Chironomus acutus Das, N., Majumdar, U., Mazumdar, A., & Hazra, N., 2016 (Junior homonym of C. acutus Goetghebuer 1928 - New name required.)
Since the name refers to the shape of the Superior volsella, Chironomus aguzza is suggested. Adult
Male:
Total length 4.52-4.70 mm. Wing length 2.08-2.50; width 0.64-0.76. AR 2.95-3.02.
Head and thorax light brown, wing light yellow, veins brown; postnotum dark brown. Legs and abdomen pale yellow; tergites II-IV with faint spots.
Frontal tubercles 82-90 µm long and 34-40 µm wide; clypeus 170-180 µm long and 136-140 µm wide, with 18-20 setae. Ratio of papal segments (µm): 68-85 : 34-51 : 170-187 : 255-272; P5/P4 abt 1.45-1.5: P5/P3 abt 1.33-1.36.
Thoracic setae: 10-12 acrostichals; 12-14 dorsocentrals; 6-8 prealars; 16-18 biserial scutellars.
2 Scf on brachiolum, 16-18 setae in squamal fringe; VR 1.12-1.14.
Leg lengths (micron) and proportions:
| Fe
| Ti
| Ta1
| Ta2
| Ta3
| Ta4
| Ta5
| LR
| F/T
| BR
| PI
| 1120-1160
| 960-1000
| 1560-1640
| 840-920
| 760-800
| 640-680
| 320-360
| 1.59-1.62
| 1.16-1.17
| 2.62-2.65
| PII
| 1080-1120
| 960-1000
| 640-720
| 320-360
| 200-280
| 160-220
| 120-160
| 0.64-0.67
| 0.96-1.12
|
| PIII
| 1000-1040
| 1200-1260
| 880-920
| 480-520
| 320-360
| 240-320
| 120-160
| 0.69-0.73
| 0.83
|
| Lacks a beardAbdomen pale yellow, Tergites II-IV faint spots; Tergite IX with 15-17 setae, some possily in clear pale spaces.
Anal point 82-87 µm long with an expanded end; Superior volsella somewhat sickle shaped, of D(e)-type of Strenzke (1959); Inferior volsella reaching about to end of anal point and(1/3 of length of gonostylus), with 10-12 incurved setae near apex; gonostylus only moderately swollen and narrowing markedly from about midpoint.  Female: not described. Pupa: Length 5.56-6.92 mm.; wing sheath 1.36-1.44 mm long.
Yellowish, exuviae grey. Frontal apotome triangular with subapical frontal setae 30-38 µm long. Cephalic tubercles cone-shaped 86-92 µm long and 64-69 µm wide. Basal ring of thoracic horn bean shaped.
Abdomen yellowish brown, tergites II-VI with median shagreen, VII with a single semicircular patch of basomedian shagreen, VIII with little shagreen. &nsp;Hook row comprising 52-56 hooklets. Segment II with caudolateral PSB (69-72 x 52-56 µm), with a PSA (77-82 x 65-69 µm).
Caudolateral spur with two spines. 160-166 taeniae in multiple rows on anal lobe.  Fourth instar larva: Deep red in color, 5.68-8.60 mm long, VT 880-1120 µm long, anal tubules 560-880 µm long. &nsp;There is no mention of lateral projections or indication of whether the ventral tubules are coiled or straight.
Mentum 163-184 µm wide, possibly of type I with the central trifid tooth of type IA.
Ventromentum 52-66 µm wide with a serrated margin, distance between them 73-84 µm.
Premandible illustrated with inner tooth narrower than the outer tooth. Pecten epipharyngis with 12-14 teeth, two apical ones dark brown.
Mandible 220-238 µm long, with pale apical tooth and the inner teeth dark (type IIIC); MTR perhaps 0.29.  Noted as close to C. incertipenis and C. ramosus in structure, but thoracic chaetotaxy is quite different. Found: India - Type locality Itanagar (27.03°N. 93.63°E, 440 m a.s.l.) Arunachal Pradesh. [ Return to Index | Go to References ] |