Author: Brundin, 1947
Diagnosis
Exuviae 4.0-5.6mm long (m=4.6mm, n=10).
Cephalothorax: Thoracic horn conspicuous, 240-385µm long (m=305µm, n=10), varying from nearly smooth to densely covered with small points; ThR 7.7-18.4 (m=12.1, n=10). Four dorsocentral setae, the first, third and fourth thick, the second conspicuously thinner.
Abdomen: Hook row II a discrete pad or band of hooks, less than 0.34x width of segment II, usually of three or more transverse rows of hooks. Points of median and posterior bands of much the same size and form. Median point bands of tergites III-VI very transverse; separate from the posterior band, joined to it laterally or joined to it medially as well, but usually distinct. Posterior transverse point band on tergite III not extending further laterally than the apical band. Tergites and sternites without granulation (077e.jpg). Pedes spurii B on segment II conspicuous. Forked or branched setae rare and usually confined to the apical sternites. Lateral setae of the posterior segments longer and more robust than in Orthocladius rubicundus; seta 2 VII 60-110µm long (m=87µm, n=7); seta 4 VIII 85-175µm long (m=121µm, n=8).
Anal segment: Anal lobe ratio 1.8-2.2 (m=1.9, n=8). Anal lobes without apical teeth, or rarely with small colourless teeth; the macrosetae at most weakly curved at tip, often straight, setae 0.52-0.63x length of the anal lobe (n=5). Fringe absent.
(Linked adult male: Langton and Pinder, 2003a)
Species keys out at Page 864: Orthocladiinae 275 Orthocladius of the Text Key.
Distribution
Holarctic species: widespread in (northwest) Europe.
(For more information see module IdentifyIt – file: Orthocladiinae).
Ecological notes
Northern and montane streams and lakes.