Gobsmacking goby fish species found in museums

An exquisite new species of goby has just been described – and it was found in a museum! A new publication co-authored by Dr Yi-Kai Tea, the Australian Museum’s Chadwick Biodiversity Research Fellow, describes these showstopping fishes and highlights the importance of taxonomic research in museums.

Describing a species new to science is certainly an exciting endeavour but what many may not realise is that scientists sometimes describe a new species without collecting any new material. This was the case in the newly published study by the Australian Museum’s Chadwick Biodiversity Research Fellow Dr Yi-Kai Tea, and Dr Helen Larson. The authors revised the taxonomy of a species of dartfish belonging to the goby genus Nemateleotris. The species, Nemateleotris helfrichi, is one of only four in this genus. They soon realised however that what was known as N. helfrichi was actually two species of fishes that differed in aspects of colouration, size, and geographical distribution. What is more interesting is that the study was borne entirely out of examining existing specimens housed in museums.

Careful examination of material housed in museums all over the world and comparison of live underwater photographs revealed the presence of two distinct species living in non-overlapping parts of the world. Nemateleotris helfrichi is restricted to the islands of French Polynesia, and the newly described species N. lavandula, occurs elsewhere in the western and central Pacific. Both species are most easily separated in colouration details of the head and snout. Notably, the “moustached” N. helfrichi has a distinct black mark on its upper jaw, which is absent in N. lavandula.

Strangely, for a fish that is so widespread and popular as an aquarium pet, it is very poorly represented in museums. The new species is described based on only thirteen specimens which are scattered across museums in Australia, the United States, Japan, and Singapore. The holotype was selected from a specimen housed right here at the Australian Museum, and is extra special because it now holds two type statuses, the other being the paratype of N. helfrichi.

The description of the new species accompanies a revision of the genus Nemateleotris, with new accounts of osteology, re-diagnosis of all species, and a revised key to species. This study by Kai and Helen is an excellent example of how revisiting historical taxonomic descriptions with fresh eyes can have a direct impact on conservation and species management. In this case, one species, previously thought to be widespread, has been found to harbour cryptic diversity, leading to the understanding that the newly described species is restricted to a much smaller distribution than previously known.