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Snell—New identification keys New ZealandZealand Journal mosquito of Zoology, 2005, Vol. 32: 99–110 0301–4223/05/3202–0099 © The Royal Society of New Zealand 2005

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Identification keys to larval and adult female mosquitoes (Diptera: Culicidae) of New Zealand AMY E. SNELL Ecology and Health Research Centre Department of Public Health Wellington School of Medicine and Health Sciences University of Otago P.O. Box 7343 Wellington South, New Zealand [email protected] Abstract Keys are presented for the identification of larval and adult female life stages of the 12 endemic and four exotic mosquito species known for New Zealand (the keys are to species not genera). The keys include the recent arrival, Ochlerotatus (Ochlerotatus) camptorhynchus (Thomson), and a monotypic genus endemic to New Zealand. A number of Aedine subgenera have been recently raised to genus level (Reinert et al. 2004; Reinert & Harbach 2005) and old and new nomenclature are both given. The keys combine previously scattered information about the current New Zealand mosquito fauna and will assist future biosecurity surveillance and further studies involving mosquitoes as potential arbovirus vectors. Keywords mosquitoes; Culicidae; taxonomy; adults; larvae; New Zealand INTRODUCTION The New Zealand mosquito fauna currently comprises 12 endemic and four exotic species in six genera, one of which is monotypic (Maorigoeldia Edwards, 1902) and restricted to New Zealand. There is no single morphological identification key available

Z04034; Online publication date 13 May 2005 Received 14 September 2004; accepted 20 January 2005

to distinguish larval and adult forms of all species. Usually, the larvae of mosquitoes are more readily identified than adults and existing New Zealand keys are primarily for larvae and do not include all species. Present, taxonomic information is also scattered among a number of publications (refer Materials and Methods below) that are not widely available. This paper combines observations of supplementary taxonomic characteristics (in italics) from museum and field-collected specimens, with existing information from published literature. Field collected specimens examined will be deposited in Te Papa. New Zealand larval and adult mosquitoes can be difficult to distinguish morphologically. In particular, Culiseta (Climacura) tonnoiri (Edwards) and Culiseta (Climacura) novaezealandiae Pillai are very similar, and further research is needed to clarify their relationship (Belkin, 1968). Mosquitoes belonging to the Culex pervigilans species complex (Culex (Culex) pervigilans Bergroth, Culex (Culex) asteliae Belkin and Culex (Culex) rotoruae Belkin) are difficult to distinguish and larva and adult Cx. pervigilans can also be confusing (Belkin, 1968). A number of Aedine subgenera have been recently raised to genus level (Reinert et al. 2004; Reinert & Harbach 2005). Subsequently, old and new nomenclature is given here to provide clarification. Revisions of taxonomic keys published elsewhere have often been a reaction to the interception of exotic species, as was the case following the introduction of Culex (Culex) gelidus Theobald (Whelan et al. 2000) and the interception of Stegomyia albopicta (Skuse) (Aedes albopictus, the Asian tiger mosquito) in the Northern Territory of Australia (Lamche et al. 2003). The ability to correctly distinguish important pest and vector species that might be collected during surveillance operations enables authorities to determine the requirements for control operations, properly implement these operations, and evaluate and improve implementation (Russell 1993). The risk of vector-borne disease has increased in New Zealand with the introduction of the southern salt marsh mosquito, Ochlerotatus (Ochlerotatus) camptorhynchus (Thomson) in 1998 (Hearnden

