Orocrambus sophistes (Meyrick, 1905)
Orocrambus sophistes (Meyrick, 1905)
Current DoC threat status
Nationally Vulnerable.Recognition / similar species
Similar to Orocrambus cyclopicus but larger and with a short-winged female (female O. cyclopicus fully winged). In well-marked specimens with a transverse dark streak across the forewing from before the middle of the dorsum (trailing edge), this streak is very oblique in O. sophistes, but more nearly at right angles to the dorsum in O. cyclopicus.
Known distribution and abundance
The species is widespread but very localised in the inland valley-floors and adjacent low alpine areas of the southern South Island, in Central Otago and the Mackenzie Basin. The flightless female of the species severely limits dispersal.
Habitat
Montane to low alpine short-tussock grassland of Festuca novae-zelandiae and Carex muelleri.
Host-plant and biology of early stages
Not known but suspected to have larvae feeding on the short tussock Festuca novae-zelandiae as short-winged females have been found sitting on this grass at night.
Flight period (months of year) and behaviour of adult
Adults found from mid January to April but most common mid February to early March. Adult males can easily be disturbed by day but the species comes readily to light indicating it is a nocturnal species.
Potential monitoring technique(s)
Standardised light trapping is an excellent method to determine the changing population of the species as the males come readily to ultra-violet light.
Threats
Generally the species is found on the extensively grazed Pastoral Leases of the inland South Island. Ongoing degradation of the short tussock grassland habitat through intensification and conversion is a threat, with the valley floors being particularly vulnerable. Protection and appropriate management of large areas of the inland South Island’s short tussock grasslands is required. But as time goes on fewer opportunities are available to secure suitable habitat for long-term conservation of this species.