The New Zealand triplefin Grahamina signata (Teleostei: Tripterygiidae): A junior synonym of G.gymnota from Tasmania

Abstract

The tripterygiid fish Grahamina signata Fricke & Roberts, 1993 was described from 174 specimens collected from several exposed locations around the coast of New Zealand. It was distinguished from the Tasmanian G. gymnota (Scott 1977) by the number of pored scales in the lower lateral line, the number of branches of the supraorbital tentacle, and the colouration of the pectoral-fin base. Examination of new material of G. signata from the Auckland region, and re-examination of type material of G. gymnota, show that the supraorbital tentacle and lower lateral line are not differences of taxonomic significance. Pectoral fin colouration in a published underwater photo of G. gymnota suggests that the colour difference was due to the effects of preservation. We therefore refer G. signata to the synonymy of G. gymnota. This synonymy, in combination with the restricted Tasmanian distribution and dispersal capabilities of the species, suggests that G. gymnota was introduced to Tasmania from New Zealand.