100 1999). This species is a competent vector of Ross River virus (Ballard & Marshall 1986). In addition, all four naturalised New Zealand species have demonstrated vector competence for arboviruses that cause human illness in other countries (Russell 1995, 1998, 2002; Watson & Kay 1999). Interceptions have been recorded in New Zealand of disease-carrying vectors such as Stegomyia aegypti (Linnaeus) (Aedes aegypti) (Ministry of Health 2001, 2004), St. albopicta (Laird et al. 1994), Ochlerotatus (Finlaya) japonicus (Theobald) (Ministry of Health 2002, 2003b), Cx. gelidus (Ministry of Health 2003a) and Stegomyia polynesiensis (Marks) (Aedes polynesiensis) (Ministry of Health 2004). These mosquitoes could pose threats to public health if they were to become established and encounter viraemic humans. At present, New Zealand has no vector-borne diseases that cause human illness (Weinstein et al. 1995), but there is an increased risk of these diseases entering the country both by accidental introduction of a mosquito species carrying a disease or by a viraemic or disease-carrying human who could then be bitten by local mosquitoes. The number of vector-borne disease case notifications in New Zealand has been steadily increasing over the last decade based on the number of cases of dengue fever and malaria (Institute of Environmental Science and Limited Research 2004). This is combined with increases in migration to New Zealand, and incoming tourists and returning residents. To be effective, control measures implemented against any vector mosquito must be based on its biology, which cannot be known until its identification is confirmed (Rogers 1974). Correct identification of mosquito species is essential to the health risk assessment process, and the adult and larval keys presented herewith will be valuable tools for biosecurity surveillance because they can be used accurately and quickly to distinguish endemic and naturalised species from exotic species that are intercepted in the vicinity of air and shipping points. MATERIALS AND METHODS Specimens from several sources were examined. Field collections were made during 2001–03 from the Waitakere Ranges (Auckland), Hooper’s Inlet (Dunedin), Kuirau Park (Rotorua), Nga Manu Nature Reserve (Waikanae), Kaipara Harbour (Northland), Karori Wildlife Sanctuary (Wellington), Whataroa (West Coast, South Island), Island Bay (Wellington);

New Zealand Journal of Zoology, 2005, Vol. 32 also preserved specimens from Auckland Museum, Te Papa (Museum of New Zealand Te Papa Tongarewa) and the New Zealand Arthropod Collection (NZAC, Auckland). Taxonomic descriptions were also examined from the literature, i.e., Edwards (1920, 1924, 1925); Miller (1922); Cooling (1924); Graham (1929, 1939); Wood (1929); Miller & Phillips (1952); Klein & Marks (1960); Belkin (1962, 1968); Dumbleton (1962, 1965, 1968); Nye (1962); Marks & Nye (1963); Nye & McGregor (1964); Dobrotworsky (1965); Pillai (1966a,b, 1968); Lee et al. (1982, 1984, 1988, 1988a,b, 1989); Marks (1982); Liehne (1991); Russell (1993); Weinstein et al. (1997); and Winterbourn et al. (2000). For morphological terms refer to Fig. 1–12. More commonly used morphological terminology has been used in these keys and where possible has been defined according to the nomenclature of Harbach & Knight (1980). PRESERVATION OF MOSQUITO SPECIMENS To ensure that specimens are in optimal conditions for use with the keys, larger larval instars (3rd or 4th) should be used, as diagnostic features are not always developed in 1st and 2nd instars. Larvae should first be killed in hot water just below boiling point to denature enzymes and fix the proteins. This prevents the specimens from curling up and later darkening (Upton 1991). Specimens should then be placed in 75% ethanol (Walker & Crosby 1988). The key can be used with dry and freshly caught adult female specimens. However, it may not be possible to identify damaged specimens if particular characters are not present, e.g., scales have been rubbed off or hind legs are not present (Russell 1993). Adults should be killed by placing in the freezer overnight or on dry ice in a container. The method of killing and storage must be appropriate for the purpose of their collection (e.g., for virus isolation). Specimens for identification should be thawed before being handled to ensure appendages are not knocked off (Upton 1991). The best specimens should either be pinned or stored correctly to minimise any damage (refer to Walker & Crosby (1988) for procedures). The preservation of mosquito adults in ethanol for identification (unless required) is not recommended as this often discolours and dislodges scales. Specimens stored in ethanol must be kept away from light to avoid bleaching (Walker & Crosby 1988).

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Fig. 1–2 1, The terminal segments of a generalised mosquito larva. 2, Generalised terminal segments of Anopheles spp.

