Strenzke, 1959
Body
Living larvae are red. Four ventral tubules on the 11th abdominal segment of equal length and 1 pair of lateral tubules on segment 10. Procercus and anal tubules present (Wiederholm, 1983; Vallenduuk and Moller Pillot, 2002).
Head
The frontal apotome is light and the gula is pale (Vallenduuk and Moller Pillot, 2002).
Antenna
The antenna consists of 5 segments. The blade is not longer than the flagellum. Lauterborn organs distally on the second segment.
Mentum
The mentum has three median teeth and 6 pairs of lateral teeth. Mentum size (see glossary) is 48 - 52 µm. Mentum type 1 Mentum type 1 pict. Ventromental plates with 40 - 47 striae and 21 - 30 outer hooks (Vallenduuk and Moller Pillot, 2002).
Labrum
SI is plumose and labral lamellae are normal.
Mandible
The mandible with a pale dorsal tooth, apical tooth dark and 3 inner teeth. The inmost tooth as dark as the other teeth (type3) Chiron mand lll9. The pecten mandibularis is present and seta interna with 4 toothed and plumose branches.
Differential characteristics
Chironomus is the only genus with 2 pairs of tubules on the 11th segment Chir 4 ventral tubules. Some species lack the ventral tubules (C. salinarius Chir no tubules, C, nudiventris and C. agilis). C. salinarius occurs only in brackish and salt water. The latter two species have a pair of lateral setae on segment 10 Chir 2 lateral tubules. These two species can be separated from Einfeldia pagana by the absence of a pit on the frontal apotome.
C. crassimanus can be separated from all other Chironomus by:
Two pairs of ventral tubules on segment 11 and 1 pair of tubules on segment 10.
Gula light, frontoclypeus light and inner tooth of the mandible as dark as the other teeth.