Form described by Langton, 1991
Diagnosis
Exuviae 3.9-4.8mm long (n=6).
Cephalothorax: Cephalic tubercles 27-50µm long (n=5); frontal setae 33-40µm long (n=5). One branch of the thoracic horn is very long and stiff, extending forwards for over half the exuvial length and not itself branched for its proximal half, the other initial branches small and clustered around its base. Posterior thoracic mound weakly indicated.
Abdomen: Hook row II medially interrupted, length of row 0.09, 0.10 (0.05 gap) 0.09, 0.10x width tergite (n=2); hooks 5/5-8/8 (n=6). Dorsal abdominal armament restricted to large points set on the apices continuous posterior transverse mounds on tergites III-VI. Toothed mounds present on sternites II-V. Comb of segment VIII thorn-like, set close behind the fourth lateral taenia, comb 130-155µm long (n=6). Lateral taeniae of segments V-VIII: 4,4,4,(3)4.
Anal segment: Fringe of anal lobe with 28-40 taeniae (n=6), of similar length.
Note: This form could be an extreme of Cryptotendipes usmaensis, but the weak posterior thoracic mound seems diagnostic. Also the posterior median setae of the mid-sternites are usually forked or branched, whereas in usmaensis this is rare.
Form keys out at Page 109: Chironomini 6 Cryptotendipes of the Text Key.
Distribution
England, Spain, Tunisia.
(For more information see module IdentifyIt – file: Chironominae).
Ecological notes
Rivers.