A new species of the genus Linuparus (Crustacea, Palinuridae) from South-East Africa

INTRODUCTION The genus Linuparus White was recently reviewed by Bruce (1965) who gave an excellent account of two species, the type species L. trigonus (Von Siebold) and a previously undescribed species L. sordidus Bruce from the South China Sea. George & Main (1967) reviewed the family Palinuridae and suspected that "four geographically isolated species are probably represented within the recorded distribution of Linuparus; one in Japan (trigonus), one in South China sea (sordidus), one off Portuguese East Africa. .. and one off east Australia...". During 1970, when one of us (R.W.G.) visited the Oceanographic Research Institute at Durban, the opportunity was taken by us to assemble relevant specimens of Linuparus for comparison and review of that suspicion. On the basis of the examined material, three species of the genus Linuparus are recognised: L. trigonus (Von Siebold, 1824) in the western Pacific from Japan, South China Sea, Philippines and eastern Australia (81 to 313 m), L. sordidus Bruce, 1965, from South China Sea to northwestern Australia (310 to 328 m) and L. somniosus sp. nov. in the western Indian Ocean from Moçambique to Natal (216 to 320 m). The three species can be distinguished with the help of the following key: 1. Submarginal posterior groove of carapace as wide medially as laterally. No pleopods on first abdominal segment of female............2 — Submarginal posterior groove of carapace much wider medially than laterally. Vestigial pleopods present on first abdominal segment of female...... .................L. somniosus sp. nov. 2. Epistomal ridges coarsely granulated, without an acute well developed anterior tooth.