Nilotanypus dubius

Author: (Meigen, 1804)

Exuviae 2.4-2.9mm long (m=2.7mm, n=12) (019-1.jpg).
Cephalothorax: Thoracic horn 170-215µm long (m=191µm, n=12); ThR 3.6-4.5 (m=3.9, n=8). Plastron plate large, 105-135x35-60µm (n=11), offset apically, occupying over half the horn's length, without rim (019b.jpg). Thorax comb with 10-14 teeth. Thorax shagreened.
Abdomen: Tergites II-VII with the points becoming larger posteriorly to form an obvious transverse band of granules in three or four rows; tergite VIII with a transverse row of teeth on its posterior margin. Segment VII with one lateral taenia, VIII with five.
Anal segment: Anal lobes tapered, smooth and buckled inwards apically producing a variable and low anal lobe ratio (019c.jpg). Anal lobe ratio 1.3-2.3 (m=2.1, n=12).
(Linked adult male: Langton and Pinder, 2003a)

Species keys out at Page 75: Tanypodinae 61 Nilotanypus of the Text Key.

Widespread in Europe and circum-Mediterranean.
(For more information see module IdentifyIt – file: Other subfamilies).

Ecological notes
Fast flowing streams; also rivers and northern lakes.
Predominantly in slowflowing sections with grayling and barbel (Janecek, 1999a).