Sigaus homerensis


Sigaus homerensis is a grasshopper endemic to the southern South Island of New Zealand. It is known only from three isolated populations in Fiordland.

Distribution and habitat

The distribution of S. homerensis is not known to overlap with that of any other grasshopper species and it is known only from the Earl Mountains. S. homerensis is one of three known alpine grasshoppers found in Fiordland, the other species being Alpinacris tumidicauda and Sigaus takahe.
Known sites of S. homerensis are regularly swept clear of tall plants by avalanches, making these areas more sparsely vegetated than the surrounding. Similar terrain and vegetation is found outside the known distribution, however, S. homerensis are not found in these areas. A possible explanation of this could be associated with avalanches, vegetation height and sunshine hours. This region receives high rainfall coupled with the lowest sunshine hours in New Zealand. It appears that these small cleared areas are better for S. homerensis than avalanche-free areas with their taller vegetation. New Zealand Acrididae are diurnal sun-baskers and require basking surface to become active for the day. S. homerensis prefer altitudes between, however, it can be found as low as and as high as.

Species description

The wings on S. homerensis are micropterous between making this species flightless like most of New Zealand grasshoppers. Male body length ; Female body length.

Type information

Polymorphism

Two colour morphs are known for adults S. homerensis, 'Drab gold' and 'Dark blue-grey'. Approximately two-thirds of the adults S. homerensis are of the 'Drab Gold' colour morph.