Osmanthus fragrans Loureiro (1790: 29)

Diep, Tran Thi Ngoc, Doan, Ha Thi Thanh, Quang, Bui Hong, Averyanov, Leonid V., Lyskov, Dmitry F., Samigullin, Tahir H., Sennikov, Alexander N. & Nuraliev, Maxim S., 2025, An overview of the genus Osmanthus (Oleaceae) in Vietnam, with two new records and lectotypifications, Phytotaxa 684 (1), pp. 33-54 : 36-40

1. Osmanthus fragrans Loureiro (1790: 29) ( Figs. 2 , 3 )

References: — Spach (1839: 268), Clarke (1882: 606), Gagnepain (1933: 1062), Handel-Mazzetti (1936: 1005), Green (1958: 484, 2000: 279, Fig. 13, 2003: 265), Pai (1986: 624), Lu (1992: 107, Pl. 29 Fig. 4–6 ), Yamazaki (1993: 130), Chang et al. (1996: 292, Fig. 249 (4–6)), Ho (2003: 890), Ly (2003: 1168), Xiang & Ji (2004: 48).

LECTOTYPE (designated by Green (1958: 490)):—[ VIETNAM.] Cochinchina , J. Loureiro s.n. ( BM: BM000997627 !).

Image of lectotype available at: https://data.nhm.ac.uk/object/1f70dcc8-24da-467b-b7e5-0d3c9e8924a5

Lists of synonyms are given by Green (1958), Lu (1992), Yamazaki (1993), Chang et al. (1996) and Xiang & Ji (2004). Green (1958) provided an extensive discussion on some of the synonyms.

Nomenclatural notes: — Bui (2016) erroneously indicated the presence of the syntypes of O. fragrans at K and P. The material studied by him is here proved to represent the syntypes of Olea acuminata Wall. ex Don (1837: 49) , a heterotypic synonym of O. fragrans .

Taxonomic notes: —It is remarkable that the specimen Bui, Tran Quang-Osmanthus assigned here to O. fragrans on the basis of morphological and molecular evidence was collected at the same locality as the specimen Bui 100 identified as O. yunnanensis . Although these two specimens are superficially similar, O. fragrans and O. yunnanensis distinctly differ in the gynoecium structure (see a note under the latter species). The gynoecium features were crucial for identification of Bui 100, whereas Bui, Tran Quang-Osmanthus is apparently a male individual to which the gynoecium comparison cannot be applied. Apparently, similar-looking species of Osmanthus co-occur with each other in some habitats, which should be taked into account during floristic assessments. We argue that each individual should be processed (numbered) separately and carefully investigated, in order to avoid mixed gatherings.

Notes on ecology: —In Phia Oac-Phia Den National Park, the population of O. fragrans (represented by the specimen Nuraliev 2302) is of special environmental importance, since it is a dominant tree species in wet mossy forest that covers the Phia Oac summit area. In this area, numerous old thick-boled individuals of the species were observed.

Additional specimens examined:— VIETNAM. Lao Cai Province: Sa Pa District, Hoang Lien National Park , N 22°19'14.5'' E 103°46'15.6'', elev. 2617 m, 31August 2022, H. Q. Bui, D. B. Tran Quang-Osmanthus ( HN: HN000076378 ; MW: MW1046195 , MW1046196 ) ; Cao Bang Province: Nguyen Binh District, Phia Oac-Phia Den National Park, 11 km WSW of Nguyen Binh town, near road to Phia Oac summit, wet mossy forest, N 22°36’48’’ E 105°51’59’’, elev. 1840 m, 11 October 2018, M. S. Nuraliev 2302 ( HN: HN000076377 ; MW: MW0756075 , MW0756076 ) .

Distribution:— Pakistan, India, Nepal, Japan, China, Taiwan, Myanmar, Thailand, Cambodia, Vietnam. Native distribution is somewhat unclear due to extensive cultivation: in partucular, the presence of natural populations in Japan and China is questionable ( Green 2000).

Ecology and habitat: —Moss forests in mountains.

Figures

FIGURE 2. Osmanthus fragrans (apparently a male individual). A. Flowering branch (view from below). B. Leafy branch (view from above). C. Apical portion of shoot. D, E. Leaves, adaxial and abaxial side. F, G. Inflorescences, top and side view. Nuraliev 2302. Photos by M.S. Nuraliev.

FIGURE 3. Osmanthus fragrans (apparently a male individual), floral morphology. A, B. Flowers at early and late stages of anthesis (top view). C, D. Flowers (side view). E. Longitudinally dissected flower. F, G. Calyx and gynoecium (side view). Nuraliev 2302. Photos by M.S. Nuraliev.

FIGURE 4. Osmanthus heterophyllus (apparently a male individual). A. Flowering branches. B. Inflorescences. C, D. Leaves, adaxial and abaxial side. E. Inflorescence bract. F. Longitudinally opened flower. G. Calyx and gynoecium (side view). Averyanov et al. HAL 3478. Photos by L.V. Averyanov (A, B) and Bui Hong Quang (C–G, from dried specimen).

FIGURE 5. Osmanthus heterophyllus (apparently a male individual). A. Flowering branch. B. Inflorescence in leaf axil. C. Flower (side view). D, E. Flowers (top view). F. Corolla lobe. G. stamens. Drawn from Averyanov et al. HAL 3478 (HN) by Le Kim Chi.

FIGURE 6. Distribution of Osmanthus heterophyllus and O. yunnanensis in Vietnam.