IDENTIFICATION KEY TO THE FOURTH INSTAR LARVAE OF MOSQUITOES IN (Fig. 1–6) NEW ZEALAND 1.

–Larvae with siphon (breathing tube) at posterior end (Fig. 1) .....................................................2 –Larvae with no siphon at posterior end (Fig. 2) ........................................... ..Anopheles Meigen (Anopheles spp. are not currently present in New Zealand, but are abundant in neighbouring countries) 2 (1) –Siphon with normal spiracular apparatus at tip (Fig. 1) ..............................................................3 –Siphon with spiracular apparatus modified with a saw-like apparatus for piercing plant tissue (Fig. 3) ........................................................................................................... Coquillettidia Dyar Larvae of the two Coquillettidia species from New Zealand, Cq. iracunda (Walker) and Cq. tenuipalpis (Edwards) are undescribed. Only pupae and pupal exuviae are known for these species (Belkin 1968). 3 (2) –Siphon with more than 1 pair of ventro-lateral hair tufts (setae 1a-S, 1b-S etc; Fig. 4) ..............7 –Siphon with only 1 pair of ventro-lateral hair tufts (seta 1-S) either at extreme base (Fig. 5) or mid length .............................................................................................................................................. 4 4 (3) –Siphon with very small ventro-lateral tuft only at extreme base, lateral comb scales in a single row, minute single or bifid tufts distributed along the length of the siphon (Fig. 5) ...................5 –Siphon with ventro-lateral hair tuft (seta 1-S) about or beyond mid length of siphon, without comb scales in a single row and minute tufts ..............................................................................6 5 (4) –Lateral comb with 18–20 comb scales1, anal papillae constricted between one-third and one half length from base of the saddle .................................. ..Culiseta (Climacura) tonnoiri (Edwards) –Lateral comb with 25–29 comb scales1, anal papillae not constricted .......................................... .............................................................................. Culiseta (Climacura) novaezealandiae Pillai 6 (4) –Siphon with more than 3 pecten teeth (Fig. 1) ...........................................................................11 –Siphon with 2–3 pecten teeth spaced widely apart (lateral comb in a triangular patch of 70 or more scales; anal papillae short and rounded, subequal in length) ............................................... .................................................................................................. Opifex (Opifex) fuscus (Hutton) 7 (3) –Siphon with 4–7 pairs of ventro-lateral hair tufts ........................................................................8 –Siphon with 9–11 pairs of long ventro-lateral hair tufts (also with 9–11 dorso-lateral hair tufts; 4–6 pecten teeth; lateral comb a large patch with >80 scales; anal papillae longer than saddle and rounded apically) ....................................................................Maorigoeldia argyropus (Walker) (continued)

102 8 (7)

9 (8)

10 (9)

11 (6) 12 (11)

13 (11)

14 (13)

15 (14)

