2. Heliotropium foertherianum Diane & Hilger, Bot. Jahrb. Syst. 125(1): 46. 2003.

Fig. 4A-C

Tournefortia argentea L.f., Suppl. Pl.: 133. 1781. Type: Sri Lanka, Köenig s.n. (holotype BM [BM001014452 image!]).

Messerschmidia argentea (L.f.) I.M.Johnst., J. Arnold Arbor. 16: 164. 1935.

Argusia argentea (L.f.) Heine, Fl. Nouv.- Calédonie & Dépend . 7: 109. 1976.

Type.

Based on Tournefortia argentea L.f.

Distribution.

China (Hainan), Taiwan, Japan (Ryukyu), Vietnam, Thailand (Fig. 1G), Malesia, New Guinea, Australia.

Ecology.

Sandy beaches, flowering and fruiting from November to February.

Specimens examined.

Thailand, Peninsular: Surat Thani, Ban Bua Put, Ko Samui, 14 May 1928, Kerr 15728 (BK, E, K, TCD); Phangnga, Similan NP, 14 Nov 1996, Santisuk s.n. (BKF); Krabi, Lan Ta NP, 7 Jan 1992, Niyomdham 2854 (BKF); Ko Lan Ta Yai, 20 Mar 1998, Chamchumroon 37 (BKF); Satun, Adang, La-ngu, 15 Jan 1928, Kerr 14095 (BK, K) .

Vernacular.

Nguang chang thale (งวงช้างทะเล).

Diagnostic characters.

Heliotropium foertherianum is recognised by the combination of a small tree, oblanceolate or obovate leaves that are up to 20 cm long and have densely greyish tomentose hairs, subcorymbose inflorescence with peduncles up to 8 cm long, corollas as long as the calyx and fleshy fruits with a fleshy mesocarp and spongy endocarp.