Chironomus prasinus

Author: Meigen, 1804

Exuviae 10.9-13.7mm long (n=9).
Colour: Exuviae golden to golden-brown; comb of segment VIII golden to golden-brown; anal lobes evenly coloured or paler towards base.
Cephalothorax: Cephalic tubercles LxB 140x125-253x175µm (n=7). Frontal setae 63-100µm long (n=5). Basal ring of thoracic horn 183x75-283x115µm; tracheal patch 147x40-230x73µm; 16-24 tracheoles across (n=7); 2.5-3.0µm in diameter. Tracheal patch of thoracic horn without an "eye". At most thoracic granulation well-developed anteriorly, the granules small except for a band along suture of obviously larger granules; with or without a mid lateral patch, not reaching the suture dorsally.
Abdomen: Hook row II entire, length of row 0.60, 0.61x width tergite (n=2); hooks 83-100 (n=5). Armament of tergites II-VI not strongly waisted and with the posterior transverse band not successively increasing in extent to tergite VI; usually reduced on VI. Sternite I smooth or with a few scattered spinules. Shagreen of sternites III and IV forming a lateral longitudinal band on each side, which may spread inwards anteriorly. Pleura of segment IV spinulate or smooth. Comb of segment VIII with 10-18 elongate teeth (n=9), set on the end of an elongate ventral cuticular mound which exceeds appreciably the apico-lateral corner of the segment. Lateral taeniae of segments V-VIII: 4,4,3/4,4/5.
Anal segment: Fringe of anal lobe with 165-217 taeniae (n=9).
(Linked adult male: Langton and Pinder, 2003a)

Note: This form and Chironomus balatonicus have apparently inseparable pupae. See also note on colour under Chironomus nuditarsis.

Species keys out at Page 159: Chironomini 56 Chironomus of the Text Key.

Holarctic species: widespread in Europe (except Scandinavia).
(For more information see module IdentifyIt – file: Chironominae).

Ecological notes
Lakes, large rivers (slack water), brackish broads and hard water drains.