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Quitmaniceras

Quitmaniceras is a small, compressed, fairly evolute ammonite from the lower Turonian of Grant County, New Mexico and Trans-Pecos Texas, included in the subfamily Acanthoceratinae. The shell has a carinate venter in juveniles and one that is arched in adults, usually with a raised siphonal line,(siphonal referring to the marginal siphuncle). Ribs are very weak to moderately strong, flexious, typically sloping forward toward the rim, bending further forward at the outer shoulder.