4. Euploca paniculata (R.Br.) M.W.Frohl. & M.W.Chase, Phytotaxa 434(1): 18. 2020.

Fig. 3A-C

Heliotropium paniculatum R.Br., Prodr. Fl. Nov. Holland.: 494. 1810. Type: Australia, Queensland: Sweer`s lsland, 28 Nov 1802, Brown 2930 (lectotype, designated by Craven 1996, p. 561: BM [BM001040573!]; isolectotype: K [K000998298!]).

Heliotropium tenunifolium var. paniculatum (R.Br.) Domin, Biblioth. Bot. 89: 549. 1928.

Heliotropium zeylanicum subsp. paniculatum (R.Br.) Kazmi, J. Arnold Arbor. 51: 156. 1970.

Type.

Based on Heliotropium paniculatum R.Br.

Distribution.

Pakistan, India, Myanmar, Thailand (Fig. 1D), Cambodia, Australia.

Ecology.

Open area of bare rock in dry dipterocarp and dry open deciduous forests, roadsides or wheat field; 50-1,000 m alt., flowering and fruiting from June to December.

Specimens examined.

Thailand, Northern: Chiang Mai, 300 m alt., 19 Jan 1914, Kerr 3291 (BM, K); Tak, Ban Tak, 150 m alt., 1 Sept 2016, Pooma & Pattharahirantricin 7944 (BKF); Nakhon Sawan, 31 km north, 100 m alt., 2 June 1959, Smitinand 5815 (BKF); Ban Dong Lan, Wang Jan, Sam Ngao, 28 Aug 2010, Norsaengsri 7030 (QBG); Lamphun, Phra Puttabat Tak Pa, 24 Aug 2010, Norsaengsri 7205 (QBG). North-eastern: Udon Thani, Ban Phen, 24 Dec 1964, Chermsirivathana 225 (BK); Sakon Nakhon, Phu Phan NP, 400 m alt., 6 Aug 2004, Nielsen et al. 1542 (BKF); Bueng Kan, Ban Tong, Seka, 220 m alt., 20 May 2004, Pooma et al. 4116 (BKF); Tham Noi waterfall, 320 m alt., 30 July 2008, Pooma et al. 7345 (BKF); Khon Kaen, Mueang Phon, 200 m alt., 5 July 1967, Smitinand 12385 (BKF). Eastern: Chaiyaphum, Pa Khok Yai Chiu, 190 m alt., 28 Aug 1966, S.N. 235 (BKF); Nong Bua Deng, 400 m alt., 15 Aug 1972, Larsen et al. 31869 (AAU, BKF, E, K); Nakhon Ratchasima, Bannot Phattana, Road 226, km 42-41, 14 Sept 2004, Pooma et al. 4677 (AAU, BKF, E); Phimai, 200 m alt., 26 Aug 1958, Smitinand 4783 (BKF); ibid., 5 Aug 1968, Pradit 316 (BK); Bua Yai, 200 m alt., 19 May 1931, Kerr 20488 (ABD, BK, BKF, BM, K, L); Ban Chum Seng, 22 May 1929, Noe 153 (BM, E, K); Surin, Chumphon Buri, 8 June 1982, Paisooksantivatana & Sutheesorn y 913 - 82 (BK); Roi Et, Kaset Wisai, 150 m alt., 22 June 1969, Simtinand & Nalamphun 10719 (BKF); ibid., 9 June 1982, Paisooksantivatana & Sangkhachand y1000 - 82 (BK); Ubon Ratchathani, Khua Nangnee waterfall, Pha Taem NP, 200 m alt., 22 Aug 2001, Pooma et al. 2281 (BKF), Phu Chong Nayoi NP, 20 Oct 2009, Middleton et al. 5196 (BKF, E, K); ibid., 250 m alt., 20 May 1998, Suksathan 1043 (QBG) ibid., 100 m alt., 25 Jan 1924, Kerr 8345 (BK, BM, K). South-western: Kanchanaburi, Khao Meng, 14 Apr 1965, Chantanamuck 1067 (BK); 50 m alt., 13 Sept 1931, Kerr 20552 (BK, BM, E, K, L); ibid., 50 m alt., 13 Sept 1931, Kerr 20553 (E, L); Prachinburi, Huai Saai, Cha-am, 19 Aug 2003, Puudjaa 1222 (BKF); Wat Luke Chang, Luke Chang Village, Tha Mai Ruak Subdistrict, Tha Yang, 5 July 2007, Maxwell 07 - 410 (QBG); Prachuap Khiri Khan, Hua Hin, 31 July 1976, Maxwell 76 - 455 (AAU, BK, L); Khao Tao, Hua Hin, Simitinand 1459 (BKF); ibid., 10 Nov 1928, Marcan 2450 (BM, K); ibid., 20 m alt., 9 Nov 1928, Kerr 16164 (AAU, BK, BM, K). Central: Lop Buri, Lam Narai, 50 m alt., 13 Nov 1975, Smitinand 12102 (BKF); ibid., 50 m alt., 13 Nov 1975, Smitinand 12109 (BKF); Phatthana Nikhom, Ban Diluang, km 29-30, 100 m alt., 17 May 2004, Pooma et al. 3989 (BKF); Saraburi, 5 Sept 1954, Bunnag 10 (BK). Peninsular: Chumphon, Bang Son, Pathio, 20 m alt., 10 Jan 1927, Kerr 11351 (BK, BM, E, K, L) .

Diagnostic characters.

Euploca paniculata is erect with unbranched to few-branched stems that are woody at the base. The distinguishing features are linear leaves with greyish tomentose hairs, the spike-like inflorescences arranged in one rank that can elongate up to 20 cm and flowers with pedicels up to 2 mm long. The herbarium specimens from Thailand have mostly been confused with E. strigosa, but these two species can be differentiated by leaf shape and type of induments that are greyish tomentose ( E. paniculata) and strigose ( E. strigosa) on both leaf surfaces.