Author: Kownacki and Kownacka, 1973
Diagnosis (n=2, unless stated otherwise, material in coll. Kownacki)
Exuviae 5.5, 5.9mm long (n=2).
Cephalothorax: Frontal setae 320µm long (n=1). Thoracic horn 500, 510µm long; ThR 22, 28. Precorneal setae 1-3: 85, 100; 250, 300; 225, 250µm long. Thorax granulate.
Abdomen: Rarely less than 7 teeth in tooth row of tergite II. Segments VI and VII dorsally each with 4-10 teeth. Total dorsal teeth II-VIII 59, 60; best developed dorsal teeth about 100µm long, golden to brown. Total ventral teeth III-VIII 74, 97+. Armament of tergite II consists of dense points extending at least for half the width of the tergite and posteriorly at least as far as the anterior adhesion marks. Shagreen points of tergite III 8, 10µm long. Behind the tooth rows there is a band of points; points of tergites III-VII spreading posteriorly outside the anterior adhesion marks, extending the point patch towards the postero-lateral corner, progressively more extensive on succeeding segments (031d.jpg). Relative length segments IX:VIII:VII = 1.0:0.60, 0.65:0.79, 0.91; relative width segments IX:VIII:VII = 1.0:1.2, 1.3:1.47, 1.5. Segment VIII 2.8, 3.0 and segment VII 2.4-2.6 times as wide as long. Lateral setae of segments II-VII long; setae 1-4 of segment III 150; 140, 155; -- 155, 180; 125, 150µm long.
Note: In deeply golden examples, paratergites of the same colour and intensity as the background colour of the tergites, the lateral margin narrowly tinged with yellow; in pale examples the tergites are distinctly brown except for small colourless areas. Thoracic setae and lateral abdominal setae grey.
Anal segment: Anal lobe ratio 1.3-1.4. Each anal lobe with 3 macrosetae; length macrosetae 0.7-0.8x lobe length.
Species keys out at Page 582: Diamesinae 58 Diamesa of the Text Key.
Distribution and Ecological notes
Originally described from the Caucasian mountains (glacial stream, 1,700m asl.), it is also found in the Tatra mountains, the Austrian and Italian Alps, Lebanon and Turkey.
(For more information see module IdentifyIt – file: Other subfamilies).