Thismia jinzun C.Y. Lu, W.H. Qin & Han Xu, 2024

Lu, Chunyang, Yang, Haijun, Qin, Wenhao & Xu, Han, 2024, Thismia jinzun (Thismiaceae), a new species of Thismia Genus from Hainan Island, China, Phytotaxa 664 (4), pp. 273-280 : 274

Thismia jinzun C.Y. Lu, W.H. Qin & Han Xu , sp. nov. ( Figs. 1–3 ). AEṘAEŀẅ

Diagnosis:— Thismia jinzun is similar to T. javanica and T. tentaculata . However it can be distinguished by the following characters: T. jinzun has 10–12 mm long, gold-yellow tepal appendages (vs 20–30 mm long, orange-white in T. javanica , three ca. 17 mm long, orange-red in T. tentaculata ), a gold-yellow floral tube (vs pale orange or pale yellow in T. javanica and white in T. tentaculata ), a gold-yellow annulus (vs orange in T. javanica and bright yellow in T. tentaculata ), and the apical margin of the connective is trilobed, with a hair present at each lobe (vs bilobed or bidentate in T. tentaculata ).

Type:— CHINA. Hainan: Ledong County, Jianfengling national Nature Reserve , 761 m, 18°44′35.99″N, 108°52′09.68″E, 1 October 2023, LuCY2023001 (holotype CANT; isotype IBSC) .

Description. Achlorophyllous herb. Rhizome creeping horizontally, vermiform. Stem simple, erect, 5–7 cm. Leaves white, membranous, appressed to stem, narrowly triangular with acute apex, scale-like, 3–4 mm long. Inflorescence racemose, 2–7 flowers. Flower actinomorphic. Pedicel 3.3–3.5 mm. Bract 1, 8–8.3 mm long. Floral tube urceolate, gold-yellow, translucent, 8.5–9 mm × 5 mm, narrowed towards the ovary; outer surface smooth, with 12 vertical ridges; inner surface reticulated by transverse raised bars and has many spots formed by the accumulation of needle crystals. Tepals 6, arranged in two whorls; Outers 3, broadly triangular, gold-yellow, ca. 2 mm long, 2.3–2.6 mm wide at the base. Inners 3, broadly triangular, gold-yellow 1.3–1.5 mm long, 2.2–2.6 mm wide at base, terminated by filiform appendages 10–12 mm long. Annulus prominent, gold yellow, ca. 0.5 mm high, 1-1.2 mm thick. Stamens 6, pendent below annulus, filaments free, connectives fused into a tube. Filament gold yellow, glabrous, ca. 1 mm long. Connective fleshy, ca. 2.5 mm long, 1 mm wide; apex with 3 teeth, each tooth bearing a distinct stiff hair, ca. 1 mm long; lateral appendage skirt-like, born on the upper part of connective facing the inner surface of floral tube, margin ciliolate. Interstaminal glands small, oblong, ca. 0.4 mm long. Anther 2, oblong, born on the base of connective with the same side as the lateral appendage, 0.6–0.65 mm long. Ovary inferior, obconic, yellowish-white, unilocular, 2.3– 2.5 mm wide; parietal placentas 3; style short, ca. 1 mm; stigma 3-lobed, triangular, ca. 1 mm long, shortly acuminate at apex, its margin slightly revolute with short protrusions. Fruit cup-shaped.

Phenology: —Fl. September-October.

Distribution and habitat: — Thismia jinzun is the second species of Thismia found in Jianfengling national Nature Reserve, Hainan province, China. About 10 individuals are found in the understorey layer of the rainforest at the altitude of 761 m. The habitat is shaded and humid. The dominant tree species are composed of Maclurodendron oligophlebium , Ormosia balansae, Livistona saribus, Gironniera subaequalis and Cinnamomum burmanni .

Etymology: —The specific epithet of this species is inspired by the poem “Invitation to Drink” written by the famous Chinese poet Li Bai in the Tang Dynasty. In the poem, one of the lines is “ Please enjoy your joy when life goes well; Do not let your Jinzun empty when inviting the moon to cheer.” Here, Jinzun means a fine golden cup. When first saw the new species living in the core area of the tropical mountain rainforests and in flowering with golden yellow cup-shaped corolla in Chinese traditional Mid-Autumn Festival, we were completely immersed in Li Bai’s poetic atmosphere. Taking into account both the form and the epithet, Jinzun, is a very appropriate name for the new species.

Conservation status: —Only one population of this new species, with about ten individuals, has been found so far. They are ephemeral and are highly vulnerable to habitat disturbance. Up to date, they have not been found in other areas with similar habitats in the nature reserve, despite extensive investigation. Hence, it is recommended that the conservation status of this species should be assigned as Critically Endangered (CR) according to the IUCN Red List criteria ( IUCN 2019), and the appropriate protection strategies are needed for the new species.

Figures

FIGURE 1. Morphology and habitat pictures of Thismia jinzun sp. nov. A. Open flower; B. and C. Developing flower; D. Entire plant; E. Habitat.

FIGURE 2. Line drawing of Thismia jinzun sp. nov. A. Flower bud; B. Ovary and style with stigma; C. Entire blooming flower; D. Top view of flower; E–F. Entire plant with roots; G. Outer view of stamen includes anthers; H. Inner view of stamen.

FIGURE 3. Thismia jinzun sp. nov. A. Flowering plants collected from the type locality; B. Rhizome; C. Tepals and annulus; D. Inner side surface of floral tube, showing the transverse bars and the spots; E. Needle crystals on the inner side surface of floral tube; F. Stamen tube; G. The dorsal view of stamen, showing the teeth with stiff hairs at the apex of connective; H. The lateral view of stamen, showing the appendage of connective and the interstaminal gland; I. Pistil, showing stigmas, style and parietal placentas.