A new family and superfamily for the southern giant crab of Australia, Pseudocarcinus gigas (Lamarck, 1818) (Decapoda: Brachyura)

Abstract

Abstract The Australian southern giant crab, Pseudocarcinus gigas (Lamarck, 1818), has traditionally been placed in the families Oziidae Dana, 1851 or Menippidae Ortmann, 1893 (superfamily Eriphioidea MacLeay, 1838). Previous genetic studies questioned the validity of this classification as the molecular markers placed it far from all eriphioid lineages. A morphological re-examination of P. gigas shows that it possesses a suite of unusual characters in the structure of the antennae, antennules, epistome, carapace, pereopods, thoracic sternum, and vulvae that show it is different from other Eriphioidea as well as all other extant heterotremes, confirming the genetic results. A new family, Pseudocarcinidae, and a new superfamily, Pseudocarcinoidea, both monotypic, are here established for P. gigas.