C. magnivalva Kieffer, 1917Synonyms: Chironomus crassiforceps - incorrect synonymy by Guryev et al. (2001) and Peck et al. (2002).In Bold Bin: BOLD:AAJ4269
The nearest neighbour is BOLD:ACC5271 which contains C. crassiforcepsAdult:
A greenish brown species with an enlarged hypopygium, typical of species that mate on substrate. Male:
Antennal ratio (AR): Kieffer gave the AR as about 2, while Freeman pushed this up to 2.5. However in one specimen that he measured, it is only about 1.5. AR here is measured from slide mounted secimens: 1.66 (1.46-1.80).
Wing Length: 2.54 (2.32-2.83) mm; wing width: 0.64 (0.48-0.68) mm., VR about 0.92 (0.85-1.06); 2.3 (2-3) Scf on brachiolum; 11.1 (10-13) setae on squamal fringe.
Head: Frontal tubercles about 23-36 µm., generally columnar, and about twice as long as wide; 28.6 (19-44) clypeal setae. Palpal proportions (micron): 48 : 46 : 155 : 147 : 213; P5/P4 1.42 (1.20-1.75); P5/P3 1.37 (1.15-1.57).
Thoracic setae: Acrostichals 12.1 (10-13); Dorsocentrals 17 (15-21); prealars 5 (4-6); scutellars in two rough rows, 4-9 in anterior row, 8-11 in posterior row, total 15.3 (13-17).
LR about 1.59.
Leg lengths (microns) and proportions as follows:
| Fe
| Ti
| Ta1
| Ta2
| Ta3
| Ta4
| Ta5
| LR
| F/T
| Ta4/Ti
| PI
| 1143
| 1021
| 1615
| 800
| 699
| 695
| 341
| 1.46-1.74
| 1.04-1.29
| 1.27-1.67
| PII
| 1172
| 1149
| 569
| 329
| 266
| 192
| 161
| 0.47-0.52
| 0.94-1.08
|
| PIII
| 1323
| 1338
| 791
| 446
| 396
| 234
| 187
| 0.55-0.69
| 0.97-1.00
|
| Ant Ta4/Ti - 0.68; FeI/FeII - 0.92-1.03
Illustration of the hypopygium of C. magnivalvaNo setae on TIX; anal point downturned with a flattened triangular tip. Superior volsella normal, closest to E(i) type of Strenzke 1959; Inferior volsella also relatively normal, with simple setae on inner margin only, and extending to mid-point or tip of gonostylus. Gonostyle normally broadest at base, but sometimes quite swollen, narrowing slightly and evenly along its length; with numerous spines rather than setae at the tip. Female:
Coloration essentially as in male; brownish green darkening over the abdominal tergites.
Wing length 2.97 (2.64-3.44) mm, width 0.95 (0.85-1.01) mm; VR 0.95 (0.87-0.97). 2.8 (2-3) Scf on brachiolum; 16.3 (13-20) setae on squamal fringe.
Head: Frontal tubercles about 25-40 µm long and 11-18 µm wide, about twice as long as wide; antennal proportions (micron, with proportion of neck in brackets) 129 (0.26) : 91 (0.39) : 98 (0.39) : 97 (0.45) : 170. AR about 0.40 (0.37-0.45); A5/A1 1.33 (1.15-1.60). Palpal proportions (micron): 48 : 43 : 146 : 168 : 231.
Thoracic setae: about 13 (10-17) acrostichals; 3.85 (3-6) linear humerals; 20.7 (14-27) dorsolaterals; 5.1 (4-6) prealars; 1 supraalar; scutellars in two rows - 6.2 (3-8) in anterior row and 10.6 (9-13) in posterior row.
Mean leg measurements (microns) and proportions as follows:
| Fe
| Ti
| Ta1
| Ta2
| Ta3
| Ta4
| Ta5
| LR
| F/T
| BR
| PI
| 1138
| 954
| 1513
| 715
| 631
| 645
| 323
| 1.50-1.69
| 1.13-1.24
| 0.57-0.78
| PII
| 1160
| 1150
| 600
| 325
| 250
| 185
| 155
| 0.52-0.53
| 1.00-1.02
| -
| PIII
| 1300
| 1370
| 860
| 470
| 405
| 230
| 190
| 0.62-0.65
| 0.94-0.97
| -
| BR 1.38-1.62; FeI/FeII - 0.96-0.99 GcIX with about 4 setae; segment X larger than usual and oval in shape with about 19.5 (14-24) setae. Cercus essentially oval/rectangular with at best a very small basal extension on dorsal side.
Cercus and segment X of C. magnivalvaA possible point of difference in the morphology of the males is that, while the gonostyle of C. magnivalva narrows evenly to the distal end, that of C. crassiforceps appears to remain the same width for most of its length and then rounds off. Molecular Data:
mtCOI AF192212 (originally as C. crassiforceps, but now corrected)
mtcytB AF192181 (originally as C. crassiforceps, but now corrected)
As noted above, specimens of C. magnivalva and those of C. crassiforceps are in different BOLD Bins. Found: Northern Territory - Island Lagoon, Magela Creek, Alligator Rivers region (12.57°S, 132.88°E).
Queensland - Noosaville; Sarina (25.36°S, 149.20°E); Townesville (Type locality); South Townsville (19.43°S, 146.80°E); Common,
Townsville (19.36°S, 146.70°E).
Also: - Motu Kö, Pukapuka, Cook Islands (10.88°S, 165.51°W) (E.H. Bryan Jr., Bishop Museum).
Cytologically identical material has been collected from Lautoka (17.67°S, 177.50°E) and Laucola Bay (18.25°S, 178.33°E), Viti Levu, Fiji and Punaauia, Tahiti (17.53°S, 149.57°E). [ Return to Index| Go to C. crassiforceps | Go to References ] |