Redescription of the colorful deep-water shrimp Lebbeus compressus Holthuis, 1947 and description of a closely allied new species from Taiwan (Decapoda: Caridea: Thoridae)

Abstract

Lebbeus compressus Holthuis, 1947, one of the five peculiar "crested species" of the thorid shrimp genus Lebbeus White, 1847, has been considered to be endemic to Japan. This species inhabits deep waters but has an attractive coloration. Examination of four specimens from northeastern Taiwan, which are morphologically similar to L. compressus, led to the examination of the Japanese material, including topotypic specimens from off Fukushima Prefecture. Lebbeus compressus is redescribed in detail to fully document its specific identity and diagnostic details. A new species, Lebbeus altus sp. nov., is described and illustrated for the Taiwan specimens. The new species differs from L. compressus by the less produced posterior margin of the ter guru of the pleomere 3, the relatively large cornea, fewer accessory spiniform setae on the dactyli of the pereopods 3, and in coloration. Genetic analysis using the barcoding gene mitochondrial COI also supports the recognition of the new species. A key to the six "crested" species of Lebbeus is provided.