Chasmocarcinus Robertsi, A New Crab Species From the Miocene of Virginia, With Notes on The Genus Falconoplax (Crustacea, Decapoda, Goneplacidae)

Abstract

The new species Chasmocarcinus robertsi from the upper Miocene Eastover Formation of Virginia is described and compared to other closely allied living and fossil representatives of this genus. The comparative morphology of fossil and living species demonstrates that the fossil genus Falconoplax Van Straelen, 1933, is a junior subjective synonym of Chasmocarcinus Rathbun, 1898. Chasmocarcinus robertsi occurs in, or was derived from, Miocene strata, not "?Paleocene beds" as reported by previous authors. Specimens of C. robertsi found near Little Cove Point, Maryland represent the northernmost known occurrence of living or fossil Chasmocarci nus.