Cantuaria magna is a species of trapdoor spider endemic to New Zealand.

[1] This species was described in 1968 by Ray Forster from male and female specimens collected in Westland.

The abdomen is dark brown with a pale area dorsally.

The female is coloured like the male, but has extra pale areas on the abdomen.

[2] This article related to mygalomorph spiders is a stub.