Diospyros adinandrifolia Y. M. Shui, Z. X. Zhang & C. Y. Zou, sp. nov.
Creators: name: Liu, Qun
name: Zou, Chun-Yu
name: Yang, Chong
name: Chen, Wen-Hong
name: Lyu, Ling
name: Zhang, Gui-Liang
name: Shui, Yu-Min
name: Zhang, Zhi-Xiang
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Ericales
Ebenaceae
Diospyros
Diospyros adinandrifolia

description: Diospyros adinandrifolia Y.M. Shui, Z.X. Zhang & C.Y. Zou sp. nov. (Figs. 1–5)
Type: — CHINA. Yunnan: Hekou County, Nanxi Town, Longbao Village, elevation 750 m, in the tropical rainy forest along the limestone valley, 10 April 2023, female flowers, C. Y. Zou, J. Q. Huang & Z. C. Fan ZCY4316 (holotype: IBK!; isotype: KUN!).
Diagnosis: —The new species resembles Diospyros undulata Wall. ex G. Don (1838: 40) and D. dussaudii Lecomte (1928: 113). It is similar to D. undulata in its elliptic leaves, clustered flowers, and synsepalous calyces, but differs in its abaxial leaf base without glands (vs. with a pair of glands), calyx lobes being absent or less than 1/10 as long as the whole calyx (vs. approximately 1/3–1/2 as long as the calyx), fruiting calyx lobes being not reflexed and almost not wrapping the base of fruit (vs. reflexed and wrapping up to 1/2 of fruit), and its fruit being 4–5 cm (vs. 1.5–2.6 cm) in diameter. It is also similar to D. dussaudii Lecomte in having similar buds and flowers, but differs in its leaves being white pubescent when young and glabrescent (vs. densely ochre brown villous), racemose (vs. fasciculate) male inflorescences, and succulent (vs. xyloid) fruit (Table 1).
Evergreen plants, dioecious. Tree to 20 m tall, trunk to 71 cm in diameter at breast height (DBH); bark grey, densely lenticellate. Young branchlets green. Twigs with appressed whitish pubescence when young, becoming glabrous with age. Buds covered by bifarious scales. Leaves leather, lanceolate or elliptic-lanceolate, 6.0– 18.5 cm long, 2.0–6.0 cm wide, apex acute or acuminate, base cuneate or broadly cuneate, mid-rib adaxially impressed, mid-rib abaxially prominent, white pubescent when young; lateral veins pinnate, 7–10 pairs, slender; veinlets obviously reticulate; Petiole 0.6–1.3 cm, white pubescent; buds brown pubescent. Flower buds ovoid, with bifarious scales at base, scales 3–6, broadly ovate, brown strigose, deciduous after flowering. Male inflorescences racemose, 2–4 cm long, each bearing 3–6 flowers. Male flowers 4(–3)-merous, calyx cylindrical, with 4(–3) short triangular lobes, 5–7 mm, densely covered with long white hairs; corolla pale yellow, urceolate, pubescent outside, glabrous inside, lobes ovateorbicular, reflexed; stamens 16, arranged in 2 series, attached at the base of corolla tube; anthers triangular, 4.0–6.0 × 1.5–3.0 mm, apex apiculate, white pubescent; rudimentary ovary densely pubescent. Female inflorescences consisting of a solitary flower on a ca. 0.2 cm long stalk. Female flowers 4(–3)-merous, calyx tubular, margin emarginate; corolla pale yellow, urceolate, lobes ovoid, reflexed, densely pubescent outside, glabrous inside; Staminodes 8, attached at the base of corolla tube, filaments flattened, anthers triangular; ovary globose, densely white pubescent, 8-locular; stigmas 4. Fruit succulent, globose or depressed-globose, angular-sulcate, 3.5–5.8 cm in diam., covered with silvery-grey hairs; persistent calyx leathery, 1.5–2.0 cm in diameter, outside densely silvery-white hairs, inside nearly glabrous; fruiting stalk stout, ca. 1.0 cm long, densely silvery-white hairs; light green when immature, turning yellow and orange when ripe, with 2–8 seeds; Seeds dark brown, triangular-oblong, compressed, 2.5–3.2 cm long, 1.5–2.0 cm wide.
Phenology & ecology: —Flowering April, fruiting from May to August.
Etymology: —The specific epithet is due to the leaf shape and texture resembling those of the genus Adinandra Jack (1822: 49) in Theaceae. The Chinese name for this species is: 杨桐柿.
Habitat & distribution: —At present, this species has been discovered in the permanent monitoring plot of tropical rainforest in the Gulinqing Natural Reserve of Maguan County and Hekou County, southeast Yunnan, where the topography is a typical karst depression, and the habitat is relatively fragile and fragmented due to nearby farming. It is scattered in the tropical rainy forests at elevations of 530–800 m, mainly composed of species such as Caryodaphnopsis tonkinensi s (Lecomte 1913: 106) Airy Shaw (1940: 74), Pometia pinnata Forster & Forster (1776: 110), Phrynium rheedei Suresh & Nicolson (1986: 355).
Additional specimens examined (paratypes): — CHINA. Yunnan: Hekou County, Nanxi Town, elevation 800 m, 11 April 2023, male flowers, C.Y. Zou, J.Q. Huang & Z.C. Fan ZCY4320 (IBK, KUN, IBSC); Maguan County, Gulinqing Community, Bojia Village, the 25-ha permanent monitoring plot of the tropical rain forest, elevation 530– 610 m, 22°42’58”N, 103°53’42”E, 4 September 2023, Yu-Min Shui et al. GLQ0204-106 (KUN).
Conservation status: —At present, this species is known in two localities in Yunnan with a total of less than 69 mature individuals. Some individuals discovered occur within the range of reserves, where the habitats are in good condition. A small number of individuals are disturbed by agricultural activities. The localities are close to Vietnam, possibly expanding to North Vietnam. According to IUCN Standards and Petitions Subcommittee (2022), this new species should be regarded as Endangered (EN).
description: Published as part of Liu, Qun, Zou, Chun-Yu, Yang, Chong, Chen, Wen-Hong, Lyu, Ling, Zhang, Gui-Liang, Shui, Yu-Min & Zhang, Zhi-Xiang, 2024, Diospyros adinandrifolia, a new species of Ebenaceae from Yunnan, China, pp. 121-129 in Phytotaxa 649 (1) on pages 122-127, DOI: 10.11646/phytotaxa.649.1.8, http://zenodo.org/record/13215940