Lasianthus viridiramulis Tagane (2015:173)

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

72. Lasianthus viridiramulis Tagane (2015:173) — Fig. 105 (plate), Fig. 104 (map)

Lasianthus brevipes Craib (1933: 20) , nom. illeg.; Saprosma brevipes H. Zhu (2001: 148) ; Paralasianthus brevipes (H. Zhu) H. Zhu (2015: 275) . Type: — THAILAND. Nakhon Si Thammarat, 10 May 1928, A.F.G.Kerr 15641 (( holotype K! [K000777001]).

Specimens examined: — VIETNAM. Central: Khanh Hoa Province, Hon Ba Nature Reserve, 617 m elev., 21 February 2014, Toyama H., Dang V.S., Tagane S., Fuse K., Yahara T., Nagamasu H., Tran H. with Ngoc N.V., Cuong N.Q., Thach N.D., Hieu H.N.P. V 1209 ( FU, VNM, the herbarium of Iriomote Station (Japan)); in the same location, 619 m elev., 16 June 2019, Dang V.S. & Hoang N.T.B. N., Dang 363 ( VNM, the herbarium of Hon Ba Nature Reserve ) .

Distribution: —Southeast Asia region ( Cambodia, Thailand). In Vietnam, Lasianthus viridiramulis occurs in Hon Ba Nature Reserve of Khanh Hoa Province.

Habitat & Ecology: —This species was found under the canopy of the evergreen forest at around 600–800 m elev.

Phenology: —Flowering and fruiting from June to September.

Vernacular name: —Xú hưƠng xanh lục.

Notes: — Lasianthus viridiramulis is a new record for the flora of Vietnam. This name is accepted in a publication based on molecular evidence by Naiki et al. (2015). It is characterized in having elliptic to lanceolate leaves, secondary veins 8–10 on each side of midrib, flowers pedicellate, calyx greenish white and corolla white, and fruits ovoid with 2 pyrenes.

Figures

FIGURE 104. Distribution maps of Lasianthus vietnamensis, L. viridiramulis, L. vuquangensis, L. yaharae and L. yersinii.

FIGURE 105. Lasianthus viridiramulis Tagane (from Dang 363, VNM and the herbarium of Iriomote Station (Japan)): A. Branch with fruits, B. Stipules, C. Abaxial leaf surfaces, D–E. Inflorescence showing lateral view flower buds, F. Flower, G. Young fruits, H–I. Fruits.