Chironomus pe12

Form described by Langton, 1991

Diagnosis (n=1, specimen ex. coll. C.J. Webb labelled "C sp 7" in coll. R.S. Wilson.)
Exuviae 10.3mm long.
Cephalothorax: Cephalic tubercles large, LxB 150x163µm. Frontal setae 83µm long. Thoracic horn much branched; basal ring of horn 170x70µm; tracheal patch 113x33µm; about 11 tracheoles across; 3µm in diameter. Tracheal patch of thoracic horn without an "eye". Thorax granulation very weakly developed, virtually smooth.
Abdomen: Hook row II entire, length of row 0.61x width tergite; hooks 87. (Hook row with fewer hooks than in Chironomus salinarius despite the larger size of the specimen.) 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. The point patches increase in extent from tergite II to V, but on VI the patch is more or less reduced. 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. Sternites III and IV with an anterior transverse band of fine shagreen which laterally spreads posteriorly for the sternite length on III, and for about two thirds sternite length on IV. Pleura of segment IV without spinules. Comb of segment VIII with 4 small, broad, apiculate teeth, set on the end of an elongate ventral cuticular mound which exceeds appreciably the apico-lateral corner of the segment.
Anal segment: Fringe of anal lobe with 166/169 taeniae.

Form keys out at Page 163: Chironomini 60 Chironomus of the Text Key.

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