Genus Aphelochaeta Blake, 1991

Type species: Tharyx monilaris Hartman, 1960 . Original designation by Blake (1991).

Diagnosis (after Blake, 2018). Prostomium conical to rounded; peristomium elongate with pair of grooved dorsal tentacles arising either on peristomium or anterior to setiger 1. Anterior segments often expanded, crowded or uncrowded; abdominal segments sometimes beaded or moniliform in appearance; setae simple capillaries lacking distinct serrations using light microscopy, but distinct fibrils may be visible using SEM; posterior end frequently expanded, tapering to a simple pygidial lobe.

Remarks. To date, only ten valid species of Aphelochaeta have been reported from abyssal depths of about 3000 m and greater (Blake, 2018, 2019). In the present study, two new species have been identified in the samples from off the Australian east coast. Others are most certainly present, but the available specimens are either too fragmented or damaged to characterize.