Parioglossus (Teleostei: Gobioidei: Microdesmidae) in New Zealand

Abstract

The genus Parioglossus is known widely across the Indo‐West Pacific from tropical western Pacific islands (Fiji, Vanuatu, New Caledonia), through eastern subtropical to tropical Australia, in south‐east Asia and north to Japan, and west across the Indian Ocean to Madagascar. It is hitherto not recorded from New Zealand, but is here reported from a stream near North Cape in far northern New Zealand, and another draining a wetland on Great Barrier Island in the north‐east of the country. New Zealand specimens do not conform completely to any published descriptions of Parioglossus, but this seems likely to reflect inadequacies in the published descriptions. The fish appear closest to the eastern Australian P. marginalis. Typical habitat is unclear, though simple testing of euryhalinity suggests an ability to inhabit marine, brackish, and possibly fresh waters. Whether the species has been long present in New Zealand waters, undiscovered, has dispersed to New Zealand across the Tasman Sea in ocean currents, or was brought to New Zealand in ballast water discharged from ships, is not known. Parioglossus is one of several species newly discovered in New Zealand waters, for which various explanations are possible.