Protoariciella Hartmann-Schröder, 1962: 133–134.
Diagnosis. Prostomium rounded, 2 eyes present or absent; two achaetous peristomial segments; branchiae from chaetiger 5–8, can be absent in posteriormost segments; notopodia with crenulated capillaries; forked chaetae, subuluncini and acicular chaetae present or absent; neuropodia with crenulated capillaries and serrated or smooth uncini.
Remarks. Blake (2017) supposed that due to their small size (<10 mm) all Protoariciella species are likely juveniles of Leodamas or Naineris. In addition, he described Naineris antarctica Blake, 2017, which is very similar to Protoariciella. In fact, a worm identified as P. uncinata has been shown to be a juvenile of Leodamas tribulosus (Bleidorn et al. 2009). Phylogenetic molecular investigations are required to confirm or disprove this statement for other Protoariciella species. At least for Protoariciella oligobranchia, the presence of eggs was reported (Hobson 1976). Protoariciella is accepted as a valid genus here.