230 Paleontology/Paleobotany (Posters) II: Fossils in Time, Space, and Morphospace

A NEW GENUS OF BELOSAEPIID (COLEOIDEA) AND ASSOCIATED, RARELY SEEN PHRAGMACONE STEINKERNS FROM THE CASTLE HAYNE LIMESTONE (EOCENE) OF SOUTHEASTERN NORTH CAROLINA

Paper number: 230-40
Program: Technical Sessions
Time: 1:30 PM – 5:30 PM

Authors

Abstract

World-wide, Tertiary coleoids, including sepiids, have been known since the 1800s. While in North America most systematic work was performed on specimens found in Tertiary deposits located along the Gulf Coast, little work has been done on specimens from the southeastern coast. Recently, several Eocene fossils locally referred to as ‘‘squid beaks'' or rhyncholites from the Castle Hayne Limestone exposed at the Martin Marietta quarries (near Castle Hayne, New Hanover County; near Rocky Point, Pender County; and near Richlands, Onslow County; North Carolina) were examined. Upon close examination of the sepiid guard-like sheath Belosaepia jeletzkyi Allen, 1968, we confirmed that our specimens represented internal hard parts of a cuttlefish-like organism similar to the belosaepiid guard-like sheath described by Jeletzky (1969); not rhyncholites or ‘‘squid beaks.'' Examination of type material representing Belosaepia jeletzkyi, and several other species of Belosaepia demonstrated marked differences among species of Belosaepia Voltz, 1830 and the specimens obtained from the Castle Hayne Limestone.

After thoroughly examining several hundred specimens recently collected from North Carolina we have revised of the taxonomic position of Belosaepia jeletzkyi Allen, 1968. We have erected a new genus, Anomalosaepia, consisting of four new species, A. alleni, A. mariettani, A. vernei, and A. andreanae from the Castle Hayne Limestone of southeastern North Carolina, as well as Belosaepia jeletzkyi from the Cook Mountain Formation of Louisiana.

Additionally, while workers have focused taxonomic descriptions, or attempted phylogenetic reconstruction of coleoid lineages based on the guard-like sheaths, phragmacones of these organisms are virtually unknown. Recently, two distinct types of coleoid phragmacone steinkerns have been found in spoil piles exposed at the Martin Marietta Quarry, near Castle Hayne, New Hanover County, North Carolina. Careful examination of the phragmacones has led us to assign the moldic casts to the genera Beloptera? sp. and Anomalosaepia sp.

Together, the newly described genus Anomalosaepia, consisting of five species of guard-like sheaths, and the associated phragmacones, may provide the basis for a thorough phylogenetic reconstruction of Eocene sepiid lineages.