A New Species of Spondylus (Mollusca: Bivalvia) from the Eocene of Alabama

Abstract

Some time ago Royal D. Suttkus, Professor of Biology, Tulane University, collected the paired valves of a moderately sized specimen of Spondylus from the Middle Eocene Gosport Sand, at the exposure on Little Stave Creek, near Jackson, Clarke County, Alabama (locality TU 306). The only previous record of the genus from the Middle Eocene of the Atlantic and Gulf Coast fauna has been by Harris (1919, p. 29) who reported "a fragment of Spondylus of dumosum type but too imperfect for further characterization," from the "St. Maurice Stage" (Cook Mountain Formation) west of Winnfield, Winn Parish, Louisiana. A second, Early Eocene specimen from Hatchetigbee Bluff, Alabama, reported by Harris (1897, p. 234, pl. 12, fig. 11) as Spondylus sp., is an incomplete upper valve that shows no trace of spines on the radial ribs, which also are of a wholly different shape and number than are those in the present specimen.