Gelidium sanyaense G.C.Wang & X.L.Wang (Fig. 5)

Type: — CHINA. Xiaodonghai, Sanya, Hainan Island, intertidal, 18°11’95’’N; 109°29’48’’E, 15 March 2015, X. L.Wang, holotype SY 28- 1 in the Marine Biological Museum, Chinese Academy of Sciences (Qingdao) .

Vegetative structure: —Thalli were purple-red, 0.8–1.2 cm high (Fig. 5a). The prostrate stolons were terete, erect axes upward and compact short brush-like haptera. The erect axes were compressed, percurrent and lanceolate, with a width of 190–320 µm. Thalli had simple or one to two orders irregularly branches. It has a rounded apical cell (Fig. 5b). Cross-sections of the main axes showed a fusiform outline, consisting of 2–3 layers of cortical cells and 3 layers of medullar cells (Fig. 5c–d). Cortical cells were round 5–9.5 µm in width and medullary cells were elliptical 12–15 µm in width. Internal rhizoidal filaments abundant in the medulla. Reproductive structures not found.

Distribution and Habitat:—La Entrega, Oaxaca to Las Gatas, Guerrero. Intertidal rocks, with low incidence of light and high waves.

Material examined:— MEXICO. Guerrero, Las Gatas, intertidal, 17°37’13’’N, 101°33’10.88’’W, 09 January 2017, D. Rodríguez & I . Ruiz, 10892, 10893 (FCME). Oaxaca, La Entrega, intertidal, 15°45’11.91’’N; 96°48’48.26’’W, 8 June 2018, N . Quiroz-González, 10894, 10895 (FCME).