Hairworms (Nematomorpha: Gordioidea) Infecting New Zealand Short-Horned Grasshoppers (Orthoptera: Acrididae)

A total of 282 short-horned grasshoppers (Acrididae) was collected in a mountainous area of New Zealand's South Island and examined for hairworm (Nematomorpha) infections. Thirteen percent of female Sigaus obelisci and 3% of female S. australis harbored hairworms; males of both species, as well as male and female S. campestris, were all uninfected. All hairworms recovered belong to the species Euchordodes nigromaculatus, previously known only from wetas (Orthoptera: Stenopelmatidae). No size differences were observed between infected and uninfected grasshoppers, and there was no relationship between host size and worm length. This is the first substantiated report of nematomorphs in grasshoppers in New Zealand.