Electrophoretic evidence for the presence of Tandanus tandanus (Pisces: Plotosidae) immediately north and south of the Hunter River, New South Wales

Eel-tailed catfish from the genus Tandanus are morphologically conservative. Previous allozyme electrophoretic surveys have demonstrated that up to three species of Tandanus catfish occur in south-eastern Australian freshwater streams. Two of these species are previously undescribed cryptic species. However, the taxonomic status of catfish in many coastal river systems is yet to be examined using allozyme electrophoresis. In this study four diagnostic allozyme markers were used to determine the taxonomic status of eel-tailed catfish in four NSW coastal populations from the Wallamba, Coolongolook, Hawkesbury and Georges River systems. Electrophoretic analyses demonstrated that the species of catfish in these four populations is T. tandanus. These results extend the distribution of T. tandanus to the coastal rivers immediately north and south of the Hunter River, NSW