Tanytarsus verralli

Author: Goetghebuer, 1928

Diagnosis (n=2)
Exuviae 4.5, 4.9mm long.
Cephalothorax: Cephalic tubercles short, broad conical. Frontal setae robust, 95µm long. Antennal sheath base with a rounded conical projection. Thoracic horn 490, 535µm long; ThR 17.8, 19.6. Posterior thoracic mound weak. Dorsocentral seta 4 robust, spine-like in appearance, 3µm to over 5µm in breadth near base, tapering from base to apex; 110µm long (140i.jpg). Wing sheaths rounded apically, pearl row absent.
Abdomen: Hooks of hook row II 106, 140. Tergites II-VI with paired anterior point patches; point patches on tergite II small rounded; point patches of tergites III-VI broad oval, of 6-10 longitudinal rows of points, the patch on IV less than three times as long as broad. Armament tergite IV strong, 85, 95µm long. ArR II-VI 0.42 : 0.89 : 1.0 : 0.89 : 0.89, 0.41 : 0.88 : 1.0 : 1.0 : 0.88. Comb of segment VIII on a flat extension of the corner of the segment, 35, 40µm wide; with 7/8, 5/6 marginal teeth. Lateral taeniae of segments IV-VIII: 0,1,3,4,4, taeniae well-developed.
Anal segment: Anal lobe ratio 1.48, 1.5. Fringe of anal lobe with 26/27, 26/26 taeniae, forming a complete series.
(Linked adult male: Langton and Pinder, 2003a)

Note: It is unlikely that the characters given will continue to separate verralli from Tanytarsus debilis (Meigen) and Tanytarsus Pe4c when more positively associated material is available as these specimens are probably extreme in the development of dorsocentral seta 4 and breadth of abdominal point patches. However, it seems likely that exuviae which have keyed out here are verralli.

Species keys out at Page 458: Tanytarsini 99 Tanytarsus of the Text Key.

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

Ecological notes
Lakes and ponds.