Dryopteris jinpingensis Z.Y.Zuo, Jin Mei Lu & D.Z.Li, 2024

Zuo, Zheng-Yu, Lu, Jin-Mei, Li, Cun-Fu & Li, De-Zhu, 2024, Dryopteris jinpingensis, a critically endangered diploid new species of Dryopteridaceae from Yunnan, China, PhytoKeys 239, pp. 195-204 : 195

Dryopteris jinpingensis Z.Y.Zuo, Jin Mei Lu & D.Z.Li sp. nov.

Figs 1 , 2 in Chinese: 金平鳞毛蕨 (jīn píng lín máo jué)

Type.

China. Yunnan: Jinping , 25°17′N, 98°46′E, alt. 1050 m, 20 April 2023, Z.Y. Zuo 5378 (Holotype, mounted in 3 cross-referenced sheets, KUN-1585758! Isotype: KUN-1585759!) .

Diagnosis.

Dryopteris jinpingensis is similar to D. gaoligongensis with stout and creeping rhizome, 3- to 4-pinnate large frond, and largest and longest basal basiscopic pinnule. However, D. jinpingensis differs from it in the elongated lanceolate lamina, sessile or subsessile pinna stalks (less than 1 cm), and overlapping membranous and thin scales adnate to stipe base.

Description.

Plants 70-140 cm tall. Rhizome stout, creeping, up to 20 cm long and 4 cm in diameter, densely clothed with brown, lanceolate, entire scales. Fronds approximate, stipe shorter than lamina, ca. 30-60 cm, brown at base, upper stramineous, densely scaly; scales thin, lanceolate, entire, brown, overlapping and adnate to the stipe base. Rachis and costae hairy when young, glabrous when mature. Lamina papery, not glossy, broadly elongated lanceolate, ca. 40-100 × 20-50 cm, 3- to 4-pinnate, base not narrowed, apex acuminate, abaxial with glandular hairs when young, glabrous when mature. Pinnae 15-30 pairs, opposite, oblique, sessile or subsessile (less than 1cm). Pinnae lanceolate, basal pinnae largest, deltoid-lanceolate, up to 40 × 18 cm, apex caudate-acuminate. Pinnules 25-35 pairs, opposite at base and alternate upward, lanceolate, base broadly cuneate, usually asymmetrical, apex long acuminate; basal basiscopic pinnule largest and longest, ca. 12 × 4 cm, base widest, 2-pinnate; Segments oblong, apices obtuse and spinulose, margin shallowly lobed to several serrate. Veins pinnate, forked, distinct on both surfaces. Sori close to costa on pinnules; indusia orbicular-reniform, entire. Reproductive mode and ploidy level: diploid sexual.

Distribution and habitat.

Presently only known from Jinping County, Yunnan Province, southwestern China, with two documented small populations near each other. It grows on the cliff of the valley in subtropical evergreen broad-leaved forests, at an altitude of 1000-1100 meters.

Etymology.

The specific epithet “jinpingensis” refers to its type locality, Jinping County, in the border between south Yunnan of China and Vietnam.

Conservation status.

Dryopteris jinpingensis should be classified as critically endangered (CR) according to the IUCN guidelines ( IUCN Standards and Petitions Committee 2022), due to its narrow distribution with only two small populations with fewer than 50 plants. In order to conserve and save this rare and endangered species, we have begun to propagate it using the in vitro culture from spores, facilitated by the Germplasm Bank of Wild Species.

Figures

Figure 1. Photos of Dryopteris jinpingensis (Z. Y. Zuo 5378) A habitat B plant C proximal part of the lamina D sori on ultimate pinnules E glandular hairs on the abaxial surface of pinnules F young plant G rhizome H portion of stipe base, showing adnate scale I scales of stipe.

Figure 2. Illustration of Dryopteris jinpingensis Z. Y. Zuo, Jin Mei Lu & D. Z. Li A plant B sori on ultimate pinnules C glandular hairs on the abaxial surface of pinnules D indusia E young plant F scales of stipe (Drawn by Yi-Fan Li, based on Z. Y. Zuo 5378).