Lasianthus trichophlebus Hemsl. (1888: 388)

Dang, Van-Son & Naiki, Akiyo, 2023, A revision of the genus Lasianthus Jack (Rubiaceae) from Vietnam, Phytotaxa 581 (1), pp. 1921-1935 : 1921-1935

69. Lasianthus trichophlebus Hemsl. (1888: 388) — Fig. 101 (plate), Fig. 99 (map)

Type: — CHINA. Guangdong, Luo Fu Shan , 7 August 1883, C. Ford 113 (holotype K! [K000763824]) .

Lasianthus barbellatus Ridl. (1917: 187) . Type:— MALAYSIA. Pahang, Pulau Tiuman, Juara Bay , 22 June 1915, Burkill 976 (isotypes K! [K000763901]).

Lasianthus cupreus Pierre ex Pit. (1924: 392) . Type :— VIETNAM. Ba Ria— Vung Tau, Con Dao District, October 1876, Harmand 6173 (lectotypes P! [P02285252, P02285253], designated by Zhu 2001).

Specimens examined: — VIETNAM. Central: Gia Lai Province, Kon Ka Kinh National Park , 905 m elev., August 2019, Oguri E., Tagane S., Sugai K., Suyama Y. & Bui H.Q. V10808 ( HN) ; in the same location, K’Bang District, Son Lang Commune, Kon Chu Rang Nature Reserve , 1100 m elev., 22 April 2021, Van-Son Dang, Ba Vuong Truong & Minh Tam Thao Ngoc Duong, Dang 454 ( VNM) . Southern: Ba Ria—Vung Tau Province, Con Dao National Park , 50 m elev., 22 December 2018, Dang V.S., Dang 298 & Dang 299 ( VNM) ;

Distribution: —Widespread in the tropical and subtropical regions in Asia ( China, India, Indonesia, Malaysia, Philippines, Thailand). In Vietnam, Lasianthus trichophlebus occurs in An Giang, Ba Ria—Vung Tau, and Gia Lai.

Habitat & Ecology: —Growing under shade of evergreen forest or in hill and edge of evergreen montane forest at 50–1000 m elev.

Phenology: —Flowering and fruiting from July to December.

Vernacular name: —Xú hưƠng ten đồng.

Notes: —This species was clarified in the revision by Zhu et al. (2012) and a Vietnamese species, L. cupreus Pierre ex Pit. (1924: 392) was treated as the synonym of L. trichophlebus . It is easily identified in the field in having sparsely strigillose or glabrous on branches, secondary veins 7–9 on each side of midrib, flowers yellowish white, and fruits subglobose, black when ripe, pyrenes 4.

Figures

FIGURE 99. Distribution maps of Lasianthus thuathienhuensis, L. thuyanae, L. trichophlebus and L. verticillatus.

FIGURE 101. Lasianthus trichophlebus Hemsl. (A–E & H–J from Dang 298 and F–G from V10808, VNM and HN): A. Habit, B. Branch with fruits, C. Stipules, D. Abaxial leaf surfaces, E–G. Inflorescence showing lateral view buds and flower, H–I. Young fruits, J. Mature fruits (F–G: photos by Shuichiro Tagane).