Holarctic Chironomus (s.l.) - Benthalia carbonaria type

Benthalia carbonaria group species from Hainan Island. China:

Based on two incomplete adult males.

Color: Thorax dark brown, abdominal segments largely dark brown with a narrow darker band at the posterior margin of most segments, legs apparently yellowish.
AR and LR1 not known. Wing length 2.66-3.00 mm, width 0.63-0.70 mm; VR about 1 (0.99); 18 setae in squamal fringe, 2-3 SCf on brachiolum.
Head: Antennae missing on both specimens; frontal tubercles 40 x 20 µm; palpal proportions (µm) 21.5 : 24 : 59 : 121.
Clypeus width about 0.97 the diameter of the antennal pedicel; 12-18 clypeal setae.
Thoracic setae - 1-2 acrostichals as common for the genus; 11-12 dorsocentrals; 5 prealars; 1 supraalar; scutellar with setae in 2 rows, 7-12(?) in anterior row, 11-13 inposterior row.
Legs: Lengths and proportions (micron):

	Fe	Ti	Ta1	Ta2	Ta3	Ta4	Ta5	LR	F/T
PI	940	763	-	-	-	-	-	-	1.24-1.28
PII	998	905	512	278	210	120	118	0.59	1.12
PIII	1050	1115	800	425	330	180	135	0.70-0.73	0.92-0.96

Abdomen darkened at least to some extent; 4 setae along the mid-line of tergite IX and a lateral seta on each side at the base of the anal point.
Superior volsella not like any of the Strenzke (1959) types, with the base extending distally, from the top of which the long, curved scleritised part arises; Inferior volsella club-like, setae simple. Gonostylus only moderately swollen and reducing only near tip; anal point not as thickened as in some other species and narrower at its base.

Found: China - Hainan Island.

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