Chironomus acutiventris

Author: Wülker, Ryser and Scholl, 1983

Diagnosis (material leg. I.I. Kiknadze)
Exuviae 7.7-8.5mm long (n=4).
Colour: Contrast in colour between thorax and abdomen not so strongly marked: specimens dark anteriorly also have the abdomen infuscated; outer margin of the anal lobes coloured except at base.
Cephalothorax: Cephalic tubercles LxB 128x105-145x120µm (n=3). Frontal setae 52-62µm long (n=3). Basal ring of thoracic horn 120x60-145x72µm. Tracheolar patch of thoracic horn without an "eye", patch 88x20-96x32µm (n=4); 12-17 tracheoles across; 2.0-2.8µm in diameter. Thorax smooth, or clearly granulate anteriorly only, with or without a few large granules near suture.
Abdomen: Hook row II entire, length of row 0.59x width tergite (n=1); hooks 113, 122 (n=2). Armament of tergites II-VI not so strongly waisted and with the posterior transverse band not successively increasing in extent to tergite VI; usually reduced on VI. Points of tergites III-VI suddenly larger at about level seta D5. Sternites III and IV without a complete anterior transverse band of shagreen, lateral shagreen bands very fine and inconspicuous, on III not spreading inwards anteriorly. Pleura of segment IV extensively armed with relatively large spinules: about 20µm long, 1µm broad at base (100c.jpg). Comb of segment VIII on the end of an elongate ventral cuticular mound with 2-5 teeth (n=4).
Anal segment: Anal lobes straight-sided, each lobe with 69-90 fringe taeniae (n=3).

Species keys out at Page 186: Chironomini 83 Chironomus of the Text Key.

N+C Europe, see also Chironomus acutiventris bavaricus.
(For more information see module IdentifyIt – file: Chironominae).

Ecological notes
Shallow standing water in mountains.
Running water with sandy bottom (Wülker, 1999b).