Chironomus storai

Author: (Goetghebuer, 1954)

Diagnosis (Material in coll. Wülker)
Exuviae 7.9-8.9mm long (n=3).
Cephalothorax: Cephalic tubercles conical, 100-160µm high (n=3). Frontal setae 65µm long (n=1). Thoracic horn much branched.
Abdomen: Hook row II medially interrupted, length of row 0.19, 0.2 (0.13 gap) 0.17, 0.2x width tergite; hooks 32/31, 29/35, 33/29 (n=3). 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 tergite II spreading laterally in front of the anterior adhesion marks (101a.jpg). Armament of tergites more extensive: e.g. tergite IV with marmoration restricted to the lateral margin of the point patch, points usually reaching as far laterally as seta D2 (101b.jpg). Anterior points of tergite VI arranged in short rows which are aligned in horizontal rows across the centre of the point patch but become disorganized and irregularly arranged laterally (101c.jpg). Anterior points of sternite VII spiculate and grouped in irregular rows; those of the tergite more robust, resembling in shape the smaller points on the preceding tergite. On tergite VII the short rows of points become disorganized before the anterior adhesion marks. Pedes spurii B of segment II conspicuous. Pleura IV unarmed. Conjunctives III/IV and IV/V with a small lateral seta, V/VI and VI/VII unarmed or very weakly armed. Comb of segment VIII with 1-4 dark apical teeth. Lateral taeniae of segments V-VIII: 4,4,4,5.
Anal segment: Fringe of anal lobe with 82-100 taeniae (n=3).

Note: Possibly indistinguishable from Chironomus lob-pe2a; the low hook number (total 62-64, as compared with 75/76 for pe2a) may be diagnostic.

Species keys out at Page 146: Chironomini 43 Chironomus of the Text Key.

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

Ecological notes
Alpine pools above 1,700m.