Chironomus pe26

new form

Diagnosis (coll./leg. Ina Balzer)
Exuviae 8.0, 9.1mm long (n=2).
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 124, 144µm long (n=2). Frontal setae 52, 62µm long (n=2). Basal ring of thoracic horn 160x70µm, tracheolar patch 108x30µm (n=1); 9/10 tracheoles across (n=2); 2.3, 2.7µm in diameter. Tracheolar patch of thoracic horn without an "eye". Thorax more or less smooth.
Abdomen: Hook row II entire, length of row 0,56, 0.62x width tergite (n=2); hooks 107, 118 (n=2). 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. Sternites III and IVwith lateral shagreen bands broadly joined anteriorly (the lateral bands may be reduced on IV). Pleura of segment IV spinulate. Comb of segment VIII with 2/3 narrow apiculate teeth, set on the end of an elongate ventral cuticular mound which exceeds appreciably the apico-lateral corner of the segment.
Anal segment: Anal lobe with 83, 118 fringe taeniae (n=2).

Form keys out at Page 174: Chironomini 71 Chironomus of the Text Key.

(For more information see module IdentifyIt – file: Chironominae).

Ecological notes
R. Donau.