Tokunagaia rectangularis

Author: (Goetghebuer, 1940)

Diagnosis (Material in coll. ZMBN; in part after Halvorsen and Saether, 1987a - in italics)
Exuviae 3.1-3.9mm long (m=3.6mm, n=6).
Colour: Pale exuviae: brownish with slightly darkened posterior bands to the abdominal segments.
Cephalothorax: Frontal setae and warts absent. Antennal sheath with weak pearl row distal to pedicel, pearls stronger on inner margin. Ocular field with 1 postorbital. Thoracic horn absent. Median antepronotal setae 1,2: 48-58; 50-65µm long (n=3); precorneal setae 1-3: 30-60; 50-65; 30-50µm long (n=4); dorsocentral setae 1-4: 33-55; 40; 25-30; 28-40µm long (n=3). Wing sheaths without pearl row.
Abdomen: Segments II-VIII dorsally nearly covered with small points except for the adhesion marks. Hook rows on tergites continuous; hooks III 35-48, IV 36-47, V 25-38 (n=6). Tergite III with the median points about as large and as dense as those around, gradually diminishing in size laterally to the adhesion marks; the small anterior points grouped in horizontal rows spread posteriorly into the point patch half-way to setae D1; posterior transverse band of distinctly enlarged points two points deep; longest about 5µm long, about twice as long as broad at base, i.e. distinctly elongate (050a.jpg). Posterior teeth III 13-15, IV 13-18µm long (n=6). Pedes spurii A and B absent. Longest lateral setae VIII 38, 53µm long (n=2).
Anal segment: Anal lobe ratio 1.4-1.9 (n=4). Anal lobes without fringe. Anal macrosetae 0.7-0.9x length of the anal lobe (n=5). Male genital sheaths extend half way along the anal macrosetae.

Species keys out at Page 698: Orthocladiinae 110 Tokunagaia of the Text Key.

Palaearctic species: north and central Europe.
(For more information see module IdentifyIt – file: Orthocladiinae).

Ecological notes
Montane and far northern spring swamps and rivers.