Mahonia nanlingensis Y.Tong & Z.D.Wang, 2024

Mahonia nanlingensis Y.Tong & Z.D.Wang , sp. nov. ( Figs. 2–5 View FIGURE 2 View FIGURE 3 View FIGURE 4 View FIGURE 5 )

Type:— CHINA. Guangdong Province, Ruyuan Yao Autonomous County, Daqiao Town, Tianzhushan Village , 24°58’2.80”N, 113°11’2.65”E, 535 m a.s.l., broad-leaved evergreen forest margin, 22 Oct 2023, fr., Y. Tong, Z. D. Wang, Z. C. Fan TY23102201 (holotype: IBSC GoogleMaps ; isotypes: GUCM GoogleMaps ).

Diagnosis:— Mahonia nanlingensis is most similar to M. bodinieri in leaves and fruit. However, M. nanlingensis can be readily distinguished by its cuspidate leaflet apex, truncate stamen apex, narrowly incised petal apex, and emarginate inner sepals. Additionally, M. nanlingensis has a shallowly toothed apex on the lower leaflets, with shorter apical teeth (approximately 0.5 cm) and 7–9 teeth on each side of the leaflet, while M. bodinieri has 4–6 deeper teeth per side, with a longer apical tooth (approximately 1 cm). It is also morphologically similar to M. duclouxiana and M. hancockiana in habit and in having 7–11 leaflets with elongate elliptical leaf blades and shallowly serrated leaf margins. However, it can be distinguished by the stout, unbranched inflorescence, broadly spoon-shaped bract, petals basally glandless, apex narrowly incised, ovules 2 per ovary, stigma broadly discoid, pericarp waxy white pruinose with obvious reticulation and carpopodium twice as long as bract. Mahonia nanlingensis may also be confused with M. cardiophylla and M. bealei , particularly in habit and tender leaves. However, it can be distinguished by leaflets long elliptic, blade abaxially green and not glaucous, margins from the 3rd leaflets 7 or 9 fine-toothed and 5 or 6 pairs of lateral veins from the midrib of each leaflet with apex obviously netted (see Table 1 View TABLE 1 ).

Description:—Shrubs or small trees, 0.5–3 m tall. Bark cork-like, deeply furrowed. Bud scales triangular, ca. 3 × 0.5 cm, green and then becoming reddish brown when flowering. Leaves abaxially yellowish green, not glaucous, adaxially dark green, lucid, ovate-oblong to lanceolate, 50–60 × 20–30 cm, with (6)7–8 pairs of leaflets, lowest pair 0.5–1 cm above base of petiole; venations distinctly reticulate on both surfaces, 5-veined from base with 1 vein usually obscure abaxially, lateral veins 5 or 6 pairs, anastomosing near margin; rachis stout, 2–4 mm in diam.; internodes (2–) 5–9 cm long, the uppermost internode shorter, lowermost internode longest, middle internodes nearly equal. Leaflets subsessile, lowest suborbicular, 3–3.5 × 2–2.5 cm, those above becoming oblong to broadly lanceolate, 12–15 × 4.5–6 cm, base oblique, truncate to cuneate, apex cuspidate, margins of 1st–2nd leaflets with 3 or 5 coarse teeth, 3 rd –8 th leaflets with 7 or 9 smaller teeth, upper leaflets with few (sometimes 5–7) fine teeth 2–3 mm long; terminal leaflet slightly smaller than middle leaflets, 10–15 × 3.5–5 cm, petiolule 2–2.5 cm long. Tender leaves red. Inflorescence of 9 to 15 ascending racemes, 15–20(–25) cm long. Pedicel 2–2.5 mm long; floral bracts narrowly ovate to ovate, 1–1.5 × 0.5–1 mm, apically pointed. Sepals yellow; outer sepals elliptic, purplish red, apex rounded or cordate, ca. 2 × 1.5 mm; median sepals elliptic, ca. 2.5 × 1.5 mm; inner sepals narrowly elliptic, apical emarginate, ca. 3 × 1.5 mm. Petals narrowly elliptic, subequal to median sepals, ca. 3 × 1.5 mm, basally glandless, apex narrowly incised. Stamens 2–2.5 mm long; apex of anthers truncate; anther connective not prolonged. Ovary oblong-ovoid, ca. 1.5 mm long; ovules 2 per locule; stigma broad, flat. Berry initially green and then becoming purplish black when mature, white pruinose, oval or nearly spherical, 4–5 mm in diam., style persistent.

Etymology

The specific epithet “ nanlingensis ” refers to the current known distribution area of the new species, namely the Nanling Mountains. The Chinese name is given as “ 南*十大功劳 ” (Chinese Pronunciation: Nán lǐng shí dà gōng láo).

