Author: Serra-Tosio, 1964
Diagnosis (n=1, material in coll. Serra-Tosio)
Exuviae 4.1mm long.
Colour: Buff, with bright golden teeth (20µm long) set on a transverse golden-brown band; lateral margins of segments golden-brown.
Cephalothorax: Frontal setae 150µm long. Precorneal setae 2,3: 138; 120µm long. Lateral antepronotal seta as large as the lower median antepronotal seta. Thoracic horn 140µm long; ThR 10.8.
Abdomen: Hook row II absent. Posterior to tooth row on tergite VII there is a very narrow band of points of similar size to those on the tergite and further similar points spread inwards from the paratergite for a short distance, the conjunctive otherwise unarmed (032d.jpg) (N.B. ventrally this conjunctive is armed with minute points as in Diamesa laticauda). Total dorsal teeth I-VIII 98. Total ventral teeth IV-VIII 64. Abdomen with neat, more or less isodiametric reticulation, obvious on anterior tergites and paratergites, in general evanescing progressively posteriorly but extending at least to paratergite VI laterally. Shagreen points of tergites small, of tergite III 4µm long. Relative length segments IX:VIII:VII = 1.0:0.55:0.73; relative width segments IX:VIII:VII = 1.0:1.3:1.6. Segment VIII 2.8 and segment VII 2.7 times as wide as long. Lateral setae 1-4 of segment III 43; 53; -- 50; 30µm long.
Anal segment: Points of tergite IX not spreading to edge of anal lobes. Male genital sheaths without a mid-lateral invagination. Anal lobe ratio 1.7. Each anal lobe with 3 macrosetae; length macrosetae 0.7x lobe length.
Species keys out at Page 557: Diamesinae 33 Diamesa of the Text Key.
Distribution
N+C European alpine regions.
(For more information see module IdentifyIt – file: Other subfamilies).
Ecological notes
Cold montane brooks and glacial torrents at about 2,000m asl.