Paleogene Verrucidae (Cirripedia: Verrucomorpha) of North America, with descriptions of three new species

Abstract

In North America, Paleogene Verrucidae are rarely encountered. Only a single named species has been previously discussed by Zullo & Baum (1979), who provisionally assigned a Palaeocene form from North Carolina to Verruca rocana Steinmann, 1921. Eocene deposits in Washington State (USA) have now yielded two new species from intertidal to shallow water environments: Verruca gailgoedertae sp. nov. from the middle Eocene Crescent/McIntosh transition zone, and Verruca sorrellae sp. nov. from the upper Eocene to lowest Oligocene Gries Ranch and basal Lincoln Creek formations. Both species are characterized by punctate shell plates, and are placed in the lineage of Verruca stroemia (O.F. Müller, 1776). In Alabama, marls from the upper Yazoo Formation (Pachuta and Shubuta Members) have yielded Verruca alabamensis sp. nov., an uncommon deeper water form associated with abundant brachiopods and phosphate deposition. This last species shows no development of punctae and is not related to the lineage that leads directly to Verruca stroemia.

Scissurella nesbittae, new species, from the Gries Ranch Formation, Lewis County, Washington State (Gastropoda: Vetigastropoda: Scissurellidae)

“…Deposition of the Gries Ranch Formation likely occurred under subtropical conditions (Dickerson 1917;Van Winkle 1918) at depths of less than 100 m according to Effinger (1938), although Hickman (1984) has suggested that the Gries Ranch fauna may have been transported into deep water. A verrucid barnacle recently described (Perreault & Buckeridge 2019) from the Gries Ranch fauna might support Hickman's suggestion; living verrucids can be found from 0-620 m (Buckeridge 1997) and most living species are found in the deeper end of that range. The age of the Gries Ranch Formation has been considered to be either late Eocene (Lindberg 1987) Description.…”