Tanytarsus excavatus

Author: Edwards, 1929

Diagnosis (Reared material leg. X.-F. Garcia)
Exuviae 3.9-4.4mm long (n=7).
Cephalothorax: Cephalic tubercles broad shallow cones. Frontal setae 88, 100µm long (n=2). Antennal sheath base with a rounded conical swelling. Thoracic horn without spinules; horn 430-568µm long (n=4); ThR 14.3-22.0 (n=3). Posterior thoracic mound weak, rounded. Wing sheaths rounded apically, pearl row absent.
Abdomen: Length hook row II 0.30-0.36x width tergite; hooks 74-90 (n=4). 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; tergite III unarmed behind the point patches. Tergites III-VI with the armament arranged in longitudinal bands. Armament tergite IV strong, 80-93µm long (n=7). ArR III-VI 0.54-0.92 : 1.0 : 0.90-1.0 : 0.66-1.0 (n=7). Postero-lateral comb of segment VIII 25-38µm wide, truncate posteriorly; with 6-9 elongate marginal teeth (n=5). Lateral taeniae of segments V-VIII: 1,3,3,4.
Anal segment: Anal lobe ratio 1.27-1.33 (n=4). Fringe of anal lobe with 22-28 taeniae (n=7), forming a complete series.
(Linked adult male: Langton and Pinder, 2003a)

Note: This species is very like the exuviae of Tanytarsus verralli, but in the place of the anterior point patches of tergite II there is at most a few scattered larger points amongst the shagreen.

Species keys out at Page 465: Tanytarsini 106 Tanytarsus of the Text Key.

Widespread in Europe.
(For more information see module IdentifyIt – file: Chironominae).

Ecological notes
Korttenoja, Finland.