Tanytarsus signatus

Author: (van der Wulp, 1858)

Exuviae 2.9-5.1mm long (m=4.0mm, n=14).
Cephalothorax: Cephalic tubercles very shallow conical. Frontal setae 45-55µm long (n=5). Antennal sheaths with a small, short-conical swelling at base. Thoracic horn 315-515µm long (n=9); ThR 15.8-22.3 (n=5) (141f.jpg). Posterior thoracic mound weak, rounded. Wing sheaths rounded apically, pearl row absent.
Abdomen: Length hook row II 0.38x width tergite (n=1); hooks 85-99 (n=3). Armament of tergites III-VI on slightly yellowed patches. Point patches of tergite III longitudinally broad oval, less than one quarter the length of the segment, with a field of minute points spreading posteriorly from the point patches to the posterior end of the segment. Tergites IV and V with the armament arranged in longitudinal bands. Armament tergite IV strong, 38-53µm long (n=4). ArR III-VI 0.55-1.08 : 1.0 : 0.83-1.20 : 0.78-1.12 (n=13). Postero-lateral comb of segment VIII narrow, 17-35µm wide (n=10), truncate posteriorly; with 4-6 elongate marginal teeth (n=6). Lateral taeniae of segments V-VIII: 0(1),1,3(2,4),4.
Anal segment: Anal lobe ratio 1.24-1.56 (n=4). Fringe of anal lobe with 18-25 taeniae (m=22.1, n=14), forming a complete series.
(Linked adult male: Langton and Pinder, 2003a)

Species keys out at Page 464: Tanytarsini 105 Tanytarsus of the Text Key.

Holarctic species: widespread in Europe, north Africa.
(For more information see module IdentifyIt – file: Chironominae).

Ecological notes