suspensorium. The anteorbital fenestra is large and the 
anteorbital fossa even larger, and appears triangular. The maxilla and 
jugal form a broad medially and ventrally directed shelf.
	In its overall form, it is comparable to the poorly known 
probable crocodylomorph Erpetosuchus from the Lossiemouth 
Sandstone of Scotland (see Newton, 1894). Further preparation should 
allow a more definitive identification. This is the first skull of a 
Triassic crocodylomorph described from eastern North America.
	The source of the material is an exposure in Cheshire 
consisting of gray, buff, and brown meandering river deposits 
alternating with red overbank deposits (McInerney (1993) and Horne 
et al., 1993). The skull was found in situ in an upright position in red 
sandy mudstone. The mudstone is intensely bioturbated by Scoyenia 
burrows and roots, and it passes upward into caliche-bearing red 
sandy mudstone comprising a typical New Haven Formation caliche 
paleosol profile. A pollen and spore assemblage from the basal part of 
the New Haven Formation (Cornet, 1977) constrains the age of the 
new skull to the Late Triassic, almost certainly to the Norian. 
	Previously described reptile taxa from the New Haven 
Formation include the type of Stegomus arcuatus (Marsh, 
1896) , an isolated, fragmentary scapula of a phytosaur ("Belodon 
validus": Marsh, 1893), a small sphenodonian skull (Sues and 
Baird, 1993), and an excellent skull and partial skeleton of 
Hypsognathus fenneri (Ostrom, 1967). The relative age 
relations of these taxa, apart from being Norian or Rhaetian, are 
	The bone-bearing fluvial facies at Cheshire is one of the most 
common types of fluvial facies in the Newark Supergroup, and it is 
noteworthy that a similar suite of lithologies in the Durham subbasin 
of the Deep River basin in North Carolina recently produced several 
partial skeletons of suchian archosaurs (Olsen et. al, 1996). Because 
this facies is almost never prospected for fossils in the Newark 
Supergroup, the dearth of skeletal remains in Newark Supergroup 
Triassic age strata may be more apparent than real.

Cornet, W. B., 1977, The Palynostratigraphy and Age of the Newark 
Supergroup. [Ph.D., thesis], Department of Geosciences, Pennsylvania 
State University, State College, Pennsylvania, 505 p.
Horne, G. S., McDonald, N. G., LeTourneau, P. M. and de Boer, J. Z., 
1993, Paleoenvironmental traverse across the early Mesozoic Hartford 
rift basin, Connecticut, In Cheney, J. T., Hepburn, J. C., Field trip 
guidebook for the northeastern United States, Boston GSA, 
Contribution - Geology Department, University of Massachusetts, 
v.67, Vol. 2, p. P.1-P.26.
Newton, E. T., 1894, Reptiles from the Elgin Sandstone-description of 
two new genera. Philosophical Transactions of the Royal Society of 
London, Series B, v. 185, p. 573.
Marsh, O. C., 1893, Restoration of Anchisaurus. American Journal of 
Science, 3rd ser., v. 45, p. 169-170.
Marsh, O. C., 1896, A new belodont reptile (Stegomus) from the 
Connecticut River sandstone. American Journal of Science,  4th ser., 
v. 2, p. 59-62.
McInerney, D. P., 1993, Fluvial architecture and contrasting fluvial 
styles of the lower New Haven Arkose and mid-upper Portland 
Formation, early Mesozoic Hartford Basin, central Connecticut. M.S., 
thesis, Department of Geology an Geography, University of 
Massachusetts; Amherst, 271 p.
Olsen, P. E., 1980, Comparison of the vertebrate assemblages from 
the Newark and Hartford basins (Early Mesozoic, Newark 
Supergroup) of eastern North America: In Jacobs, L. L. (ed.), Aspects 
of Vertebrate History. Flagstaff, Museum of Northern Arizona Press, 
p. 35-53.
Ostrom, J. H., 1967, [on the discovery of Hypsognathus in 
Connecticut]. Discovery, v. 3, p. 59.
Sues, H.-D. and Baird, D.,  1993, A skull of a Sphenodontian 
lepidosaur from the New Haven Arkose  (Upper Triassic Norian) of 
Connecticut. Journal of Vertebrate Paleontology, v.13, n.3, p.370-372.