Calanthe wuxiensis H.P. Deng & F.Q. Yu, 2017

Calanthe wuxiensis H.P. Deng & F.Q. Yu View in CoL , sp. nov. ( Figs. 1–2 View FIGURE 1 View FIGURE 2 )

Type:— CHINA. Chongqing: Wuxi, Yintiaoling National Nature Reserve, forest margins, Yintiaoling , under bamboo forests, 31°31 ′ N, 109°43 ′ E, ca. 2145 m a.s.l., 29 May 2016, H.P. Deng & F.Q. Yu 0529 (holotype SWCTU GoogleMaps , isotype PE GoogleMaps ).

Diagnosis: Calanthe wuxiensis is closely related to C. ecarinata and C. tricarinata , but differs from them in having white lip adnate to the base of column wings and with which forming a tube, rectangular lateral lobes, disk with three dark yellow short-crests at reflexed part.

Description: Terrestrial, 37–40 cm tall. Rhizome inconspicuous. Pseudobulbs small, ca. 1 cm in diam, with 3 sheaths. Leaves 3 to 4, basal, not well developed at anthesis, blade papery, elliptical, 22.2–24.0 cm long, 5–8 cm wide, 3–5-veined, abaxially glabrous, margin undulate, apex acute or acuminate; petiole-like base sheathing, forming a stout pseudostem 4–8 cm long and 1.0– 2.5 cm in diam; sheaths large, apex acuminate, lowest one ca. 2 cm, upper sheaths longer. Scape arising from leaf axil, erect, to 30 cm, to 0.8 cm in diam, stout, puberulent, with several to many ovate-lanceolate sterile bracts; rachis ca. 20–25 cm, usually ca. 8-flowered; floral bracts persistent, ovate-lanceolate, 5–8 mm, membranous, glabrous, apex acute. Flowers pale yellow, lip white; pedicel and ovary 10–20 mm long, puberulent. Dorsal sepal elliptic, 15.2–18.4 × 7.0– 8.4 mm, abaxially glabrous, 3–5-veined, apex acuminate; lateral sepals oblong-lanceolate, 15.2–18.4 × 5.0– 6.4 mm, abaxially glabrous, 3–5-veined, apex acuminate and oblique. Petals obovate-elliptic, 10.0–14.4 × 5.0– 7.4 mm, 3 or 4-veined, apex acute. Lip adnate to base of column wings and forming a tube, white, spurless, 3-lobed near centre; lateral lobes rectangular, longish, wing-like, apex gradually expand, 7–8 × 3–4 mm; mid-lobe backward reflexed from middle part, papilionaceous, 9–10 × 7–8 mm, margin slightly lobed; disk with three dark yellow short-crests at reflexed part; lateral crests 1–2 mm long, 0.2–0.5 mm in height, middle crest 3–4 mm long, 1–1.5 mm in height. Column ca. 7 mm long; rostellum pointed triangular; pollinia waxy, in 2 groups of 8; anther cap semicircular, beaked; flowering in May.

Distribution and habitat: —Currently, Calanthe wuxiense is known only from its type locality with Indocalamus tessellatus (Munro) plants, i.e. the Yintiaoling National Nature Reserve in Wuxi, Chongqing, China ( Fig. 3 View FIGURE 3 ). It occurs at margins of shrub of bamboo forests at ca. 2145 m in elevation.

Phenology: — Calanthe wuxiensis flowers in May, and set fruits from June to August. Seeds maybe disperse until March of the next year.

Etymology: —The specific epithet refers to Wuxi, Chongqing, China, the type locality of the new species.

Discussion. Calanthe wuxiensis is closely related to C. ecarinata and C. tricarinata by possessing small pseudobulbs small with 3 sheaths, 3-4 leaves, pale yellow flowers; spurless lip. Calanthe wuxiensis is a distinctive species, distinguished from latter two by having white lip adnate to base of column wings, rectangular lateral lobes, mid-lobe deflexed from middle part, disk with three dark yellow short-crests ( Table 1 View TABLE 1 ).