New Zealand Journal of Zoology, 2005, Vol. 32 –Siphon with 4 pairs of ventro-lateral hair tufts ............................................................................9 –Siphon with 5 (rarely with 4, 6, or 7) pairs of ventro-lateral hair tufts (setae 1a-S to 1e-S)2 in alignment with pecten teeth (siphon with 6–9 small pecten teeth; lateral comb a patch of 30–40 scales; anal papillae short and pointed, usually subequal to saddle length or shorter; distribution restricted to the North Island, collected from thermal pools and their outflows in the Rotorua area, and Kaikohe)................................................................................Culex (Culex) rotoruae Belkin –Siphon with a siphon index of <8.53, with four pairs of hair tufts either ventro-lateral or dorsolateral with 1 pair out of alignment ...........................................................................................10 –Siphon long, with a siphon index of >8.53, siphon with 4 pairs of ventro-lateral hair tufts, and 2 pairs out of alignment with pecten teeth (seta 1b-S and 1c-S) (pecten teeth small, usually less than 10; lateral comb a patch of 30–40 scales; anal papillae subequal, shorter than saddle and pointed) ........................................................................................ .Culex (Culex) asteliae Belkin –Siphon with 4 pairs of ventro-lateral hair tufts, with seta 1c-S out of alignment with pecten teeth; siphon straight; anal papillae subequal, longer than saddle; usually with 12 (9–15) pecten teeth; lateral comb a patch of 40–48 scales (variation between individuals has been observed, sometimes with more than one hair out of alignment or with more than 4 pairs of ventro-lateral hair tufts, usually 5 or 6 as in Fig. 4) ................................................... Culex (Culex) pervigilans Bergroth –Siphon with 4 pairs of ventro-lateral hair tufts with seta 1d-S out of line with pecten (seta 1a-S usually above level of pecten teeth); siphon with distinct bulge in lower half to middle; with 8–12 pecten teeth; lateral comb a patch of 30–40 scales; anal papillae long and pointed about length of the saddle, dorsal anal papillae longer than ventral anal papillae ............................................. ........................................................................................... Culex (Culex) quinquefasciatus Say –Head hair 5 and 6 both single (Fig. 6) .......................................................................................12 –Head hair 5 with 2–4 branches, head hair 6 with 1–3 branches (Fig. 6) ...................................13 –Anal papillae unequal, with dorsal pair as long as saddle and longer than ventral pair; lateral comb in a patch of 20–30 fringed scales; siphon usually with 15–19 pecten teeth extending just beyond mid point ............................................................. ..Ochlerotatus (Finlaya) notoscriptus (Skuse) –Anal papillae small and globular; lateral comb in a large patch of 100 or more scales; pecten with two types of teeth, those at base short and widely spaced, followed by 10–15 long teeth............ ...............................................................Halaedes australis (Erichson) (Ochlerotatus australis) –Pecten teeth extending in a continuous series, no other teeth nearby ........................................14 –Pecten teeth extending in a continuous series (13–17 teeth), with 1–3 large, darkly pigmented conspicuous widely separated teeth above ventro-lateral hair tuft (head hair 5 and 6 both usually double; lateral comb a patch of 60–100 small scales in about five rows) ..................................... ..................................................... Ochlerotatus (Ochlerotatus) subalbirostris Klein and Marks –Anal papillae small and rounded ...............................................................................................15 –Anal papillae equal in length and pointed, about four-fifths the length of the saddle (head hair 6 usually single, head hair 5 usually triple; lateral comb a patch of 30–45 scales; siphon with 17–22 pecten teeth) ................................................Ochlerotatus (Ochlerotatus) antipodeus (Edwards) –Head hair 6 single, head hair 5 usually double branched (1–3), lateral comb a large patch of 100 minute broad fringed scales; anal papillae small and rounded, dorsal pair almost twice as large as ventral (distribution restricted to the Chatham Islands) ................................................... ......................... Opifex (Nothoskusea) chathamicus (Dumbleton) (Ochlerotatus chathamicus) –Head hair 6 is 2–3 branched, head hair 5 is 3–4 branched; lateral comb a patch of 25–35 fringed scales; anal papillae small and globular about one-fifth the length of the saddle ......................... ......................................................... Ochlerotatus (Ochlerotatus) camptorhynchus (Thomson)

In species where more than one ventro-lateral hair tuft is aligned along the siphon, they are designated as seta 1a-S, seta 1b-S etc, with 1a being the most proximal (Fig. 4). 2 The number of lateral comb scales of these species varies, and more specimens need to be collected and examined to adequately determine the number. 3 Siphon index—the ratio of the siphon length to the siphon width. 1

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Fig. 3–6 3, Generalised terminal segments of Coquillettidia spp. 4, Variation in the arrangement of ventro-lateral hair tufts on the siphon of Culex pervigilans. 5, Generalised drawing of terminal segments of Culiseta spp. showing important features for identification (Redrawn from Belkin 1962, including modifications). 6, Head of mosquito larva (dorsal aspect) showing important features for identification.

