Spiders from Tawhiti Rahi, Poor Knights Islands, New Zealand

Abstract

Forty-three spider species were collected on Tawhiti Rahi: three mygalomorphs —Migas (Migidae), Aparua and Porrhothele (Dipluridae) — and 40 araneomorphs belonging to 34 genera in 20 families. Only two species had previously been reported. While most species are known from the mainland, five genera have one species each that seems to be a distinct Poor Knights form or to have an affinity with more northern populations. The island displays two striking phenomena. None of the adventive spider species common on the mainland was found on Tawhiti Rahi; and the summit plateau supports strikingly large numbers of Porrhothele and Cambridgea living amongst the extensive Poor Knights Islands lily (Xerorzema callistemon) community. © 1982 Journal of the Royal Society if New Zealand.