Diamesa modesta

Author: Serra-Tosio, 1967

Diagnosis (n=1)
Exuviae 4.1mm long.
Colour: Pale buff exuviae, almost colourless, with the colour pattern faintly picked out as in caucasica except for the strongly contrasting transverse golden band along the bases of the tooth rows, the brown teeth set on distinct golden mounds.
Cephalothorax: Frontal setae 105µm long. Thoracic horn 205µm long; ThR 15.8. Precorneal setae 2,3: 157; 150µm long.
Abdomen: Hook row II absent. Total dorsal teeth I-VIII 98 (25µm long). Total ventral teeth IV-VIII 52. Tergites II-IV behind posterior tooth rows with at most a few points. Shagreen points of tergite III 8µm long. Lateral margins of segments II-V strongly serrate. Relative length segments IX:VIII:VII = 1.0:0.52:0.85; relative width segments IX:VIII:VII = 1.0:1.3:1.6. Segment VIII narrow rectangular, 3.2x as wide as long; segment VII broad rectangular, 2.4x as wide as long (032c.jpg). Lateral setae 1-4 of segment III 80; 70; -- 83; 75µm long.
Anal segment: Dorsal points of tergite IX not spreading onto anal lobes. Anal lobe ratio 1.6. Each anal lobe with 3 macrosetae; length macrosetae 0.7x lobe length.
(Linked adult male: Langton and Pinder, 2003a)

Species keys out at Page 562: Diamesinae 38 Diamesa of the Text Key.

Central and western Europe and Middle Eastern alpine regions.
(For more information see module IdentifyIt – file: Other subfamilies).

Ecological notes
Cool streams and cold glacial torrents, 1,000-2,000m asl.