Heterotrissocladius subpilosus

Author: (Kieffer, 1911)

Diagnosis (Material in coll. ZSM)
Exuviae 5.4-6.1mm long (m=5.8mm, n=8).
Cephalothorax: Cephalic tubercles absent. Thoracic horn 370-410µm long (m=400µm, n=7), small-toothed; ThR 6.1-8.0 (n=4). Wing sheaths with pearl row.
Abdomen: Armed tergites with small points which are gradually a little larger posteriorly on each segment (040a.jpg). Tergites without a median transverse row of strong points. Points on tergites short, giving a finely dotted appearance (as in Heterotrissocladius marcidus) but with only three lateral taeniae on segment VII (as in Heterotrissocladius grimshawi). Postero-lateral corner of segment VII rounded. Sternite of male armed with a posterior band of conspicuous points along the evenly curved posterior margin; of female with a pair of triangular projections, each stiffened with an embedded spine (039h.jpg). Pedes spurii B of segment II absent or weak. Three or four lateral setae on segments II-VI, not taeniate; segment VII with three taeniate setae, and all those on segment VIII taeniate.
Anal segment: Anal lobe ratio 1.8-2.0 (n=8). Fringe of anal lobe with 19-25 taeniae (m=22.8, n=8).

Species keys out at Page 626: Orthocladiinae 38 Heterotrissocladius of the Text Key.

Holarctic species: Northern (arctic) Scandinavia.
(For more information see module IdentifyIt – file: Orthocladiinae).

Ecological notes
Northern lakes.