Small larvae, up to 4 mm long.
Antenna with perhaps always 6 segments; although P. coronata has only 5 visible segments; segment 6, if present, vestigial and may be overlooked; segment 3 shorter than the fourth. Blade extending at least to apex of segment 3. Lauterborn organs weak or absent. Style strong.
Labrum with SI with variable numbers of branches (always 3 or more?); remaining S setae simple. Weak labral lamellae may be present. Pecten epipharyngis consisting of 3 subequal scales. Up to 7 pairs of chaetulae laterales present. Premandible with 1-2 apical teeth and broad inner tooth; brush absent.
Apical tooth subequal to or longer than combined width of 3 inner teeth. Seta subdentalis present. Seta interna with 6-7 plumose branches.
Mentum with 1-2 (P. gracillima) median teeth; first of 6 pairs of lateral teeth often closely appressed to median tooth; only 5 pairs of lateral teeth in P. gracillima but median area may be worn. Ventromental plate distinct but only extending beyond outer tooth of flattened mentum in P. nigra; beard present in some unreared larvae tentatively assigned to this genus but absent in all reared species.
Maxilla palpiger normal with few lamellae at base. Galea without lamellae or pecten galearis. Seta maxillaris simple and fine. Appendix seta not visible.
Body with normal parapods, separate and bearing claws. Procercus about as high as wide; 6-7 anal setae present; lateral seta of procercus weak. Anal tubules distinctively shaped, conical, tapering to a point and shorter than posterior parapods. Some simple setae up to 50 micrometers long, may be present on the body.
Larval Parakiefferiella are found in all kinds of water bodies from flowing to standing, and including springs, and even some saline influenced bodies. The genus is found in all biogeographic regions, with verified records scarce for the neotropical.