Redescription of Gobius cauerensis (Bleeker, 1853), with discussion of the validity of the species

Thacker (2004b) regarded the gobiid fish Gnatholepis cauerensis (Bleeker) as a synonym of Gnatholepis anjerensis (Bleeker) and treated G. scapulostigma Herre as the replacement name for what other recent authors had identified as G. cauerensis. The holotype of Gobius cauerensis Bleeker from the Nationaal Natuurhistorische Museum in Leiden is redescribed. Because its colour pattern has faded, the original Bleeker painting is reproduced, the diagnostic colour features noted, and comparison provided with an underwater photograph taken of a specimen before it was collected in the Mentawai Islands (near the type locality of Kauer, Sumatra). Gnatholepis cauerensis is a valid species distinct from G. anjerensis. G. scapulostigma Herre is returned to the synonymy of G. cauerensis. G. thompsoni Jordan from the Atlantic is also a synonym of cauerensis, following Rocha et al. (2005). The validity of G. knighti Jordan & Evermann from the Hawaiian Islands, with records for the Cook Islands and Society Islands, is questioned.