Landcare Research - Manaaki Whenua

Landcare-Research -Manaaki Whenua

Ochlerotatus (Ochlerotatus) vigilax (Skuse, 1850)

New Zealand Status: Not Present

Ochlerotatus vigilax is moderately invasive having moved from South East Asia and Australia into the southwestern Pacific. It is a moderate biosecurity threat because it could probably survive in New Zealand and transmit disease. It has a propensity to disperse and be windblown for many kilometres (Russell 1993).

Vector and Disease Information

Ochlerotatus vigilax is a major coastal pest for the New South Wales and South Australia regions as well as more northern areas, and it is the major vector of Ross River virus in coastal NSW (Russell 1993). Ochlerotatus vigilax is recognised as a major vector of Ross River (RR) and Barmah Forest (BF) viruses in the Moreton Bay islands in Queensland (Jeffery et al. 2002). However, it appears to be a less efficient vector of Japanese encephalitis virus (JE). Specimens collected from far north Queensland had a laboratory infection rate of greater than 55%, but only 17% were able to transmit the virus (Hurk et al. 2003). A single isolate of Kokobera virus (KOK) was obtained from Ochlerotatus vigilax on Western Cape York Peninsula, Australia (Johansen et al. 2003).

Distribution (based on Biogeographic Regions)

Australasian Biogeographic Region

New Zealand

Not present, intercepted

Intercepted in 2002 (Gilbert 2002), USA - Hawaii (Lee et al. 1984).

Australia

Present, endemic

(New South Wales, Northern Territory, Queensland, South Australia, Victoria, Western Australia) (Lee et al. 1984), Indonesia (Irian Jaya), Papua New Guinea (Bismarck Archipelago).

New Caledonia (including Îles des Pins, Loyalty Islands) (Laird 1954), Fiji (Laird 1956), Solomon Islands (Guadalcanal Island) (Laird 1956), Vanuatu (Laird 1956).

Present, introduced

Oriental Biogeographic Region

Indonesia (Java, Lesser Sunda Islands, Sulawesi, Timor) (WRBU 2001), Japan (Ryukyu Archipelago, Yaeyama Islands) (Tanaka et al. 1979), Malaysian Peninsula, Philippines, Taiwan, Thailand, Vietnam (WRBU 2001).

Present, endemic

Afrotropical Biogeographic Region

Seychelles (WRBU 2001)

Present, endemic?

Rest of the World

Not present

Taxonomic Position

This species is placed in Section vigilax of the subgenus Ochlerotatus, which includes antipodeus and 3 other species from the South Pacific.

Diagnosis

A diagnosis is the minimum set of characters and states that will separate this taxon from all others in this set of taxa.

Diagnostic characters State
Postspiracular setae Present
Pale scales of proboscis Forming a band around proboscis
Decumbent scales on the vertex Mostly narrow, scale width uniform

Characteristic Features

A medium-sized dark mosquito. Thorax: scutum with dark bronzy and golden scales. Wings: dark scaled with some pale scales on front veins. Legs: with bands of pale scales (Russell 1993).