The Kermedecs – at the meeting point between the tropical waters of the Pacific and New Zealand’s temperate seas – is a unique environment that hosts a unique mix of species. The region’s decapod (crustacean) population is no exception. Altogether, 88 species of crustacean are known here, including tropical and temperate species of crayfish, crabs, prawns and shrimps. At present, 17 decapod species are known only in the Kermadec region. It is also significant as the only locality within New Zealand waters at which 57 decapod species occur, including several that are new to science.
Some of these species are specialised for Kermadec habitats. For example, hydrothermal vents on the Kermadec Arc are the habitat of the ‘vent crabs’ Gandalfus puia and Xenograpsus ngatama. These crabs have adapted to survive one of the harshest environments imaginable including searing temperatures, high acidity and potentially toxic chemicals.