A NEW SPECIES OF PROTOSCUTELLA (ECHINOIDEA, CLYPEASTEROIDA, PROTOSCUTELLIDAE) FROM THE MIDDLE EOCENE (LUTETIAN) SANTEE LIMESTONE IN BERKELEY COUNTY, SOUTH CAROLINA

A new species of protoscutellid clypeasteroid sand dollar, Protoscutella palmeri n. sp., is described and discussed. Specimens were collected from a quarry near Jamestown, Berkeley County, South Carolina in which the mid-Eocene Santee Limestone is exposed. The new species occurs below the strata containing Protoscutella mississippiensis mississippiensis (Twitchell), which can be collected in the same quarry. The new Protoscutella is distinguished by a greatly widened (alate) test, yielding a width to length ratio much higher than that found in the subpentagonal to slightly elongated test of its congeners. Also unique among Protoscutella, the periproct of P. palmeri n. sp. is consistently and strongly supramarginal throughout ontogeny. Material was preserved well enough to present details of the oral plate pattern, and analysis of this pattern in several specimens reveals that there is some variation among individuals in terms of the disjunction of the interambulacral plate columns, but that there is consistency in the plate counts to the periproct. Protoscutellid sand dollars are important index fossils in the middle and upper Eocene of the Carolinas. Protoscutella palmeri n. sp. is no exception, being stratigraphically one of the earliest members of the family Protoscutellidae, and the earliest in the Carolinas.