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IDENTIFICATION KEY TO FEMALE ADULT MOSQUITOES IN NEW ZEALAND (Fig. 7–12) Average wing length measurements in millimetres (Belkin 1968) are used here as an index of mosquito size (Fig. 7). However, they are given only as a guide, as there is often variation in the size of adult mosquitoes. Variation in size in some mosquito species has been shown to be related to characteristics of larval habitats e.g., temperature, nutrition, and larval density (Clements 2000; Schneider et al. 2004). 1 –Head with palps that are as long or nearly as long as the proboscis .............................Anopheles (Anopheles spp. are not currently present in New Zealand, but are abundant in neighbouring countries) –Head with palps that are no longer than two-thirds the length of the proboscis ......................... 2 2 (1) –Wings with conspicuous, spotted, dark scaling on veins (Fig. 9) (together with a pre-apical pale band on all femora) ..................................................................................................................... .3 –Wings without conspicuous, spotted, dark scaling on veins....................................................... .4 3 (2) –Known from Giant Kauri (Agathis australis) forested areas (North Island) and swampy Kahikatea (Podocarpus dacrycarpus) forested areas (South Island) (see Note below) .... .Culiseta tonnoiri –Known only from its type locality: Tahakopa (South Island), a New Zealand flax (Phormium tenax) swamp at the edge of a coastal broad leaf forest (see Note below) .................................... ............................................................................................................. Culiseta novaezealandiae 4 (2) –Hind legs with pale scaling on tarsi, forming distinct bands or third to fifth tarsus all white scaled (Fig. 10) ..................................................................................................................................... ..5 –Hind legs with no distinct pale bands (although there may be a few pale scales at the tarsal joints) ........................................................................................................................................... 9 5 (4) –Proboscis without distinct pale band or ring about mid length.................................................... 6 –Proboscis with distinct pale band or ring about mid length. (A small to medium-sized mosquito with conspicuous silvery scaling on scutum forming a “lyre” shape, consisting of a pair of curved lateral stripes, a long median line and short, narrow straight stripes on each side of the median line; femur and tibia of hind leg with pale longitudinal stripe, and tarsal segments with basal pale bands; abdominal tergites dark with basal pale patches or constricted bands separated from lateral pale patches) ........................................................................................Ochlerotatus notoscriptus 6 (5) –Femur of hind leg mottled; proboscis either mottled or with extensive pale scaling ................. .7 –Femur of hind leg not mottled; proboscis all dark scaled............................................................ 8 7 (6) –A medium to large mosquito, femur, tibia and first tarsus of hind leg strongly mottled with pale scales, also with pale basal bands on tarsi (2–5); proboscis extensively mottled, particularly on underside; abdominal tergites with pale basal bands often triangular shaped (Fig. 11); sternites pale-scaled with medial dark patches and sometimes apical lateral patches ................................ . ..................................................................................................... Ochlerotatus camptorhynchus –A medium to large mosquito; femur of hind leg mottled with predominantly pale scales, knee spots inconspicuous; tibia with some pale scales at base and apex, tarsi with very narrow pale basal bands; proboscis with slight mottling, with variable amount of pale scaling, usually restricted to basal three quarters; abdominal tergites with narrow pale basal bands merging with basal lateral triangular pale patches; sternites predominantly pale-scaled with apical dark patches (restricted distribution to the south-east of the South Island) ............................ Ochlerotatus subalbirostris 8 (6) –A large mosquito with conspicuous silvery scaling with a bluish tinge on the hind femur in the form of post-medial and pre-apical rings (Fig. 10), and an apical patch on the tibia; hind leg with fifth tarsus all white; proboscis all dark-scaled; palps with some silvery scaling on middle segments; abdominal tergites all dark-scaled; sternites dark-scaled with apical lateral patches of broad silvery scales ................................................................................ Maorigoeldia argyropus –A medium to large mosquito; hind femur with pale scaling on basal half to two-thirds on ventral side, also with an inconspicuous knee spot; tarsi with narrow pale basal bands; remainder of leg all dark-scaled; proboscis and palps all dark-scaled; abdominal tergites dark-scaled with narrow to broad pale basal bands merging with large, pale, basal lateral patches; sternites dark-scaled with basal lateral pale patches ...............................................................Ochlerotatus antipodeus 9 (4) –Tip of abdomen tapering (Fig. 11) ............................................................................................. 10 –Tip of abdomen rounded off or square-ended ........................................................................... 12

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Fig. 7 Mosquito body size range in relation to wing length.

