Small larvae, up to 3 mm long. Head capsule light brown, occipital margin dark.
Antenna with 5 segments; segment 2 short and broad, 3rd and 4th subequal, 5th smaller. Ring organ on basal 1.3 of segment. Blade extending to 4th antennal segment. Lauterborn organs as large or longer than 3rd antennal segment.
Labrum with SI long and bifid, apparently arising on a common plate, other S setae simple. Weakly chitinised labral lamellae. Pecten epipharyngis of 3 subequal spines;. 6 pairs of simple chaetulae laterales. Premandible with 1 apical tooth; brush absent.
Mandible with apical tooth shorter than combined width of 3 inner teeth. Seta subdentalis broad. Seta interna multibranched.
Mentum with 1 median tooth and 6 pairs of lateral teeth, steeply declining in size laterally. Ventromental plate long, extending laterally with pointed apex; no beard.
Maxilla with small palp; chaetulae of palpiger large and leaf-like, with striae on dorsal side, lamellae of galea on dorsal side; without pecten galearis; seta maxillaris simple, lacinial chaetae and antaxial seta large.
Body with parapods divided, with simple claws. Procercus about as high as wide (long as wide) large, with strong anal setae present; anal tubules long and blunt.
Larvae and pupae have been found in stony runs of three South African rivers, the Mooi and Klein Mooi in KwaZulu Natal and the Dutoitskloof in Western Cape.