Lasianthus obscurus (Blume ex DC) Miquel (1857:317)

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 : 23

40. Lasianthus obscurus (Blume ex DC) Miquel (1857:317) . ≡ Mephitidia obscura Blume ex Augustin Candolle

(1830:453). Type: ― INDONESIA. Java, C. L. Blume s.n. (holotype L0057529 image!). ( Figure 3T )

= Lasianthus kurzii Hooker (1880: 183) var. sylvicola Lo (1993:3) . Type: ― CHINA. Hainan, Expedit 530 (holotype SCBI n.v.).

= Lasianthus kurzii var. fulvus C.Y. Wu & H Zhu in Zhu (1994:60). Type: ― CHINA. Yunnan, Xishuangbanna, Yunnan Expedition 59- 13346 (holotype KUN n.v.).

T hailand: —NORTHERN. Chiang Mai: Doi Inthanon National Park, 15 September 1995, K. Larsen et al. 46436 (AAU, BKF, PSU), 20 October 1999, C. Phengklai 7637 (BKF), 22 July 1988, C. Phengklai 6782 (BKF), Doi Suthep Pui, 13 June 1957, K. Bunchuai 600 (BKF). Nan: 20 December 1971, C. F. van Beusekom et al. 4452 (BKF, K). NORTH-EASTERN. Khon Kaen: Phu Khieo Wildlife Sanctuary, 8 November 1984, G. Murata et al. 41829 (BKF). EASTERN. Nakhon Ratchasima: Khao Yai National Park, 18 July 1973, G. Murata et al. T16252 (BKF), 19 July 1973, G. Murata, N. Fukuoka & C. Phengklai T16350 (BKF), 22 October 1969, C. F. van Beusekom & C. Charoenpol 1822 (BKF), Wang Nam Khieo district, Sakaerat, 28 October 1969, C. F. van Beusekom & C. Charoenpol 1870 (BKF). Nakhon Nayok: Khao Yai National Park, 23 July 2000, S. Chongko 101 (BKF), 10 October 1999, S. Chongko 12 (BKF). SOUTH-EASTERN. Prachin Buri: Khao Yai National Park, 12 July 1966, K. Larsen, T. Smitinand & E. Warncke 340 (AAU, BKF). Trat: Koh Chang, 2 August 1973, G. Murata, N. Fukuoka & C. Phengklai T17419 (BKF).

Distribution: — China (Yunnan, Hainan), Cambodia (Bokor), Vietnam, Indonesia (Java, Sulawesi), Thailand (Northern, North-Eastern, Eastern, South-Eastern).

Ecology: —Evergreen forest, hill evergreen forest, moist evergreen, dry evergreen forests in shaded places at an elevation of 300‒1000 m. Flowering in August‒October and fruiting in November‒January.

Notes: ― Lasianthus obscurus is closely related to L.chrysoneurus but differs by being densely spreading tomentose on branches, abaxial leaf surface, stipules, bracts, and calyx, while L. chrysoneurus has a appressed pubescence on those organs. The two species are separated only by their different indumentum. In addition, in the field we found a conspicuous indumentum on white fresh fruits of L. obscurus whereas L. chrysoneurus has subglabrous or pubescent young and mature fruits.

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.