Ilanga laevissima (Martens, 1881)

Trochus laevissimus Martens, 1881: 65 . Type loc.: 33°59ʹS: 17°51ʹE, 50 fathoms [ca 55 km west of Table Bay, 91 m]; holotype in ZMB (129315).

Minolia (Nachaeroplax) congener G.B. Sowerby (III), 1903: 223, pl. 5, fig. 2. Type loc.: Cape Infanta bearing N 1/4W; distant 82 miles; depth, 40 fathoms [73 m]; one syntype in SAMC (A5257), figured by Herbert (1987: figs 34–36), two syntypes in NHM (NHMUK 1903.7.27.67–8).

Minolia laevissima —G.B. Sowerby (III), 1903: 231, pl. 5, fig. 1.

Solariella laevissima — Martens, 1904: 49, pl. 5, fig. 2. E.A. Smith, 1906: 56. Barnard, 1963a: 239, fig. 10c. Kensley, 1973: 42, fig. 103.

Solariella congener — E.A. Smith, 1906: 55.

Solariella nitens Thiele, 1925: 14 [48], pl. 1[13], fig. 16. Type loc.: Valdivia St’n 113, SW of Cape Point (34°33.3ʹS: 18°21.2ʹE), 318 m; three syntypes in ZMB.

Ilanga laevissima — Herbert, 1987c: 310, figs 1–3, 6, 34–50 (detailed synonymy and chresonymy). Williams et al., 2013: 9.

Distribution. Southern Mozambique to W. Cape (off Table Bay); 40–350 m (living 55–270 m).

Notes. Molecular sequence data has demonstrated that the material studied by Barnard (1963a) and Herbert (1987c) is composite, containing at least one additional cryptic species (Williams et al. 2013). Further studies are needed to resolve the taxonomy of this complex.