NEW PENNSYLVANIAN SOMOHOLITID SPECIES FROM WHITE PINE COUNTY, NEVADA

Specimens of the new Pennsylvanian ammonoid, Somoholites n.sp., were recovered from the crest of Buck Mountain, White Pine County, Nevada. The strata that caps Buck Mountain was deposited in the Upper Pennsylvanian within the Strathearn Basin. Specimens occur in micritic concretions within this horizon and may be equivalent to the Hogan Formation described in the Pequop Mountains. Conodont species recovered from the ammonoid matrix indicate that the age of this unit is middle Desmoinesian. Conodont taxon occurring with Somoholites n.sp. include Idiognathodus podolskensis, Neognathodus asymmetricus, and Hindeodus sp. Most of the ammonoid specimens exhibit varied levels of preservation and all display some degree of fracture. One specimen was found with exquisite preservation and has proven very useful for classification purposes. The conch of Somoholites n.sp. is thickly discoidal to nearly globose and is comparable to Somoholites cadiconiformis(Wagner-Gentis, 1963). Somoholites n.sp. has a typical somoholitid suture pattern with wide rounded saddles and obvious pouching on its external lobes and prongs. The suture pattern of Somoholites n.sp. is similar to that of Somoholites merriami (Miller and Furnish, 1940), but differs slightly in degree of pouching and width of lateral lobes. The sutural pattern of Somoholites n.sp., however, is also dissimilar to that of Somoholites cadiconiformis(Wagner-Gentis, 1963) in curvature of pouching and directional orientation of prongs and lobes.