Lasianthus attenuatus Jack (1823:126)

Napiroon, Tiwtawat, Chayamarit, Kongkanda, Dawson, Sally, Till, Walter & Balslev, Henrik, 2020, A synopsis of Lasianthus (Lasiantheae, Rubiaceae) in Thailand and two additional new species, Phytotaxa 439 (1), pp. 1-38 : 9-10

3. Lasianthus attenuatus Jack (1823:126) .≡ Mephitidia attenuata (Jack) Candolle (1830:452) . Type: ― INDONESIA.

Sumatra, Bencoolen , W. Jack s.n. (holotype not seen; isotype L0000674 image!). ( Figure 3B & 3C ) .

= Lasianthus densifolius Miquel (1857:321) . Type (lectotype designated by Zhu 2012):― INDONESIA. Java, Ungaran. Junghuhn s.n. (lectotype L0000679 image!).

= Lasianthus densifolius Miq. var. latifolia King & Gamble (1904:122) . Type (lectotype designated by Wong 1989):― MALAYSIA. Johore, 14 October 1900, H. N. Ridley 10948 (lectotype SING0059263 image!).

= Lasianthus setosus (Craib) (1933:26) . Type:― THAILAND. Ranong, Kao Talu, A.F.G. Kerr 11827 (holotype K000777040!)

Thailand: ―NORTHERN. Chiang Mai: Doi Inthanon National Park, 22 February 1979, T. Bjornland & T. Schumacher 722 ( BKF). Nan: Doi Phu Kha National Park, 17 November 1993, K. Larsen et al. 44473 (AAU, BKF, PSU), Doi Khun Sathan National Park, 17 January 2002, P. Srisanga 2400 ( QBG). Phitsanulok: Tung Salaeng Luang Wildlife Sanctuary, 9 February 1964, B. Hansen, G. Seidenfaden & T. Smitinand 11088 (BKF, K), July–August 1966, K. Larsen, T. Smitinand & E. Warncke 808 (BKF, K), 3 October 1967, M. Tagawa T11790 ( BKF). EASTERN: Nakhon Ratchasima: Khao Yai National Park, 10 December 1962, C. Phengklai 433 ( BKF), 14 December 1962, C. Phengklai 497 (BKF, K). PENINSULAR. Krabi: Khao Phanom Bencha National Park, 6 January 2006, S. Gardner & P. Sidisunthorn ST2179 (BKF, K), 9 October 2008, P. Phonsena 6286 ( BKF). Nakhon Si Thammarat: Khao Luang National Park, 23 October 1957, Bunnak 734 ( BKF), 16 May 1968, C. F. Van Beusekom & C. Phengklai 798 (K). Trang: Khao Chong, 31 October 1984, J. F. Maxwell 84-387 (BKF, PSU).

Distribution: ― Nepal, Bhutan, NE India, China, S Japan, Vietnam, Laos, Cambodia, Myanmar, Malaysia (Peninsular and Borneo), Brunei, Philippines, Indonesia (Sumatra, Java, Kalimantan, Sulawesi, Lesser Sunda Islands), Papua New Guinea, Thailand (Northern, Eastern, Peninsular).

Ecology: ―Evergreen forest, in shaded places up to 1000 m elevation. Notes: ― Lasianthus attenuatus was described in 1823, and most of the type material (Jack’s collection) was destroyed by a fire in 1824 ( Merrill 1952, Stafleu & Cowan 1979). The identity of this species was clarified by Zhu et al. (2012) who reported evidence in the form of a line drawing which had been annotated by Merrill (1952). In Thailand, specimens belonging to this species were previously identified as Lasianthus wallichii subsp. plagiophyllus Hance ( Zhu 2001). The morphological variation and continuous geographical distribution of L. attenuatus and L. wallichii Wight (1846:503) in tropical Asia made their distinction difficult even if they had been recocgnized as distinct ( Zhu et al. 2012). We agree that the material represents a single species and therefore cite L. wallichii subsp. plagiophyllus (Hance) Wu Zheng Yi & Zhu as a synonym of L. attenuatus .

Herbarium specimens of L. attenuatus were also sometimes identified as L. cyanocarpus . Now, we know that the best character for their identification is the bract’s shape ( Merrill 1952). Lasianthus attenuatus has linear to lanceolate bracts but L. cyanocarpus has cordate, ovate to broadly lanceolate bracts that are leaf-like as seen in all Thai specimens.

Figures

FIGURE 3A‒O. Lasianthus werefound in Thai naturalforests:A) L. appressus;B) &C) L.attenuatus;D) L.chinensis;E) L.chrysoneurus; F) L. constrictus; G) L. cyanocarpus; H) L. ellipsoideus; I) L. ellipticus; J) L. fordii; K) L. foxworthyanus; L) & M) L. hirsutus; N) L. hispidulus and O) L. inodorus.