Phaulacridium marginale

Phaulacridium marginale
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Orthoptera
Family:	Acrididae
Genus:	Phaulacridium
Species:	P. marginale
Binomial name
Phaulacridium marginale (Walker, 1870)
The distribution of P. marginale in New Zealand

Phaulacridium marginale is an endemic New Zealand grasshopper found in low altitudes throughout the North Island, the South Island, Stewart Island and on many smaller islands.^[1]

Distribution and habitat

The New Zealand P. marginale is commonly found on sand dunes above the high-tide mark, along open grassy river flats and in the sub-alpine zone to an altitude of 1,350 metres (4,430 ft) on the Ragged Range (43°14′47″S 171°06′10″E / 43.246436°S 171.102778°E). It is found only very rarely in exotic grasslands or in built-up areas.

Species description

The wings on P. marginale are micropterous (small wings) between 1–3 millimetres (0.039–0.118 in) making this species flightless like most of New Zealand grasshoppers. However, fully winged adults (89% adults female and 11% adults male^[2]) are extremely rare and can be found throughout New Zealand. As yet no macropterous P. otagoense have been recorded. The obvious benefits of having macropterous wings is to increase survivability by escaping adverse local conditions, colonizing new areas and a more effective way to escape predators. It is not clear what causes the micropterous P. marginale to produce fully develop wings in New Zealand. A possible trigger for this could be if individuals are put under a large amount of stress from harmful local conditions during its final instar.

Male body length 10–15 millimetres (0.39–0.59 in); Female body length 20–30 millimetres (0.79–1.18 in).

Genus

There are five known species of Phaulacridium. Two species Phaulacridium crassum and Phaulacridium vittatum are endemic to the Australian mainland and Phaulacridium howeanum occurs only on Lord Howe Island. Of the two New Zealand Phaulacridium grasshoppers, Phaulacridium otagoense is endemic to the South Island (Mackenzie Basin and Central Otago).

References

1. "New Zealand Grasshopper". Landcare Research. Retrieved 5/3/2013. Check date values in: |access-date= (help)
2. Base on the 34 specimens in the Canterbury Museum, Christchurch; Otago Museum, Dunedin and Private collections.