Diamesa steinboecki

Author: Goetghebuer, 1933

Diagnosis (n=5, unless stated otherwise, material in coll. Serra-Tosio)
Exuviae 3.9-4.2mm long.
Colour: Pale buff exuviae with the background colour becoming more intense posteriorly. Anterior margin of abdominal tergites marked by a broad brown band just posterior to the colourless anterior transverse apodeme. The lateral margins of the segments, and dorsal and ventral lateral adhesion marks brownish; as a result, in well-marked individuals there are three distinct lateral longitudinal brown stripes.
Cephalothorax: Frontal setae 20-35µm long (n=4). Precorneal setae 2,3: 60, 65; 60, 65µm long (n=2).
Abdomen: Hook row II absent. Total dorsal teeth I-VIII 81-116 (029g.jpg); total ventral teeth IV-VIII 59-84. Points of tergite III 2.5µm long. Relative length IX:VIII:VII = 1.0:0.38-0.5:0.54-0.63 (n=3); relative width segments IX:VIII:VII = 1.0:1.1-1.2:1.25-1.3 (n=3). Lateral setae 1-4 of segment III 25-30, 40-52 -- 20-45, 25-50µm long.
Anal segment: Anal lobe ratio 1.5-2.0 (n=3). Each anal lobe with 3 macrosetae; length macrosetae 0.3-0.4x lobe length (n=4) (029h.jpg).

Species keys out at Page 551: Diamesinae 27 Diamesa of the Text Key.

Distribution
Palaearctic species: widespread European alpine regions.
(For more information see module IdentifyIt – file: Other subfamilies).

Ecological notes
Glacier brooks and torrents, generally between 2,000 and 3,000m asl.; Alps.

%LABEL% (%SOURCE%)