Tanytarsus pe5a

Form described by Langton, 1991

Diagnosis (n=1)
Exuviae 3.3mm long.
Cephalothorax: Cephalic tubercles apparently absent. Frontal setae 113µm long. Antennal sheath base without projection. Thoracic horn 685µm long, densely covered with minute setulae, 13µm long, for the apical two-thirds; ThR 19.6 (141h.jpg). Posterior thoracic mound weak, rounded. Wing sheaths rounded apically, pearl row absent.
Abdomen: Length hook row II 0.3x width tergite; hooks 75. Armament of tergites III-VI on slightly yellowed patches. Point patches of tergite III longitudinally broad oval, less than one quarter the length of the segment; patches joined by a transverse field of shagreen; tergite unarmed behind the point patches. Tergites IV and V with the armament arranged in longitudinal bands. Armament tergite IV strong, 72µm long. ArR III-VI 1.04 : 1.0 : 1.04 : 0.63. Postero-lateral comb of segment VIII truncate posteriorly, 25µm wide; with 6 marginal teeth; comb claw-like, the outer marginal tooth the largest and curved posteriorly, the remaining teeth progressively shorter inwards. Lateral taeniae of segments V-VIII: 0,1,3,4.
Anal segment: Anal lobe ratio 1.45. Fringe of anal lobe with 27/28 taeniae, forming a complete series.

Form keys out at Page 466: Tanytarsini 107 Tanytarsus of the Text Key.

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

Ecological notes
Loch Assynt, Scotland.