A review of Lyocyclidae Thiele, 1925 (Gastropoda: Caenogastropoda) from the Indo-Pacific, with the description of one new genus and twenty-eight new species

Twenty-eight new upper-bathyal benthic species in Lyocyclidae (Caenogastropoda) from the Indo-Pacific are described, of which twenty-seven new species are assigned to the genus Lyocyclus Thiele, 1925 and one more in the new genus Nescitus n. gen, herein described. All species are illustrated by SEM micrographs and compared with the previously known ones. Photographs of the species described by THIELE (1925) from the Indian Ocean are provided for the first time. Lyocyclus biconcavus Thiele, 1925 is here assigned to the genus Eudaronia Cotton, 1945 and Lyocyclus orientalis Thiele, 1925 to the genus Adeuomphalus Seguenza, 1876, both in the Seguenzioidea superfamily