Fig. 8 Generalised adult morphology.

10 (9) –Head with upright scales on vertex (Fig. 8) ............................................................................... 11 –Head without upright scales on vertex. (A medium to large dark mosquito with numerous short, curved hairs on vertex and occiput; first three basal segments of antennae with conspicuous pair of rigid hairs; palps about a quarter the length of the proboscis, with distal segment club-shaped; proboscis all dark scaled and downwardly curved; tergites and sternites sparsely-scaled and with numerous hairs) ...................................................................................................... Opifex fuscus 11 (10) –A medium-sized mosquito, proboscis dark, with some pale scales on ventral side of basal half; palps short and broad with a few pale scales at base of segments 2, 3, 4; legs with inconspicuous pale scaled knee spot and apical, tibial hind spot, remainder of legs all dark scaled; tergites dark-scaled with pale basal bands sometimes constricted in the middle; sternites pale-scaled with lateral apical dark patches; wings without patch of remigial setae at base of subcosta .............. .. .........................................................................................................................Halaedes australis –A large mosquito, proboscis and palps completely dark-scaled, palps short, about one-sixth the length of the proboscis; tergites dark-scaled with thin basal pale band and sometimes with basal lateral pale patches, sternites dark-scaled with basal lateral pale patches; ventral side of wing with patch of remigial setae at base of subcosta (Fig. 12) (distribution restricted to the Chatham Islands)..........................................................................................................Opifex chathamicus 12 (9) –Abdominal sternites generally pale-scaled but with a few dark scales scattered medially, (a medium-sized, light brown mosquito; tergites dark-scaled with basal pale bands sometimes extending medially; hind legs with femur pale to tip, except for dark scales along the length dorsally, and pale scaling at knee spot and apical hind tibial spot, remainder of legs all dark-scaled) .............. ................................................................................................................ Culex quinquefasciatus –Abdominal sternites not as above (abdominal tergites with either pale basal bands or basal lateral pale patches or all dark-scaled) .............................................................................................. ...13 (continued)

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Fig. 9–11 9, Culiseta tonnoiri wing (drawn from slide mounted specimen). 10, Scale patterns on adult hind leg. 11, Arrangement of abdominal scale patterns in adult mosquitoes.

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Fig. 12 Features of wing venation (ventral side) showing important features for identification (redrawn from Belkin 1962).

13 (12) –Abdominal sternites dark-scaled with basal lateral patches of pale scales; proboscis and palps all dark-scaled; hind femur largely pale-scaled for three-quarters its length, remainder of leg all dark scaled ................................................................................................................................ .14 –Abdominal sternites with medial dark patches and apical lateral dark patches, with varying degrees of pale scaling; proboscis with pale scales on ventral surface; palps either all dark scaled or with some pale scaling; femur predominantly dark-scaled on anterior surface and remainder of leg dark-scaled except for conspicuous pale-scaled knee spot, and apical hind-tibial spot (Fig. 10)...................................................................................................................................15 14 (13) –A medium-sized, dark mosquito; ventral side of wing without remigial setae at base of subcosta; tergites all dark-scaled (sometimes with small basal lateral pale patches); sternites dark-scaled with basal lateral patches of creamy/yellow scales ................................Coquillettidia iracunda –A large bronzy/gold mosquito; ventral side of wing with patch of remigial setae (10 or more) at base of subcosta; tergites with bronzy dark scales and basal lateral pale patches; sternites extensively pale-scaled ................................................................................. Coquillettidia tenuipalpis 15 (13) –Abdominal tergites dark-scaled with pale basal band extending medially and sometimes curved ................................................................................................................................................... 16 –Abdominal tergites dark-scaled with large, straight and wide pale basal bands (Fig. 11); (sternites extensively dark-scaled, sometimes with basal lateral pale patches, pale scaling usually creamy; knee spots and apical, tibial hind spot usually yellowish (Fig. 10); small mosquito of generally light or medium/light brown colour; smallest species in Culex pervigilans complex, usually found in the leaf axils of Collospermum hastatum (Colenso)) .........................................Culex asteliae 16 (15) –A medium to large, dark-brown to black mosquito; palps dark scaled with pale scaling on segments 3 and 4; scutum with predominantly pale scaling (usually whitish, creamy or golden); tergites usually dark-scaled with pale basal bands, slightly constricted laterally; sternites with varied amount of dark scaling, but always with basal medial dark patch and apical lateral dark patches, pale scaling is usually whitish (Fig. 11); pale scaled knee spots and apical tibial hind spot pale scaled, usually large and conspicuous ............................................................. .Culex pervigilans –A small dark mosquito; palps dark scaled with very few or no pale scales; scutum with predominantly bronzy scales; tergites predominantly dark-scaled with fairly narrow and straight pale basal bands, sometimes slightly curved; sternites predominantly dark-scaled except for lateral basal patches of pale scales; pale scaled knee spot and apical tibial hind spot inconspicuous ..... .............................................................................................................................. Culex rotoruae Note: Identifying New Zealand Culiseta Felt on the basis of female characters is extremely difficult. Habitat and geographical localities have been used here but they should not be regarded as reliable, although this may assist in preliminary identification. Confirmation should be sought in other ways. The most reliable methods are examination of male genitalia, or larvae, which have been reared in series, including all stages (Belkin 1968).

