Rohdea maoershanensis Jian L.Li & R.H.Jiang, 2024

Rohdea maoershanensis Jian L.Li & R.H.Jiang , sp. nov. ( Fig. 1 View FIGURE 1 )

Type:— CHINA. Guangxi: Guilin City, Xing’an County, Mao’er Mountain National Nature Reserve, alt. 1600 m, 24 April 2024, fullblossom stage, R. H. Jiang et al. 20240424001 (Holotype, GXFI!).

Diagnosis:— R. maoershanensis resembles R. chinensis , but differs based on leaves 9–13, linear (vs 4–8, lanceolate or linear); spike ca. 22 cm long, peduncle base with 2 bracts (vs 2.5–9 cm long, peduncle base lack of bract); bracts triangular lanceolate, shorter than flowers (vs ovate-lanceolate to lanceolate, sometimes longer than flowers); annular appendage formed by expanding the base of the filaments (vs annular appendage abcent); ovary oblate spherical, diameter 4 mm (vs subglobose, diameter 2.5 mm).

Description:— A perennial herb. Rhizome cylindrical, 1–2 cm in diameter. Leaves 9–13 on short stems, papery, linear, 25–45 cm long, 1.2–2 cm wide, apex acuminate, margin whole, flat; leaves sessile, base extended, cauline. Spikes with dense flowers, 1–1.2 cm in diameter, with several sterile bracts at apex and 2 bracts at base; peduncle drawn from leaf clusters, lateral, erect, ca. 22 cm long, base sheathed; peduncle about 8 cm long and 5–7 mm wide. Bracts minimal, triangular-lanceolate, ca. 3 mm × 1.5 mm, apex long pointed, translucent fleshy, green. Perianth ca. 1.5 cm in diameter, filament base enlarged and connected into an annular wavy appendage with rough surface and rodent-like edge; perianth lobes 6, spreading, broadly triangular, ca. 5 mm × 4 mm, fleshy, green when fresh, yellow-green after dry, margin thinner, whole margin; stamens inside annular appendage, filaments very short, base enlarged, conjoined to base of adjacent filaments, anthers ovate, ca. 1 mm long; ovary 3-locular, 2 ovule per chamber, stigma very short, ca. 1 mm long, apex 3-lobed. The young fruit flattened spherical shape, about 4 mm in diameter.

Distribution and ecology:—The distribution of Rohdea maoershanensis is currently limited to a single locality on Mao’er Mountain in Guilin City, Northeast Guangxi.This rare species thrives at the periphery of roadside Rhododendron forests, situated at an elevation of approximately 1600 m. The habitat is characterized by a thick layer of fallen leaves covering the roots, which suggests a preference for moist and well-drained soil conditions that are also abundant in natural light.

Etymology:—Specific epithet is derived from its type locality, the Mao’er Mountain National Nature Reserve, Xing’an County, Guilin City, Guangxi, China.

Phenology:—The species flowers from April to May, with fruiting anticipated to occur from May to July.

Vernacular name:—The Chinese vernacular name for the species is " Dz儿Ɯ开口ẘ " (māo ér shān kāi kǒu jiàn), reflecting its local nomenclature.

Conservation status:—The new species Rohdea maoershanensis has been found only one distribution site in the type locality, and our investigations have revealed the presence of approximately 30 mature individuals. The species' habitat appears to be minimally impacted by human activities.According to the IUCN Red List Categories and Criteria (Version 3.1) [ C 2(a)(ii)], it is temporarily assessed as Endangered (EN).

Similar species:— R. maoershanensis resembles R. chinensis ( Baker 1889: t.1867) N. Tanaka (2003: 331), R. jinshanensis (Z. L. Yang & X. G. Luo 1984: 389) N. Tanaka (2003: 332) , and R. chlorantha , but differs based on bracts about 3 mm long, much shorter than flowers; spike densely many flowers, with several sterile bracts at apex and 2 bracts at base; the filament base expands and joins to form a ring-like appendage, whose inner forms a membranous ring; ovary flattened spherical shape, ca. 4 mm in diameter. A comparison of characteristics of the new species and its relatives is given in detail in Table 1 and Fig. 2.