Astropecten sphenoplax Bell, 1892 — $ Koehler 1909: 42, pl. 17, fig. 8; Mortensen 1927a: 59; Cherbonnier & Sibuet 1972: 374;
Persephonaster humilis (Koehler, 1907a) — $ Koehler 1909: 61–62, pl. 19, figs. 2–4; Mortensen 1927a: 64;
Persephonaster sphenoplax (Bell, 1892) — $ A.M. Clark & Downey 1992: 65–66, figs. 14e, f. h–j, I, 15i, j, pl. 20, figs. A–C; García-Diez et al. 2005: 46.
Type locality: NW of Ireland.
See: A.M. Clark & Downey (1992).
Occurrence: Northeast Atlantic, from the Rockall Trough (A.M. Clark & Downey 1992) to the northern part of the Bay of Biscay (Cherbonnier & Sibuet 1972) and in the Azores (Koehler 1909); possibly also in the SE of Florida (A.M. Clark & Downey 1992).
Depth: (?675)820– 1,187 m (AZO: 845– 1,187 m; Koehler 1909, A.M. Clark & Downey 1992).
Habitat: soft to hard substrates (Koehler 1909).
Remarks: A.M. Clark & Downey (1992) remarked that Bell’s incomplete original descriptions might have led Koehler (1909) to fail to recognise Persephonaster sphenoplax in the Azorean material he used to erect Persephonaster humilis. The former authors compared material belonging to both species and concluded them to be conspecific, dismissing morphological differences as size-related.