The frontal antennae are slender and awl-shaped. The ceratophore of the middle antennae typically has 9-12 rings. The mandibles feature straight and tapered shafts. In the front margin of each of the initial 10 segments that bear gills, there is a dark spot. The gills have relatively long filaments organized into 6-10 whorls. The pseudocompound setae in the first few feet have hoods and are either single-toothed or have a small secondary tooth. The comb-like setae have 5-10 coarse teeth. In the parapodia of the branchial region, the presetal lobe is asymmetrical and includes an inferior projection. The acicular setae have two teeth.