Five monotypic genera of Rhaphidophoridae have been described from remote islands located south and east of New Zealand's South Island and surrounded by ocean for at least 100 km in all directions. These genera are Novoplectron Richards, 1958 from Chatham Islands; Ischyroplectron Hutton, 1896 from Bounty Islands; Notoplectron Richards, 1964 from Campbell Island; Dendroplectron Richards, 1964 from Auckland Islands; and Insulanoplectron Richards, 1970 from Snares Islands. It is only recently that one of these genera, Notoplectron , was shown to include a species previously described from mainland New Zealand, Notoplectron brewsterense (Richards, 1972). Here, we discuss the discovery of a new species of cave wētā on Rakiura/Stewart Island. Morphology and mitochondrial DNA show that the species is related to Insulanoplectron spinosum Richards, 1970. We thus describe the new species Insulanoplectron stanneum sp. nov. and redescribe the genus Insulanoplectron based on traits that are common to both species.
Hegg et al. (2026) studied this question.