Microstegium glabratum (Brongn.) A.Camus

Chen, H., Veldkamp, J. - F. & Kuoh, C. - S., 2012, Taxonomic revision of Microstegium s. str. Andropogoneae, Poaceae), Blumea 57 (2), pp. 160-189 : 173-176

9. Microstegium glabratum (Brongn.) A.Camus — Fig. 7; Map 8

Microstegium glabratum (Brongn.) A. Camus (1921) 201; Hosok. (1934) 663, isonym. — Eulalia glabrata Brongn. (1831) 93. — Pollinia glabrata (Brongn.) Trin.(1836) 70. — Andropogon glabratus (Brongn.) Steud.(1840) 91, non Roxb. [Herb. Roxburgh in Wallich Cat. 8805­A (in syn.; microfiche IDC 7394)]. — [ Pogonatherum glabratum (Brongn.) Roberty (1960) 388, nom. inval.]. — Type: Dumont d’Urville s.n. ‘Borabora’ (holo P).

Nemastachys taitensis Steud.(1854b) 357. — Microstegium taitense (Steud.) A. Camus (1921) 201. — Type: Dumont d’Urville s.n. ‘Taiti’ (holo P).

Pollinia gracillima Hack. (1889) 179. — Eulalia gracillima (Hack.) Kuntze (1891) 775. — Microstegium gracillima (Hack.) A. Camus (1921) 201. — Type: Anon. (holo G) sub ‘ Leptatherum royleani’, Tahiti.

Pollinia monantha Nees ex Steud.var. leptathera Hack.(1908) 167. — Type: Merrill 5212 (holo W, not found; L, P).

Pollinia glabrata (Brongn.) Trin.var. luzonensis Hack., Kneucker Exsicc. 785 (1914); Allg. Bot. Z. Syst. 20 (1915) 143. — Type: Kneucker Exsicc. 785 (Fénix & Ramos) (holo KR, lost; BM, K, L, WAG).

Microstegium nudum auct. non A.Camus.

Annuals, mat-forming. Culms rambling, weak, 25 – 60 cm long, rooting from the lower nodes. Nodes glabrous. Sheaths glabrous, outer margin glabrous or hairy, oral hairs scanty or absent. Ligule a glabrous membrane, 0.5–0.8 mm long. Blades lanceolate, 5 –16 cm by 2 –10 mm, flaccid, base attenuate to slightly rounded, pseudopetiole absent, margins scaberulous, apex acute to acuminate, glabrous or sparsely puberulous on both sides, without tubercle-based hairs. Panicles 4–10 cm long, common axis 0.5–1 cm long. Racemes 4–11, digitate, ascending, straight, 4–9 cm long. Rachis fragile, flattened, margins glabrous, internodes linear, 2.5–3.5 mm long. Sessile spikelets without a short stalk, deciduous with the adjacent joint and pedicel, oblong to lanceolate, 2.5–3 mm long, callus glabrous or puberulous. Lower glume oblong, coriaceous, midrib glabrous, dorsally longitudinally grooved, smooth, glabrous, margins glabrous, apex obtuse, entire. Upper glume elliptic, back acute, glabrous, midrib ciliate, apex entire, attenuate, mucro c. 0.5 mm long. Lower florets absent. Upper lemma oblong, 0.5–1 mm long, without veins, glabrous, apex entire, awn flexuous, column absent, 10–15 mm long. Upper palea ovate, 0.5–1 mm long, as long as the lemma, membranous, apex entire. Anthers 3, 0.7–1 mm long. Pedicels linear, flattened, 2–2.5 mm long, margins glabrous. Pedicelled spikelets subequal to the sessile ones.

Distribution — Malesia: Philippines (Luzon, Mindanao, Mindoro, Samar), Sabah, Borneo, Lesser Sunda Islands, Mela- nesia, Micronesia: Palau, Mariana Islands. Polynesia: New Caledonia, Vanuatu, Fiji, Samoa, Tahiti, Bora Bora, Raiatea. China (Hainan Island). Taiwan. Japan (S Ryukyu Islands).

Habitat — Forming dense vegetation, shaded, humid places, in fringe of wood, limestone, on serpentine, red clay, near brook, 80–1500 m altitude.

c d 1 mm 1 mm 1 mm b 2 cm e 1 mm f g h 1 mm a 1 mm j

i

Note — Apparently not in India (i.e. not mentioned by Sur 1985) although Wallich mentioned specimens in the Roxburgh herbarium. The line drawing of this species ( Fig. 7) has been published previously ( Chen et al. 2011a).

Figures

Map 8 Distribution of Microstegium glabratum (Brongn.) A.Camus.