2. 中国科学院东南亚生物多样性研究中心, 叶津, 内比都, 缅甸;
3. 白雪山国家公园管理局, 葡萄, 克钦邦, 缅甸
2. Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences, Yezin, Nay Pyi Taw 05282, Myanmar;
3. Hkakarborazi National Park, Putao, Kachin State, Myanmar
The monocot family Triuridaceae consists of approximate 11 genera and ca. 50 species and is widespread in tropical and subtropical region around the world[1-2]. Triuridaceae is characterized by achlorophyllous plants, leaves alternate, reduced and scalelike, small flowers actinomorphic, sometimes appendaged at apex, stamens 2-6 inserted at base of receptacle or perianth, carpels 6 to many, ovule solitary, fruiting carpels crowded, opening by a slit[1, 2].
During our botanic survey in northern Myanmar, Sciaphila nana, a species representing a new familial record of flora of Myanmar, was discovered and here described below.
Sciaphila nana Blume, Mus. Bot. 1: 322. 1851, Meerendonk in Fl. Males. Ⅰ. 10: 117. 1984. Fig. 1.
Terrestrial herbs, mycotrophic, plants violet. Stems delicate, erect, 5-10 cm long, ca. 0.5 in diam., glabrous. Leaves scale-like, entire, concave and appressed to stem, ovate-lanceolate, acute, 2-2.2 mm long, 1 mm wide. Inflorescences raceme, ca. 2 cm long; bracts lanceolate, ca. 1.5 mm long, pedicel about 1.5-2 mm long. Flowers unisexual, approximately 7-to 10-flowered, male flowers above, female ones below, sometime mixed. Male flowers about 2 mm in diam.; 6 tepals, outer 3 larger than inner 3; the larger tepals oblong, 1.5 mm long, 0.5 mm wide; inner tepals 0.8-1 mm long, with ellipsoid knob at apex; stamens 3, filaments 0.2 mm long, anthers 4-celled. Female flowers ca. 2 mm in diam.; pedicel 2.5-3 mm long; tepals 3, oblong, ca. 1 mm long, ca. 0.6 mm wide, oblong, acute; carpels 30-40, ovate; style awl-shaped, 0.5 mm long, inserted laterally near the top, apex acute.
Distribution. Indonesia, Malaysia, Myanmar (new record), Philippines, Thailand, Vietnam.
Ecology. Growing on soil, under humid seasonal tropical rainforest, ca. 500 m in altitude.
Flowering Period: April to May.
Specimens examined. Myanmar. Kachin State, Putao County, Maojiaowan Village, Jin X. H., Zhu X. Y. & Han M. Q. PT-6990, May 21, 2017 (PE).
Sciaphila nana is rare but widespread species in Southeast Asia[4-6]. It is readily distinguished from its Asian relatives by monoecious plants (plants with bisexual flowers in S. maculata and S. tenella), tepals of female flowers entire (long hairs in S. arcuata), anther 4-celled (1-celled in S. stellata, 2-celled in most other species, such as S. jingfenglingensis), inner tepals of male flowers with stipulate knob (all tepals of male flowers with stipulate knob in S. arfakiana), style awl-shaped (club-shaped in S. secudiflora)[4-10].
Sciaphila nana is closely related to S. khasiana Benth. & Hook. f. from Bangladesh by sharing small status plants, racemose inflorescence and four-celled anthers, but differs from the latter by its flowers with 6 tepals (4-5 tepals in S. khasiana), monoecious plants (dioecious in S. khasiana), and male flowers usually without subulate pistillodes (3 in male flowers of S. khasiana).
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