Phormosoma placenta Thomson, 1872 b— $ Mortensen 1927b: 25; Mortensen 1935: 125–135, figs. 80–82, pl. 1, figs. 1–5, pl. 2, figs. 1–19, pl. 74, figs. 1–6, 19; Marques 1980: 105; Benavides-Serrato et al. 2012: 53.
Type locality: about 100 miles to the north of the Butt of the Lewis, in Scottish waters (59°43’N, 7°40’W).
See: Thomson (1872b: 732–737, pl. 62, figs. 1–5, pl. 63, figs. 1–9, 9a); Mortensen (1935).
Occurrence: North Atlantic, in the Davis Strait (Mortensen 1903) south to the Northeast coast of USA (Koehler 1921a, H.L. Clark 1925) eastwards south of Iceland (Mortensen 1903) to Gulf of Guinea (Koehler 1909, Grieg 1932, Chesher 1966), including the Azores, Canary and Cape Verde archipelagos (Koehler 1909, Mortensen 1927b). The subspecies P. placenta sigsbey Agassiz, 1880 and P. placenta africana Mortensen, 1934 are reported from the Caribbean and South African waters, respectively (Mortensen 1935, Serafy & Fell 1985).
Depth: 215– 2,500 m (Mortensen 1935); AZO: 1,257 m (Mortensen 1927b).
Habitat: gregarious bottom-feeder (Serafy & Fell 1985) on soft sediments (muddy sand to soft ooze; Gage et al. 1985).
Larval stage: lecithotrophic (Emlet 1995).
Remarks: the record of Phormosoma placenta in the Azores is based on Mortensen (1927b) who identified this species among the material collected by Talisman (sta 127, 1883: 38°38’00”N, 28°20’46”W, 1,257 m).