Isoplectron cochleatum is very similar in size and habitat requirements to its close relative I. armatum. It is found in the very north of the South Island from Farewell Spit to Marlborough Sounds and then in the environs of Wellington. Its known sites are few and all specimens have been taken in regenerating manuka-kanuka shrubland or forest. Like Isoplectron armatum it is prevalent under the dry loose bark especially of kanuka.