Oriental Chironomus: C. ramosus

Chironomus ramosus Chaudhuri et al. 1992

This species is in BOLD Bin: BOLD:AAW3997.

Adult

Male:
Body 5.77 (5.62-5.89) mm.  Wing length 2.33 (2.27-2.40), wing width 0.72 (0.70-0.76)  VR 1.01 (1.00-1.03).
Head: AR 3.86 (3.72-3.94).  Frontal tubercles small; ratio of palp segments: 14 : 11 :47 : 48 : 66.  Clypeal setae 20 (18-20).
Thorax yellow, postnotum pale brown; 2 antipronotal setae.  Mesonotum with 4 brown vittae; fore tibial scale with 4 long setae; tarsomeres of foreleg dark brown, Ta1-3 of mid and hind legs brown at apex, Ta4 & 5 brown.
Leg proportions and ratios (units):
Leg pale; lengths (micron) and proportions as follows:

Male	Fe	Ti	Ta1	Ta2	Ta3	Ta4	Ta5	LR	F/T	BR
PI	30	29	43	21	18	15	7	1.48	1.03	no beard
PII	31	29	18	10	7	4	3.5	0.62	1.07	-
PIII	38	35	25	14	11	6	4	0.72	1.09	-

Abdomen: Greenish yellow, tergites II-VI with brown oval spot medially; VII & VIII with broad brown patch.

Adult male of C. ramosus (Chaudhuri, Das and Sublette 1992)

Curved anal point figured as tapering to end, beak-like superior volsella (as in C. samoensis, C. flaviplumus, etc.), S-type, closest to Fig. a of Strenzke (1959); setae of inferior volsella finely branched. Gonostylus moderately swollen, narrowing gently over posterior half to third.

Female:
Body 4.68 (4.53-5.12) mm. Wing length 2.59 (2.49-2.66), wing width 0.88 (0.82-0.95).
Antenna 5 segmented, relative lengths 10 : 7.5 : 7 : 6.5 : 12. AR 0.38, A5/A1 about 1.2.

Female genitalia of C. ramosus (Chaudhuri, Das and Sublette 1992)

TX shown as long, curved, but inner region with setae not shown; other specimens show it is about 1.67x longer than greatest width, with 14 setae; Cercus with short dorsal margin, then curved around to ventral base; no obvious basal bulge.

Found: Type locality - Satgachhia, West Bengal, INDIA.
Other localities:
India - Hooghly, West Bengal; Pune; Cachar hills, Assam.

Larva, pupa and adult described by Chaudhuri, Das & Sublette (1992). Chromosomes described by Nath & Godbole (1997). In their map, chromosome I is comprised of arms D and C, chromosome II of arms F and B; chromosome III of arms A and E, and chromosome IV is arm G. As noted, the nucleolus in the map is at 11B in arm B, but in other specimens, the nucleolus is in arm F at 10D. Since the available specimens have all come from an inbred laboratory stock, it is not clear what the situation is in natural populations (see C. ramosus immatures)
Cytologically close to C. flaviplumus Type B and C. incertipenis.

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