Deltopecten

Belongs within: Pectinida. Deltopecten is a genus of scallops known from the Late Permian of Australia (Cox et al. 1969). Characters (from Cox et al. 1969): Large, orbicular, radially plicate shells with or without fine costae; ligament area striated more or less parallel to hinge axis, resilifers lacking. <==Deltopecten Etheridge 1892DX84 |–D. clarkei Fletcher 1929F71… Continue reading Deltopecten

Baltoceratidae

Belongs within: Orthoceratia. The Lower to Middle Ordovician Baltoceratidae were a family of relatively large orthoconic early cephalopods. Characters (from Furnish & Glenister 1964): Smooth, longiconic orthocones with moderately large marginal siphuncle, orthochoanitic septal necks and thin homogenous connecting rings. Baltoceratidae [Cochlioceratidae]K93 |–Murrayoceras Foerste 1926FG64 | `–*M. murrayi (Billings 1857) [=Orthoceras murrayi]FG64 |–Ogygoceras Ulrich, Foerste… Continue reading Baltoceratidae

Spyroceras

Belongs within: Pseudorthoceratidae. Spyroceras is a Devonian genus of orthocerid cephalopod recorded from Europe and North America. Characters (from Sweet 1964): Annulated orthocones with straight transverse sutures, transverse or slightly oblique surface annulations, and faintly cyrtoconic apices. Surface variously ornamented, longitudinal lirae conspicuous from earliest stage. Siphuncle central or slightly ventral; siphuncle orthochoanitic with forward-growing… Continue reading Spyroceras

Troedssonellidae

Belongs within: Orthoceratia. The Troedssonellidae were a Lower to Middle Ordovician family of orthocerid cephalopods that formed endocones in the apical part of their siphuncles. Characters (from Sweet 1964): Siphuncle suborthochoanitic; continual endosiphuncular lining of parietal deposits prolonged adapically to form endocones. Troedssonellidae [Buttsoceratidae, Troedssonellina]S64 |–Tajaroceras wardae Hook & Flower 1976K93 |–Moridunoceras Evans 2005KE19 |–Oxfordoceras… Continue reading Troedssonellidae