Thienemann, 1934
Body
Medium sized larvae up to 7 mm long. Living larvae are yellowish sometimes with a brown thorax (Moller Pillot, 1984b). The abdomen lacks hairs. The anterior parapods are fused, bearing no claws. The two posterior parapods are undivided. The posterior parapods and anal tubules can be retracted into the anal body segments. These segments are at a right angle with the body. The procercus is absent Bryoph gr muscicola anal segm.
Head
The head length is up to 0.4 mm in some Dutch larvae (Moller Pillot, 1984b).
Antenna
The antenna consists of five segments. Sometimes the third segment is shorter than the fourth. The blade is usually shorter than the flagellum Bryoph gr muscicola antenna, sometimes longer.
Mentum
The mentum has one or two large median and 4 pairs of lateral teeth Bryoph gr muscicola mentum. The ventromental plates are conspicuous but cover only the basal part of the outer teeth. The beard is absent.
Labrum
The pecten epipharyngis consists of three scales, SI is simpel and the premandible with three teeth (Wiederholm, 1983).
Mandible
The mandible with a distal tooth and 3 smaller teeth within. The seta interna is absent (Wiederholm, 1983).
Differential characteristics
The right angle between the anal segment and the body axis Bryoph gr muscicola anal segm is distinctive for Bryophaenocladius and Gymnometriocnemus. Wiederholm (1983a) separates these genera by undivided posterior parapods in Bryophaenocladius and divided parapods in Gymnometriocnemus. Also anal tubules present in Bryophaenocladius and absent or vestigial in Gymnometriocnemus.
Diversity
European species: 21
Treated species: 0