AbstractThe genus Hypoderma is redefined, based primarily on features associated with ascomatal development, rather than on ascospore shape. Twelve species are reported from New Zealand of which eleven are described as new: H. alborubrum, H. bidwillii, H. bihospitum, H. campanulatum, H. carinatum, H. cookianum, H. cordylines, H. dundasicum, H. obtectum, H. sigmoideum, and H. sticheri. H. rubi is newly recorded. In addition to descriptions and illustrations of all species, dichotomous and multiple entry keys, and a table summarising host plant distributions, are provided.