Alpinacris tumidicauda is a species of grasshopper only known from Otago and Southland, New Zealand. The genus Alpinacris is endemic to the South Island of New Zealand. A. tumidicauda was described in 1967 by Robert Sidney Bigelow, with a type locality of Obelisk in the Old Man Range A male holotype and paratype are deposited in the Canterbury Museum, Christchurch. Like all of New Zealand sub-alpine and alpine grasshoppers, A. tumidicauda has a 2- or 3-year life cycle. The eggs must "overwinter" before they will hatch. Hoppers are found throughout the year, and adult grasshoppers can be found throughout the New Zealand summer between December and April. The adult A. tumidicauda do not overwinter.
Alpinacris tumidicauda is known only from the Otago and Southland regions of New Zealand.[1] It can be found as far south as Cleughearn Peak and as far north as Mount Aurum Alpinacris tumidicauda prefers alpine tussock grasslands between 1300mand1700mm (4,300feetand5,600feetm); it can, however, be found as low as 700m (2,300feet) near the Nevis River It is one of three known species of alpine grasshoppers that are found in Fiordland, the other two being Sigaus homerensis and Sigaus takahe.[2]
Alpinacris tumidicauda has a "sister species", Alpinacris crassicauda. There would have originally been only one species of Alpinacris in the South Island; however, the Alpine Fault has separated this species over time, so at the present there are two species—A. tumidicauda in southeast of the South Island and A. crassicauda in the northwest of the island.[3] [4]
Alpinacris tumidicauda is micropterous (small-winged), with wings measuring between 2mm4mm, making this species flightless like most New Zealand grasshoppers. Male body length is 12mm14mm; female body length is 21mm24mm.
Four colour morphs are known for adult A. tumidicauda: green, olive, dark olive and yellow-brown. The most common colour morph is green, followed by the yellow-brown colour morph.