A new classification of the Galatheoidea (Crustacea: Decapoda: Anomura)

Abstract

The high level classification of the Galatheoidea, popularly known as squat lobsters, has been relatively stable for almost a century. Multiple recent studies of their interrelationships, however, have revealed significant incongruities between the traditional classification and phylogeny. The Aeglidae, Chirostylidae and Kiwaidae were recently removed to other superfamilies. On the basis of previous phylogenetic analyses, we herein revise the higher classification of the remaining Galatheoidea to comprise four families: Galatheidae, Munididae fam. nov., Munidopsidae, and Porcellanidae. The galatheoid families are both morphologically and ecologically distinct. Members of the Munidopsidae are distinguished by the absence or reduction of the maxilliped 1 flagellum and usually occur in outer slope or abyssal habitats. Members of the Munididae fam. nov. are united by the trifid or trispinous anterior margin of the carapace and usually occur at outer shelf or slope depths. The Galatheidae includes primarily shallow water species, united by a broad, triangular rostrum, and is most closely related to the porcelain crabs, Porcellanidae. The families of the Galatheoidea are diagnosed and a diagnostic key provided. Extant and fossil genera are listed for each galatheoid squat lobster family.