Orthocladius saxosus

Author: (Tokunaga, 1939)

Diagnosis (Material in coll. ZSM; in part after Soponis, 1990a - in italics)
Exuviae 3.3, 3.8mm long (n=2).
Cephalothorax: Frontal apotome with conspicuous finger-shaped tubercles (072g.jpg). Frontal warts large to small; cephalic tubercles absent (small in type material and in material from Wyoming and Sweden; large in material from Alberta, Montana, Alaska). Antennal sheath base without a sharp tooth. Thoracic horn 95, 105µm long (n=2), oval, shortly petiolate; ThR 1.9, 2.2 (n=2). Thoracic horn ellipsoid, dark to light brown, filled, stalked. Cephalothoracic setae weak and difficult to see. Precorneals short, about 1.5x as long as dorsocentrals, with light sockets; 1 median antepronotal, 0 lateral antepronotals, 0-4 dorsocentrals, weak; arrangement of dorsocentrals varies. Thorax dorsally granulose anteriorly and along eclosion line.
Abdomen: Length hook row II 0.22x width tergite II (n=1). Tergites I and II bare; II-V with central (apical) patch of recurved hooklets along posterior margin; patch on II almost 2x as large as other patches; VI, VII with patch of straight points along posterior margin; III-VIII with point patch anteriorly. Pedes spurii B on I-III; pedes spurii A on VI, VII. Sternites I and VIII bare; II-VI with central horizontal point patch anteriorly; VI with points along posterior margin; VI, VII with 2 off-center point patches anteriorly. Dorsal setae I-VIII: 4,5,5,5,5,5,5,1; Ventral setae I-VIII: 0,2,2,3,3,3,2,1; Lateral setae I-VIII: 1,2,3,3,3,3,4,3; Od setae I-VIII: 0,1,1,1,1,1,1,1.
Anal segment: Anal lobe greatly reduced, setae absent. Genital sheaths extended beyond lobe in male and female.

Species keys out at Page 843: Orthocladiinae 254 Orthocladius of the Text Key.

Holarctic species: widespread in Europe.
(For more information see module IdentifyIt – file: Orthocladiinae).

Ecological notes
Montane torrents and fast flowing streams.