Lasianthus foxworthyanus Craib (1901: 17)

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

25. Lasianthus foxworthyanus Craib (1901: 17) — Fig. 46 (plate), Fig. 47 (map)

Type. THAILAND. Narathiwat, Bacho , 11 June 1930, M.S.Kiah 24312 (isotypes K! SING! [K000777027, SING0059257 ].

Specimens examined: — VIETNAM. Central: Kon Tum Province, Ngoc Linh Nature Reserve , 1070 m elev., 15˚10’05.07”N, 107˚45’23.06’’E, 12 February 2017, Tagane S., Nagamasu H., Nguyen V.N., Hoang T.B., Hoang T.S., Yang C.J., Kawakubo A. V 6415 ( DLU, FU, VNM, the herbarium of Iriomote Station ( Japan)) .

Distribution. Southeast Asia region ( Malaysia, Thailand). In Vietnam, this species occurs in Kon Tum.

Habitat & Ecology. In shaded places of the moist evergreen forests at 300–1200 m elev.

Phenology. Flowering and fruiting from June to November.

Vernacular name. Xú hưƠng foxworthy.

Notes. Lasianthus foxworthyanus is a new record for the flora of Vietnam. It is easily recognizable in the field from other Lasianthus in having densely appressed-pubescent branches; leaves oblong-lanceolate or oblong-elliptic, 9–16 × 3–5 cm, apex acuminate, base cuneate, secondary veins 6–9 on each side of midrib; petioles 5–7 mm long, appressed-pubescent; stipules 4–5 mm long, pubescent; fruit globose with 4 pyrenes.

Figures

FIGURE 46. Lasianthus foxworthyanus Craib (from V6415, FU, VNM and the herbarium of Iriomote Station (Japan)): A. Branch with flower buds, B. Close-up of young branch and leaves, C. Stipules, D. Abaxial leaf surfaces, E. Flower buds, F–H. Young fruits (A, F, H: photos by Shuichiro Tagane).

FIGURE 47. Distribution maps of Lasianthus foxworthyanus, L. giganteus, L. globularis and L. hatinhensis.