Chironomus alternans b - Martin and Porter 1977; Lentzios and Stocker 1979; Lentzios et al. 1980, Martin and Lee 1981 and 1984, Martin and Cranston 1995.
Chironomus pseudoppositus (manuscript name) - Martin 1974.
Chironomus pseudoppositus (nomen nudum) - Martin 1969b; Cranston and Martin 1989.
The adults are very similar to those of C. oppositus, but are generally smaller and darker in colour.
Males: Head, antennae and mouth parts brown. Frontal tubercles present, length about 10-29 micron. Thorax generally brown with purplish brown stripes; thorax pruinose.
Wings with anterior veins hardly darker than posterior, crossvein slightly darkened.
Wing length 2.8 - 3.6 mm.
Male abdomen generally black with a white posterior margin on the anterior segments. Hypopygium similar to those of other members of the C. oppositus group.
Legs yellowish green, unbanded.
Leg lengths (microns) and proportions as follows:
|
|
Fe |
Ti |
Ta1 |
Ta2 |
Ta3 |
|
PI |
1265 |
1045 |
1785 |
910 |
740 |
|
PII |
1310 |
1165 |
725 |
395 |
295 |
|
PIII |
1420 |
1425 |
1050 |
585 |
455 |
|
|
Ta4 |
Ta5 |
LR |
F/T |
BR |
|
PI |
645 |
290 |
1.5-1.8 |
1.18-1.23 |
1.6-2.1 |
|
PII |
190 |
140 |
0.62-0.63 |
1.12-1.14 |
|
|
PIII |
280 |
170 |
0.72-0.75 |
0.98-1.01 |
|
Females: Wing length 2.8 - 4.2 mm; width at cross vein 0.96 - 1.20 mm.
Head with frontal tubercles of variable length: 19 - 48 micron; about 27 - 55 clypeal setae. Thorax and wings similar to those of males. Thoracic setae: Achrostichal abt. 17 - 22; Dorsolateral 23 - 35; Prealar 5 - 7; Scutellum, ant row 9 - 14, posterior row 11 - 20.
Leg lengths (microns) and proportions as follows:
|
|
Fe |
Ti |
Ta1 |
Ta2 |
Ta3 |
|
PI |
1550 |
1217 |
2310 |
1140 |
925 |
|
PII |
1540 |
1417 |
810 |
413 |
300 |
|
PIII |
1660 |
1695 |
1200 |
653 |
510 |
|
|
Ta4 |
Ta5 |
LR |
F/T |
BR |
|
PI |
860 |
373 |
1.68-1.82 |
1.23-1.32 |
1.6-1.7 |
|
PII |
195 |
150 |
0.56-0.61 |
1.09-1.11 |
|
|
PIII |
300 |
188 |
0.67-0.72 |
0.98-0.99 |
|
Types: Holotype male: Asquith, New South Wales (-33.68, 151.10), 20.ii.1963, (leg. J. Martin) (♂2)
Allotype female: Data as for Holotype. (♀3)
Paratypes: 3♂, 5♀, data as for Holotype, but various dates in 1963.
Type material currently in collection of Jon Martin, but will eventually be distributed to the ANIC and other institutions.
Found: Australian Capitol Territory - Australian National University wildlife reserve.
New South Wales - Asquith (type locality)
Queensland - Auchenflower.
South Australia - 1 Km n. Denial Bay; Koppio; Eyres Waterhole, Streaky Bay; Parachilna; 23 Km n. Quorn; Tumby Bay.
Tasmania - Bakers Beach, 3 km nw Queenstown.
Victoria - Armadale; Beechworth; Box Hill North; Bulleen; 7 Km s. Castlemaine; Eildon; North Balwyn; Edwardes Lake, Reservoir; Ringwood North; Templestowe Lower; Warburton; Warrandyte South; Wartook Reservoir, Grampians; Melbourne Water Metropolitan Farm, Werribee.
Although classed as a nomen nudum, this species was described and types designated by Martin (unpublished Ph.D. Thesis 1966).