SESUVIUM MESEMBRYANTHEMOIDES Wawra in Wawra & Peyr., Sitzungsber. Kaiserl. Acad. Wien, Math.- Nat. 38: 564. 1860.

Halimus [Halimum] mesembrianthemoides (Wawra & Peyr.) Hiern, Cat. Afric. Pl. (Hiern) 1(2): 413. 1898.— TYPE: ANGOLA. Wawra 210 (Type not found, possibly destroyed in B or W). Mossamedes, sea-shore, 01 Jul 1859, Welwitsch 2389 (lectotype: LISU 214652 digital image!, designated here; isolectotypes: BM, BR, C 10005289 digital image!, COI, K!).

Sesuoium crystallinum Welw. ex Oliv., Fl. Trop. Afr. [Oliver et al.] 2: 586. 1871.— TYPE: ANGOLA. Mossamedes, sea-shore, 01 Jul 1859, Welwitsch 2389 (holotype: LISU 214652 digital image!, isotypes: BM, BR, C 10005289 digital image!, COI, K!)

Creeping perennial herb with a deep taproot; bladder cells bulging and globose, covering shoots, leaves and outside of flowers; whitish when dry; internodes terete and succulent. Leaves 10–30 mm long, elliptic to oblong, up to 3 mm wide (when dry), subterete, and subsessile. Bracts in 2–4 pairs, large (up to 5 mm long), lanceolate to triangular; dark in color when dry. Flowers 10–13 mm long, subsessile, pink to violet. Stamens numerous. Ovary with 3–5 carpels. Fruit a many-seeded capsule (according to descriptions). Seeds not seen, described to be black and smooth.

Notes — C 4 species (Bohley et al. 2015). The outermost pair of bracts sometimes shows a loose cover of small bladder cells along the midvein.

Sesuoium mesembryanthoides Welw., nomen nudum, Apont: 557. 1859, has been assigned to S. crithmoides by previous authors, e.g. Gonçalves (1970) in Conspectus Florae Angolensis.

Distribution and Habitat — Angola, Namibia, apparently also in Syria (Fig. 5C). The species grows on sand (beaches, dunes) in coastal areas.

Representative specimens examined — ANGOLA. Cabo Negro, sand dunes, 15°40′S, 11°59′E, 5 m, 15 Apr 1973, P. Bamps et al. 4519 (K); Mossamedes, 1859, Welwitsch 2387 (K); Lobito Bay, near Benguella, 12°36′16.1676″S, 13°21′39.9312″E, 01 Sep 1906, H. Bolus 12453 (BOL); Coroca Valley near Namibe, ca. 15°10′09.2424″S, 12°09′28.5012″E, Nov 1931, O. Jessen 337 (B).

SYRIA. Sur la piste d’ Akra á Khan Abou Chamat (desert du Syrie), 27 Mar 1931, R. Gombault 1998 (P, P04583848 digital image); Palmyra (desert du Syrie), 3 Apr 1934, R. Gombault 3468 (P, digital image, P04583849).