Heliotropium ovatum (Wall. ex G.Don) Rueangs. & Chantar., 2023

Rueangsawang, Kanokorn & Chantaranothai, Pranom, 2023, A taxonomic synopsis of Heliotropiaceae and new combinations in Heliotropium from Thailand, PhytoKeys 232, pp. 189-210 : 189

7. Heliotropium ovatum (Wall. ex G.Don) Rueangs. & Chantar. comb. nov.

Tournefortia ovata Wall. ex G.Don, Gen. Hist. 4: 369. 1837.

Type.

Myanmar, Rangoon, Wallich Numer. List 908 (holotype K [K001110253!]) .

Distribution.

India (Andaman Islands, Nicobar Islands), Myanmar, Thailand (Fig. 1L ).

Ecology.

Open or shaded, slightly disturbed area in mixed evergreen forest 400-500 m alt., flowering and fruiting from November to April.

Specimens examined.

Thailand, Northern : Chiang Rai, Tham Luang-Khun Nam Nang Norn NP, Mae Sai , 560 m alt., 27 Mar 2012, Norsaengsri & Tathana 9227 (QBG); Mae Tak, 3 Mar 1958, SØrensen et al. 1865 (BKF) ; Chiang Mai, Gnai, Tintok , 500 m alt., 8 Mar 1965, C.A. & B.S. 270 (BKF); Doi Chiang Dao, 750 m alt., 29 Mar 1995, Maxwell 95 - 269 (BKF); ibid., 575 m alt., 11 Mar 1989, Maxwell 89 - 317 (BKF, CMU, L); ibid., 550 m alt., 8 Mar 1965, Hambanond 270 (BK) ; Phayao, Doi Pha Dam, Rom Yen Subdistrict, Chiang Kham , 890 m alt., 21 Feb 2013, La-ongsri et al., 2662 (QBG) ; Lampang, Mae Pukaung , 6 Mar 1925, Winit 1282 (BK, K) ; Nan, Song Khwae, Nam Pan Village , 350 m alt., 12 Jan 2011, Srithi 630 (QBG) ; Tak, Lan Sang NP, 2 Jan 1969, Cheviwat & Nimanong 10 (BKF) ; Phrae, 500 m alt., 22 Mar 1913, Vanpruck 454 (BKF, K) ; Huai Rai, 13 Mar 1961, Chanthamuk 6 (BKF); ibid., 13 Mar 1961, Chanthamuk 9 (BKF); ibid., 23 Mar 1961, Phengklai 66 (BKF, C, K); 26 Jan 1913, Vanpruck 357 (BKF, K) ; Sukhothai, Srisatchanalai NP, route to Tad Dao Waterfall , 3 Feb 2015, Maknoi 7243 (QBG). North-eastern : Phetchabun, Nam Nao NP, 18 Feb 2014, Maknoi 6553 (QBG). Eastern : Nakhon Ratchasima, Bua Yai , 400 m alt., 29 Nov 1924, Kerr 9487 (BM, BK, E, K, L). South-western : Kanchanaburi, Si Sawat, Dongyai , 50 m alt., 17 Aug 1971, Phengklai et al. 3016 (BKF), ibid., 600 m alt., 17 Jan 1926, Kerr 10233 (BM, BK, K, E); Thung Yai Naresuan WS, Sangklaburi, 475 m alt., 11 Apr 1994, Maxwell 94 - 489 (CMUB, L) ; Prachuap Khiri Khan, Pran Buri , 25 Nov 1929, Put 2449 (BM, BK, K) .

Vernacular.

Liang (เหลียง).

Diagnostic characters.

Heliotropium ovatum is similar to H. biblianum in having ovate or ovate-lanceolate leaves, but differs in the 5-merous flower and densely minute tubercules on the lower leaf when dry (vs. 4-merous flowers and minute tubercules on both leaf surfaces in H. biblianum ).

Figures

Figure 1. Distribution of Heliotropiaceae from Thailand, based on the specimens examined.