108 DISCUSSION AND FUTURE RESEARCH These keys combine observations of supplementary taxonomic characters and taxonomic descriptions from published literature to enable easy and accurate identification of specimens. Entomologists who are not familiar with the identification of mosquitoes have trialled these keys. However, further clarification of identities is needed for some species. Culiseta tonnoiri and Cs. novaezealandiae are considered here as valid species, although Belkin (1968) did not regard Cs. novaezealandiae as a separate species. However, he postulated that there may be more than one species of the subgenus Climacura Howard, Dyar & Knab present in New Zealand, but that the differences in the larvae are probably individual or sex-dependent variations in a single species. Samples from different populations of Culiseta need to be reared to determine the range of variation in these two species. Molecular research could also be used to confirm identification of Culiseta species (Bourguet et al. 1998), and this also applies to Cx. pervigilans, in which there is obvious variation in larval and adult characteristics. A description is also lacking for the larvae of Coquillettidia Dyar. Coquillettidia iracunda is an avid biter of humans (A. Snell pers. obs 2002), and belongs to the same subgenus as Coquillettida (Coquillettidia) linealis (Skuse), a serious pest in Australia that bites humans and domestic animals (Lee et al. 1988; Jeffery et al. 2002). This species has been shown to be a highly competent vector of Ross River virus, and a moderately competent vector of Barmah Forest virus (Jeffery et al. 2002). The phylogenetic relationships between Australian and New Zealand Coquillettidia species need clarification. However, Cq. iracunda also warrants further investigation on its potential vector competence and vectorial capacity for Ross River virus and other arboviruses.

ACKNOWLEDGMENTS I am grateful to Phil Sirvid (Te Papa), John Early and Rosemary Gilbert (Auckland Museum), and Trevor Crosby (NZAC) for their assistance with museum collections. Thanks to Barry Snell, José Derraik, Paul Leisnham, Robyn Sinclair, Shane Geange, Rob Kennedy, and James Wakefield for their assistance with field collections, and to New Zealand Biosecure for the Oc. camptorhynchus specimens. Thanks also to Nga Manu Nature Reserve and Karori Wildlife Sanctuary for access to conduct trapping. Special thanks to Shane Geange for the illustrations. I also thank Mary McIntyre, Craig Williams, Dave Slaney, Phil

New Zealand Journal of Zoology, 2005, Vol. 32 Sirvid, Rochelle Knox, Allen Heath, and Trevor Crosby for testing the key and/or reviewing the manuscript. Thanks to the University of Otago for funding support, and also thanks to the two anonymous referees for greatly improving the text.

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