(Edwards, 1929)
Subgenus Caulochironomus
Body
Medium sized tot large larvae, up to 10.5 mm. No tubules present on the 11th segment (Vallenduuk, 1999).
Head
Length 550 - 650 µm. The head capsule is shining. Anterior margin of fronto-clypeal apotome concave. Both labral sclerites 1 and 2 are present. Sclerite 1 is arch shaped (sg. Caulochironomus Caulochir frontoclypeus. Frontal apotome is widened medially, 1.8 x longer than wide, without dark band along the border (Vallenduuk, 1999).
Antenna
The antenna consists of 5 segments. The blade is shorter than the flagellum. Lauterborn organs distally on the second segment.
Mentum
The mentum has a single median tooth with 6 pairs of lateral teeth. The 4th lateral is reduced Glypt mancun ment. The ventromental plates are 6.5 x wider than high.
Labrum
SI is plumose to toothed on both sides and labral lamellae are a toothed plate. The pecten epipharyngis with many unequal distal teeth and small points on the surface. The premandible has two apical teeth.
Mandible
The mandible with a dorsal tooth, one apical tooth and 3 inner teeth. The pecten mandibularis is present and seta interna with 4 toothed and plumose branches. The seta subdentalis (SSD) is longer (17 - 22 µm) than the width of the inner mandibular tooth Glyp manc SSD pict 8 (Wiederholm, 1983; Vallenduuk, 1999).
Differential characteristics
The combination of dull headcapsule, simpel mid-mental tooth and 6 pairs of lateral teeth Glyp mentum are distinctive for subgenus Glyptotendipes. Subgenus Caulochironomus can be identified by shining headcapsule, frontoclypeal apotome with concave anterior margin, labral sclerites 1 and 2 present Caulochir frontoclypeus and three inner mandibular teeth. In subgenus Trichotendipes the combination of a subapical pit on the frontal apotome and clypeus separate from frontal apotome Glyp signatus frontoclypeus is distinctive.
G. mancunianus can be separated from the other species of subgenus Caulochironomus (except G. viridis) by the mentum with single median tooth and 6 pairs of lateral teeth with the 4th lateral reduced.
G. mancunianus can be separated from G. viridis by the SSD longer than the width of the inner mandibular tooth. Also the frontal apotome is 1.8 x longer than wide (2.5 x in G. viridis) and the ventromental plates are 6.5 x wider than high (5 x in G. viridis).