Habitat, distribution, and phenology

Mahonia nanlingensis is mainly distributed in Guangdong and Guangxi, China ( Fig. 7 View FIGURE 7 ). It grows in broad-leaved evergreen forests and mixed broad-leaved evergreen forests and forest margins at elevations of ca. 50–500 m. Flowering August to October; fruiting October to November.

Conservation status

Mahonia nanlingensis has been collected from over thirty localities and occurs across a vast area covering more than 20,000 km ² in the Nanling Mountains of northern Guangdong provinces and Guangxi. There are 100–150 individuals at the type locality. However, due to medicinal and ornamental uses, as well as a reduction of habitat caused by continuous expansion of land use, the threat risk of this new species seems to be high. Therefore, the species should be regarded as “Vulnerable” (VU) according to A4, B1b and C1 criteria of IUCN Red List Category and Criteria ( IUCN 2022). It is necessary to protect its habitat and collect and preserve its germplasm resources.

Additional Specimens Examined (paratypes). China. Guangdong: Lianshan, Xinlian Village, Shanniutang , 24°33'54.0"N, 112°03'54.8"E, 256 m a.s.l., 1 Sep. 2019 (fr.), Y. Tong 441825190927001LY ( CMMI) GoogleMaps ; Ruyuan, Ruyang Forestry Bureau specimen garden , 500 m a.s.l., 23 Jun. 1973 (fl.), Yue 73 1131 ( IBSC) ; Longxi Town, 6 Nov. 1956 (fr.), Z. Huang 42534 ( IBSC) ; Daqiao Town Ouhui Middle School , 24°58'33"N, 113°11'00"E, 525.2 m a.s.l., 8 Jan. 2016 (fr.), F. G. Wang 440232160108050LY ( CMMI) GoogleMaps ; Daqiao Town, Tianzhushan Village , 24°58'2.80"N, 113°11'2.65"E, 535 m a.s.l., 16 Aug 2022 (fl.), Y. Tong TY22081605 ( GUCM) GoogleMaps ; Renhua, Changjiang Town , 500 m a.s.l., 26 Aug. 1958 (fl. and fr.), L. Deng 7228 ( AU, IBSC, NAS, WUK, PE) ; Sihui, Jianggu Town, Juantou Qu Village , 23°34'18"N, 112°38'17"E, 73.0 m a.s.l., 5 Aug. 2019 (fr.), G. Chen 441284190805519LY ( CMMI) GoogleMaps ; Nanxiong, Lanhe Town, 25°14'27.61"N, 114°05'29.32"E, 445.4 m a.s.l., 13 Nov. 2018 (fr.), Nanxiong Survey 440282181113032LY ( CMMI) GoogleMaps ; Liannan, Near the observation pit in Bandong, Baimang Town, 720 m a.s.l., 16 Aug. 1958 (fl.), P. X. Tan 59032 ( PE, IBSC, NAS) ; Dalong Mountain, Chachang , 24°47'47.1"N, 112°10'54.0"E, 924 m a.s.l., 2 Oct. 2022 (fr.), Y. L. Li LYL22100250 ( GUCM) GoogleMaps ; Lechang, Near Jiufeng Mountain at Zhuangyuan Mountain , 2 Nov. 1932 (fr.), W. T. Tsang 20923 ( PE, NAS, IBSC), N. X. Chen 42147 ( PE) ; Yangshan, Guanpokeng, Libu Town , 2 Aug. 1936 (fr.), L. Deng 244 ( PE, IBSC, NAS) ; Pengyuan, Bachi district, Nankeng Village , 350 m a.s.l., 2 Nov. 1985 (fr.), Z. Y. Yao Ping 8021 ( SN). Guangxi: Lingchuan, Qingshitan Town, At the foot of the mountain near Jiuwu Village , 22 Nov. 2008 (fr.), N. F. Li and L. H. Gao 19182 ( GXMG) ; Haiyang Town, Antai Village, Baidaidi , 25°16'50.8"N, 110°42'59.6"E, 513 m a.s.l., 19 Jun. 2013 (fl. and fr.), Lingchuan Survey 450323130619025LY ( IBK) GoogleMaps ; Ziyuan, Zhongfeng Town, Dayuan Village , 26 Nov. 2008 (fr.), N. F. Li and L. H. Gao 19273 ( GXMG) ; Quanzhou, Caiwan Town, Wufu Village , 25 Oct. 1958 (fr.), Z. C. Chen 52694 ( IBK, KUN) ; Yangshuo, Jinbao Town, Sancha River Estuary , 24°49'19"N, 110°15'22"E, 340 m a.s.l., 6 Nov. 2018 (fr.), Yangshuo Survey 450321181106018LY ( IBK) GoogleMaps ; Lingui, Liutang Town , 18 Jan. 1948 (fr.), Z. N. Deng 13318 ( IBSC) .