Microstegium biaristatum (Steud.) Keng

Chen, H., Veldkamp, J. - F. & Kuoh, C. - S., 2012, Taxonomic revision of Microstegium s. str. Andropogoneae, Poaceae), Blumea 57 (2), pp. 160-189 : 162-164

1. Microstegium biaristatum (Steud.) Keng — Map 1

Microstegium biaristatum (Steud.) Keng (1932) 92. — Andropogon biaristatus Steud. (1854b) 379. — Type: Wallich Cat. 8823 p.p. (holo P; B, lost?, CAL?, microfiche IDC 7394; L).

Pollinia wallichiana Nees ex Steud. (1854b) 410. — Pollinia ciliata Trin. subsp. wallichiana (Nees ex Steud.) Hack. (1889) 177. — Pollinia ciliata Trin. var. wallichiana (Nees ex Steud.) Hack. (1899) 723. — Microstegium ciliatum (Trin.) A.Camus var. wallichianum (Nees ex Steud.) Honda (1930) 405. — Type: Wallich Cat. 8822 (holo P; BM, E, K, microfiche IDC 7394).

Andropogon formosanus Rendle (31 March 1904) 371. — Type: Henry 1167 (holo K; BM, MO).

Pollinia monantha Nees ex Steud.var. formosana Hack. (31 May 1904) 527. — Pollinia formosana (Hack.) Hayata (1918) 75, t. 44. — Microstegium formosanum (Hack.) A. Camus (1921) 201. — Pollinia ciliata Trin. var. formosana (Hack.) Honda (1925) 42. — Microstegium ciliatum (Trin.)A.Camus var. formosanum Honda (1930) 404. — Type: Matsumura s.n. (holo W).

Andropogon formosanus Rendle var. minor Rendle (1904) 372. — Type: Hance 10746 p.p. (holo BM; K).

[ Pollinia sp. near P.monantha : Merr.(1906) 327]. — Pollinia monantha Nees ex Steud. var. elmeri Hack. (1908) 167. — Microstegium elmeri (Hack.) A. Camus (1921) 200. — Pollinia glabrata (Brongn.) Trin.var. elmeri (Hack.) Merr. (1923) 34. — Type: Elmer 6524 (holo W).

Pollinia ciliata Trin.var. glabrata Ridl.(1925) 198. — Lectotype: Ridley 13861 (holo SING), designated here with assistance from Ms. S. Lee (SING).

Pollinia glaberrima Honda (1925) 42. — Microstegium glaberrimum (Honda) Koidz. (1929) 394. — Type: Soma s.n. 1914 (holo TI).

Pollinia sumatrensis Ridl. (1926) 94. — Type: SF 14788 (Boden Kloss) (holo K; SING).

Microstegium biforme Keng (1932) 91. — Type: B.C. Ching 8452 (holo N; US).

Microstegium ciliatum (Trin.) A.Camus var. integrum Ohwi (1942a) 157. — Microstegium ciliatum (Trin.) A.Camus subsp. integrum (Ohwi) T. Koyama (1987) 427, 516. — Type: Nagasawa 520 (holo KYO).

Microstegium ciliatum auct. non A.Camus.

Microstegium fasciculatum auct. non Henrard.

Pollinia ciliata auct. non Trin.

Pollinia grata auct. non Hack.

Perennials, mat-forming. Culms rambling, of moderate stature, 30–160 cm long, rooting from the lower nodes. Nodes glabrous. Sheaths glabrous, outer margin glabrous, oral hairs absent. Ligule a glabrous membrane, 0.5–2 mm long. Blades lanceolate to linear, 3–15 cm by 3–15 mm, firm, margins scabrous, apex acute to acuminate, glabrous to sparsely hairy on both sides, without tubercle-based hairs. Panicles 3–12 cm long, common axis 0.5–2 cm long. Racemes 3–20, digitate, ascending, straight, 3–10 cm long. Rachis semiterete, margins ciliate, internodes linear, 2.5–3.5 mm long. Sessile spikelets oblong to lanceolate, 2–4.5 mm long, callus setose. Lower glume oblong to lanceolate, chartaceous to coriaceous, midrib glabrous, dorsally longitudinally grooved, scaberulous, rough all over, glabrous, margins glabrous, apex obtuse, entire or dentate. Upper glume elliptic, back acute, glabrous, midrib glabrous, apex acute, muticous or awned, awn up to 4 mm long. Lower florets absent or present, reduced, barren. Upper lemma orbicular, c. 0.5 mm long, veined, apex incised to 0.2th of the lemma length, awn from a sinus, flexuous, column absent, awn 6–12 mm long. Upper palea present, ovate, c. 0.5 mm long, as long as the lemma, membranous. Anthers 3, 1–1.8 mm long. Pedicels linear, flattened, c. 2 mm long, margins pubescent. Pedicelled spikelets subequal to the sessile ones to variously reduced.

Distribution — India (Arunachal Pradesh, Assam, Bihar, Manipur, Meghalaya, Nagaland, Orissa, Tamil Nadu, Uttar Pradesh), Sri Lanka, Thailand (N: Chiang Mai; NE: Loei; Peninsular: Phangnga, Phattalung), Vietnam, S China (Fujian, Guangdong, Guanxi, Guizhou, Hainan, Hong Kong, Hunan, Jiangxi, Sichuan, Yunnan), Taiwan, Ryukyu Isl.; Malesia: Sumatra (E Coast, Padang), Malay Peninsula (Pahang, Penang, Perak, Selangor), Java (Bogor, Kediri, Kedu, Pasuruan, Priangan), Borneo (Kalimantan: B. Raya; Sabah), Philippines (Mindoro), Celebes (E, Minahasa), Lesser Sunda Islands ( Flores, Sumba, Wetar), New Guinea: Irian Jaya: Snow Mts, Enerotali; Papua New Guinea: Western, W Highlands, W Sepik, Central Prov.

Habitat — Open areas, grassland, on granitic boulders along river, moist slopes, along trail, in thickets, forest edge, always on good soil, 0–2300 m altitude.

Collector’s notes — Decumbent, scrambling, broadly erect, forming dense vegetation with few flowering culms, 0.3– 2 m. Lower stems brownish, rooting at the nodes; erect part green. Blades dark green above, dull green underneath. Inflorescence green, contracted, spike-like, racemes divergent to erect. Spikelets brownish, green, maroon. Anthers purplish. Stigmas white. Flowering at 9:30 a.m.

Notes — The name M. ciliatum has been used for the taxon which has flexuous awn from the apex of upper lemma since its basionym, Pollinia ciliata , was published. However, the type of M. ciliatum ( Pollinia ciliata ), Wallich 8815­B, is closer to M. fasciculatum actually and the legitimate name for this species should be M. biaristatum .

This species has been illustrated by Hsu (1975), Osada (1993), Liu (1997), and Chen & Phillips (2007: 832–836) as M. ciliatum .

Figures

Map 1 Distribution of Microstegium biaristatum (Steud.) Keng.