New hermit crabs (Paguroidea, Anomura) from the Eocene of Huesca, Spain

Abstract

A new genus and two new species of fossil hermit crabs (Anomura,Paguroidea) are described from thesouthern Pyrenean basins (Huesca,NE Spain). Parapetrochirus nov. withP. robustus n. gen., n. sp., as type species,comes from the lower Eocene(Ypresian) Roda Formation. It preservesboth chelipeds exhibiting anotable heterochely, a larger left chelipedand a concavity without granulationin the inner upper portions.Eocalcinus gerardbretoni n. sp. comesfrom the highest levels of the ArguisFormation (Priabonian) in Yestelocality. This species is characterizedby a hemispherical outline and asinuous lower margin of the chela,which differs from the type species ofthe genus. The cheliped morphologyof such species allows inclusion in thefamilies Diogenidae and Calcinidae,respectively. Fossil paguroids are relativelyrare in the Eocene of Spain,therefore, the description of thesetwo new taxa increases the knowndiversity of this group. Parapetrochirusrobustus n. gen., n. sp. inhabited siliciclasticsubstrates within a prodeltaenvironment and E. gerardbretoni n.sp. was collected from the last levelsof coral rudstones just below thecontinental influence of Yeste-ArrésFormation