A striped gecko (Hoplodactylus stephensi) at Coromandel

The striped gecko (Hoplodactylus stephensi Robb 1980) is one of the rarest and most restricted of the New Zealand lizards. Until now it has been found only on Stephens Island in western Cook Strait and Maud Island in Pelorus Sound. The species is strongly nocturnal and primarily arboreal, inhabiting shrublands and forest remnants. In March 1997 an unusual and distinctive gecko was found in a house on the outskirts of Coromandel township on the western side of the Coromandel Peninsula. Morphometric and genetic data (DNA) from this gecko showed that it is conspecific with Hoplodactylus stephensi from the Cook Strait region. Minor differences between the mitochondrial DNA sequences of the Coromandel animal and those from Cook Strait indicate that the Coromandel animal is almost certainly from a distinctive-and hitherto undiscoveredpopulation of striped geckos that is natural to the area. Follow-up surveys using a variety of techniques (pit-trapping, spot-lighting and artificial cover) have thus far failed to locate further specimens. Interpretation of the minor genetic and morphological differences that were observed between the Coromandel gecko and striped geckos from the Cook Strait region is limited by the very small sample sizes, and at this stage further taxonomic differentiation of the Coromandel population is not warranted. Coromandel is 460 km north of the Cook Strait populations of striped geckos and at the opposite end of the North Island. The habitat they presently occupy (seral manuka-kanuka forest) is novel, but the former lowland forest of the Coromandel region is structurally and floristically similar to that at the Cook Strait sites. This indicates striped geckos were probably distributed through lowland forest in the central and southern North Island, and parts of the northern South Island, and that they may still occur at other sites within this range. Striped geckos appear to be rare and/or elusive, or their primary habitat is yet to be identified. The new population of striped geckos is exposed to a broad range of introduced mammalian predators and its habitat is not secure from clearance or modification. These factors mean the conservation status of the species is essentially unchanged and the present DOC conservation priority ranking (Category B, Vulnerable) and the IUCN 'Red List ' classification should remain. Because it represents the northern limit of the species' range and is morphological and genetically distinct, the Coromandel population warrants special conservation consideration.