Chironomus nuditarsis

Author: Keyl, 1961

Diagnosis (Confirmed with original Strenzke material.)
Exuviae 11.4-15.5mm long (n=6).
Colour: Colour gold to golden-brown. (Differs from Chironomus balatonicus and Chironomus prasinus in colour: more evenly golden-brown to brown, with the thorax darker, whereas the other two forms have nearly colourless anterior segments to the abdomen and the thorax has a distinct dark lateral band and darkened anterior.)
Cephalothorax: Cephalic tubercles LxB 170x143-237x188µm (n=4). Frontal setae 60-90µm long (n=4). Thoracic horn much branched; basal ring of horn 200x100-300x130µm; tracheal patch 150x47-235x60µm; 13-24 tracheoles across (n=7); 3.5-4.0µm in diameter. Tracheal patch of thoracic horn without an "eye". Thoracic granulation strong and extensive; reaching the suture dorsally at least as far as the anterior edge of the wing sheath.
Abdomen: Hook row II entire, length of row 0.51-0.58x width tergite (n=4); hooks 79-113 (n=6). Armament of tergites II-VI in the form of an undivided, usually extensive patch of strong points, the points in each segment increasing in size posteriorly. Armament of tergites II-VI not strongly waisted and with the posterior transverse band not successively increasing in extent to tergite VI; usually reduced on VI. The point patches increase in extent from tergite II to V, but on VI the patch is more or less reduced. Median point patches of tergites III-V with at least some marmoration. Shagreen of sternite II reduced, the lateral longitudinal bands only joined to the median patch anteriorly and, sometimes, posteriorly (the lateral bands may be very reduced in extent posteriad). Shagreen of sternites III and IV forming a lateral longitudinal band on each side, which may spread inwards anteriorly. Parasternites II shagreened; apical spinule patches of paratergites V-VII well-developed. Pleura IV armed. Comb of segment VIII with (4)7-14 (n=6), set on the end of an elongate ventral cuticular mound which exceeds appreciably the apico-lateral corner of the segment. Lateral taeniae of segments V-VIII: 4,4,4,5.
Anal segment: Fringe of anal lobe with 134-215 taeniae (n=5).

Species keys out at Page 158: Chironomini 55 Chironomus of the Text Key.

Widespread in Europe, Middle East.
(For more information see module IdentifyIt – file: Chironominae).

Ecological notes
Generally in organically polluted ponds.