Liparis tianchiensis (Orchidaceae), a new species from Gansu, China Author Liu, Xiao-Juan College of Forestry, Gansu Agricultural University, Lanzhou 730070, Gansu, China liuxiaojuan@gsau.edu.cn Author Sun, Xue-Gang College of Forestry, Gansu Agricultural University, Lanzhou 730070, Gansu, China text PhytoKeys 2023 2023-01-23 219 27 33 http://dx.doi.org/10.3897/phytokeys.219.90351 journal article http://dx.doi.org/10.3897/phytokeys.219.90351 1314-2003-219-27 A2D37C7087D65E19A8B0421EFD7AF8C8 Liparis tianchiensis X.J.Liu & X.G.Sun sp. nov. Figs 1 , 2 Type . China . Gansu Province , Longnan City , Wenxian County , Tianchi Lake , growing on moss in evergreen broad-leaved forest, elev. 1680 m , 15 July 2021 , X.J. Liu & H. Lin , WX20210715001 ( holotype : GAUF!, isotype: GAUF!) . Diagnosis. Liparis tianchiensis is similar to L. damingshanensis with single small leaf, erect, lax flowered-inflorescences, small greenish purple flowers, spreading sepals, free reflexed and linear petals, a lip with 2 calli near the base and an arcuate column. It, however, differs from the latter by having a longer dorsal sepal (9.0-11.0 mm vs 6.0-8.0 mm) and a longer (8.0-10.0 vs 5.0-7.0 mm) and oblong (vs obovate-triangular) lip. Description. Terrestrial herbs. Pseudobulbs ovoid or oblong-ovoid, 0.5-1.5 cm long, 0.4-1.0 cm in diameter, covered with white membranous remnant sheaths. Leaf single, green, glabrous, petiole sheath like, 0.5-1.0 cm long, amplexicaul, not articulate; blade ovate, 1.2-3.0 cm x 1.0-2.0 cm, contracted and decurrent into petiole at base and acute or obtuse at apex, margin entire and flat or slightly undulate. Inflorescence 4.0-9.0 cm long; peduncle slightly compressed cylindrical, narrowly winged on either side; rachis laxly 2-4-flowered; floral bracts ovate-triangular, 2.0-3.0 mm long, membranous, greenish-white. Flowers fully opening, greenish-purple, 1.6-2.2 cm across; pedicel and ovary greenish-purple, twisted, 1.0-1.2 cm long. Dorsal sepal ovate-oblong, margins often revolute, apex obtuse, 9.0-11.0 mm x ca. 1.0 mm, translucent greenish-white. Lateral sepals parallel under the lip, obliquely ovate-elliptic, margins often revolute, apex obtuse, 8.0-11.0 mm x ca. 1.0 mm, translucent greenish-white. Petals deflexed, narrowly oblong-falcate, margins revolute, 8.0-10.0 mm x 0.3-0.5 mm, purple. Lip oblong, 8.0-10.0 mm x 3.0-5.0 mm, pale purple, with 2 short longitudinal triangular lamellae at the shallowly concave base, mucronate at apex; mid-vein dull-purple, broad and stout, conspicuous from the base up to the apex. Column conspicuously incurved, 4.0-5.0 mm long, ca. 1 mm in diameter, apex with 2 short, triangular wings, base purple and swollen; anther-cap obovate, glabrous; pollinia four in two pairs, yellow. Fruit not observed. Etymology. The specific epithet is derived from the type locality Tianchi Lake, Wenxian County, Gansu Province, China. Distribution and habitat. Liparis tianchiensis is terrestrial and grows in shaded and damp moss-covered areas in evergreen broad-leaved forest, forming scattered colonies on the slopes of Tianchi Lake at 1680 m a.s.l. For the time being, Liparis tianchiensis is only known from the type locality. The subpopulation is small, with less than 200 individuals. Figure 1. Liparis tianchiensis sp. nov. A habit B non-flowering plants in situ C flowering individual D dissected floral parts E leaf, adaxial view F leaf, abaxial view G flower, lateral view. Scale bars: 10 cm ( B ); 1 cm ( C-G ). Figure 2. Liparis tianchiensis sp. nov. A individual in bloom B flower, lateral view C dorsal sepal D lateral sepal E petal F pedicel, ovary and column G lip H anther-cap, abaxial view I anther-cap, adaxial view. Scale bars: 1 cm ( A, B ); 0.5 cm ( C-G ); 1 mm ( H, I ). Drawn by Hui Lin from the holotype. Flowering phenology. June and July.