Dichocarpum yongshanense R. Li, Y. L. Wen & E. D. Liu 2024, sp. nov.
Creators: name: Li, Rong
name: Wen, Yan-Li
name: Zhao, Yong-Li
name: Liu, En-De
name: Li, Wei
Publisher: name: Zenodo
Year: 2024
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Magnoliopsida
Ranunculales
Ranunculaceae
Dichocarpum
Dichocarpum yongshanense

description: Dichocarpum yongshanense R.Li, Y.L.Wen & E.D.Liu, sp. nov. (Fig. 1)
Diagnosis: —It is similar to D. hypoglaucum W.T.Wang & P.K.Hsiao in Hsiao & Wang (1964: 327), but it differs from the latter by plant with only two (vs four) basal leaves with membranous (vs herbaceous) and abaxially non-pruinose (vs pruinose) blade, and by flower with pinkish (vs white) sepals.
Type: — CHINA. Yunnan: Zhaotong City, Yongshan County, Huixi township, Desheng village, Niuguntang, subtropical evergreen broad-leaved forest, under forest in mountains, elev. ca. 2030 m, 28°14′55.8″N, 103°53′46.7″E, 30 April 2022, LED 12409 (holotype KUN!; isotype KUN!).
Perennial herbs, erect, glabrous. Rhizome present, lateral roots dense. Leaves 2, basal, pedately compound, 7–9- foliolate, membranous, green, abaxially non-pruinose; petiole 28–33 cm long; leaf blade 15–20 × 14–18 cm; central leaflet petiolule ca. 3–8 cm long; leaflet blade rhombic-ovate, 9–12 × 4.5–6 cm, base cuneate, apex attenuate, above mid-lower margin with shallow teeth; lateral leaflets 2, petiolule 1.5–4 cm long; leaflet blade obliquely rhombic-ovate, unequal in size, lower leaflets 2.5–6 × 1.5–4 cm, upper leaflet 6.5–11.5 × 3.5–7 cm, margin crenate. Flowering stem ca. 32 cm tall. Inflorescences monochasial, 3–8-flowered; bracts sessile, obovate, 3-lobed, lower bracts 8–12 mm long, upper bracts ca. 1–2 mm long. Flowers 1.2–1.6 cm in diameter. Pedicel 1–2 cm long. Sepals 5, obovate-elliptic, pinkish, 7–10 × 3.5–4.5 mm, apex obtuse. Petal limbs broadly obovate to suborbicular, golden-yellow, ca. 1.3–1.5 mm, apex retuse; claw longer than limb, ca. 2.5 mm long. Stamens numerous, ca. 6.5 mm long; anthers broadly ellipsoid, ca. 0.6 mm long. Pistils 2, connate at base; ovary narrowly obovate, ca. 6 mm long, persistent styles ca. 1.5 mm long. Follicles 2, divaricate, obovoid-lanceolate, ca. 8–10 mm long, beaks ca. 2 mm long. Seeds brown, subglobose, ca. 1 mm in diameter, smooth.
Distribution and habitat: — Dichocarpum yongshanense is currently known only from three sites in the Wumeng mountains in Yongshan County, Yunnan Province, China. It grows in forests at 2000–2200 m elevation.
Conservation status: —The species has been collected only from the type locality and is therefore assumed to be rare. According to guidelines for using the IUCN red list categories and criteria (IUCN Standards and Petitions Committee 2022), it is considered as ‘Endangered’ (EN) using the criteria set out by IUCN as its known area of occupancy is less than 500 km 2 (criterion B2) and the total population size is estimated to be smaller than 2500 mature individuals (criterion C).
Phenology: — Dichocarpum yongshanense was observed with flowers in April to May, and fruits in May to June.
Etymology: —The specific epithet of the new species refers to its type locality.
Vernacular name: —‘ 永ě人ṪAE ’ (Yong Shan Ren Zi Guo) in Chinese.
Additional specimens examined (paratypes): — CHINA. Yunnan: Zhaotong City, Yongshan County, Tuanjie township, Sutian village, Sanjiangkou, subtropical evergreen broad-leaved forest, under forest in mountains, elev. ca. 2100 m, 28°14′53″N, 103°53′41″E, 11 May 2019, Wei Li 1021 (KUN!); Huixi township, Desheng village, Niuguntang, subtropical evergreen broad-leaved forest, under forest in mountains, elev. ca. 2050 m, 28°14′51.1″N, 103°53′42.6″E, 30 April 2020, Wei Li 1882 (KUN!); Tuanjie township, Sutian village, Sanjiangkou, subtropical evergreen broad-leaved forest, under forest in mountains, elev. ca. 2150 m, 28°14′52.6″N, 103°53′45.5″E, 26 May 2021, Wei Li 2334 (KUN!).
description: Published as part of Li, Rong, Wen, Yan-Li, Zhao, Yong-Li, Liu, En-De & Li, Wei, 2024, A new species of Dichocarpum (Ranunculaceae) from northeastern Yunnan, China, pp. 171-175 in Phytotaxa 633 (2) on pages 171-173, DOI: 10.11646/phytotaxa.633.2.8, http://zenodo.org/record/13879134