Bathyactis symmetrica. — Moseley, 1881: 186–190 (in part: Challenger 299), pl. 11, figs. 1–5.
Bathyactis marenzelleri. Vaughan, 1906: 66, pl. 4, figs. 1a–b.
Fungiacyathus symmetricus. — Squires, 1969: 17, pl. 6, map 2. — Cairns, 1982: 5–7, pl. 1, figs. 1– 2, 8, map 1); 1994: 15–16, pl. 1a–f (synonymy, description). — Piñón, 1999: 19, 79 (listed).
Remarks. — Fungiacyathus marenzelleri is known from only two records off Chile: the abyssal plain off Valparaiso (33°S) at 2514 m (Moseley 1881 as B. symmetricus from Challenger 299) and the Chile Rise off Valdivia (41°S) at 3639 m (Cairns 1982). It is also known from many localities in the eastern Pacific from Peru to the Aleutian Islands, summarized by Cairns (1994). It is the deepest living scleractinian known, having a bathymetric range of 300–6328 m (Cairns 1982, Keller 1976) and is cosmopolitan in distribution. It is a freeliving, discoidal, extremely fragile solitary coral having 48 septa, all of which are obscured with abundant tissue when the coral is alive. The species is adequately described and illustrated by Cairns (1982, 1995).