Toxicodendron oligophyllum (Anacardiaceae), a new species from Fujian, China: evidence from morphological and molecular analyses Author Tang, Shu-Ling 0000-0001-6834-8677 Zhangzhou Institute of Technology, Zhangzhou 363000, China. & fjzzztsl @ 126. com; https: // orcid. org / 0000 - 0001 - 6834 - 8677 Author Chen, Xin-Yan 0000-0002-8632-2216 Sanming City Garden Center, Sanming 365000, China. & 303983900 @ qq. com; https: // orcid. org / 0000 - 0002 - 8632 - 2216 303983900@qq.com Author Ma, Liang 0000-0002-7366-7290 College of Landscape Architecture, Fujian Agriculture and Forestry University, Fuzhou 350002, China. & fjmaliang @ 126. com; https: // orcid. org / 0000 - 0002 - 7366 - 7290 Author Ni, Bi-Yong 0000-0002-7339-0770 Urban and Rural Construction and Transportation Service Center of Pingtan Comprehensive Experimental Area, Pingtan 350400, China. & 287974186 @ qq. com; https: // orcid. org / 0000 - 0002 - 7339 - 0770 287974186@qq.com Author Pan, Biao-Zhi 0000-0002-4592-3277 Fujian Forest Inventory and Planning Institute, Fuzhou 350003, China. & lkycsj @ 126. com; https: // orcid. org / 0000 - 0002 - 4592 - 3277 Author Chen, Shi-Pin 0000-0002-8090-6616 College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China. & fjcsp @ 126. com; https: // orcid. org / 0000 - 0002 - 8090 - 6616 text Phytotaxa 2022 2022-03-11 539 1 55 61 http://dx.doi.org/10.11646/phytotaxa.539.1.6 journal article 20231 10.11646/phytotaxa.539.1.6 b4c37cf6-611b-4f88-a7d0-7bf0e8b37a78 1179-3163 6345945 Toxicodendron oligophyllum S. L. Tang, Liang Ma & S. P. Chen , sp. nov. ( Fig. 2 & Fig. 3 : A–G). This new species is similar to T. acuminatum (DC.) C. Y. Wu & T. L. Ming , T. succedaneum (L.) Kuntze and T. sylvestre (Sieb. & Zucc.) Kuntze , but can be distinguished by its glabrous branchlet, leaf and inflorescence, 3–5 leaflets, and the length of inflorescence equal to the leaf. Type: — CHINA , Fujian : Yongtai County , terrestrial in evergreen broad-leaved forests on cliffs formed by weathering of volcanic rocks, alt. 733 m , May 2019 , MA 20190519 ( holotype , FJFC !; isotype, CSH !) . FIGURE 3. Toxicodendron oligophyllum and related species. T. oligophyllum ( A. Habitat; B. Flowering branches; C. Leaf, abaxial view; D–E. Flowers; F. Infructescence; G. seed); T. sylvestre ( H. Branchlets, I. Leaves) ; T. succedaneum ( J. Branchlets, K. Leaves) . Deciduous trees or small trees to 12 m tall; phloem with white latex and turning black upon air exposure; branchlets and buds purple-brown, glabrous. Petiole 3–5 cm , petiole and rachis slender, glabrous; leaf blade imparipinnately compound, 10–15 cm long; leaflets 3–5, opposite; leaflet petiolule indistinct or 2–7 mm long; leaflet blade ovate to ovate-elliptic, 5–7 × 2–4 cm , thinly leathery, glabrous on both surfaces, adaxially dark-green, abaxially glaucous, margin entire, base ± oblique, broadly cuneate or rounded, apex acuminate to caudate-acuminate; lateral veins 15– 20 pairs, slightly prominent on both surfaces. Inflorescence paniculate, 10–15 cm long, many branched, glabrous. Pedicel 4–5 mm long; flowers yellowish green, ca. 2 mm in diam. Calyx glabrous, lobes broadly ovate, ca. 1 × 0.8 mm , obtuse apically. Petals oblong, ca. 2 × 1.5 mm , obtuse apically, with ± conspicuous featherlike venation pattern, revolute at anthesis. Stamens exserted; filaments linear, ca. 2 mm long; anthers ovoid-oblong, ca. 1 mm long. Disk 5-lobed. Ovary globose, ca. 8 mm in diam., glabrous. Drupe large, asymmetrical, ca. 8 mm in diam., compressed, apex eccentric; epicarp thin, glabrous, lucid, separating; mesocarp thick, waxy, with brown longitudinal resin ducts; endocarp compressed, ca. 3 × 5 mm . Phenology: The species blooms from May to June and fruits from June to October. Etymology: The species epithet refers to its characteristic of having the least number of leaflets in this genus. Chinese name: Ṫ叶¨ (shao ye qi). Distribution and habitat: It mainly grows on cliffs formed by the weathering of volcanic rocks at altitudes of 300– 900 m . It is so far only known from the type locality, i.e. Yongtai County, including Chibi Village, Tianmen Mountain Ecological Scenic Spot and Ximen Village, Fujian Province of China . Conservation State: At present, the new species is only found from its type locality with five populations. Each population of T. oligophyllum is comprised of approximately 200 mature individuals. We believe further observation is needed to find out other locality of the species and therefore, yet we suggest the species to be assessed as Data Deficient (DD; IUCN, 2019 ).