Holmgren, 1869
Body
Small to medium sized larvae. Living larvae may have pink stains (Smittia gr. aquatilis, Moller Pillot, 1984b). The anterior parapods are fused basally. The posterior parapods are separate or reduced Smittia gr aquatilis anal segm8, Moller Pillot, 1984b) bearing a row of claws. The procercus is absent and two pairs of reduced anal tubules are present (Wiederholm, 1983; Moller Pillot, 1984b).
Head
Antenna
The antenna consists of five segments. Segment 2 is as long or longer than segment 1. Segments 3-5 are reduced. The blade is shorter than the flagellum. Lauterborn organs are present Smittia gr aquatilis antenna.
Mentum
The mentum has one broad median tooth and 5 pairs of lateral teeth. The ventromental plates are weak. The beard is absent Smittia gr aquatilis mentum.
Labrum
The SI is plumose and the premandible has two apical teeth (Wiederholm, 1983; Moller Pillot, 1984b).
Mandible
The mandible has an apical tooth and 3 inner teeth. The seta interna has serrate branches (Wiederholm, 1983).
Differential characteristics
The combination of procercus absent Smittia gr aquatilis anal segm8 and SI plumose separate Smittia from all other Orthocladiinae except Clunio which lives at the seacoast and lacks anal tubules.
Diversity
European species: 25
Treated species: 0