A revision of the genus Prionocrangon (Crustacea: Decapoda: Caridea: Crangonidae)

Abstract

Additional specimens belonging to the rare crangonid genus Prionocrangon Wood‐Mason and Alcock, 1891 collected from recent deep‐sea expeditions in the West Pacific enable a revision of this poorly known genus. The four previously described species are all valid. The type species P. ommatosteres Wood‐Mason and Alcock, 1891, originally known only from the Andaman Sea, is considered to be also distributed in the Philippines and Indonesia. However, the material previously assigned to “P. ommatosteres” by de Man (1920) and Chace (1984) from Indonesia and the Philippines actually represents a new species, P. demani sp. nov., close to P. pectinata Faxon, 1896. Prionocrangon pectinata and P. curvicaulis Yaldwyn, 1960 are still only known by their types. The distribution of P. dofleini Balss, 1913 is now extended from Japan to Taiwan. Two more new species are recognized. Prionocrangon formosa sp. nov. from Taiwan is closely related to P. curvicaulis while P. paucispina sp. nov. from Taiwan and New Caledonia is unique in having very few dorsal carapace spines. The genus Prionocrangon is newly diagnosed and a key to the species is provided. Nevertheless, a damaged specimen from the Sulu Sea could not be satisfactorily assigned to any of the above seven species, suggesting that this genus may have even higher diversity.