glabrous. Sheaths ciliate along outer margin. Ligule densely awn up to 3 mm long, a fringe of longish hairs or wanting. Blades c. 9 cm by 6 mm, lanceolate, with rounded
or obtuse base and acute tip, with narrow, pale, thickened, scabrid or long-ciliate margin, scaberulous beneath or on both sides. Inflorescence up to 12 cm long, spike-
like panicle; panicle 2 – 3 cm, branches subsolitary with few short pedicelled spikelets. Spikelets obovate, obtuse, slightly longer than 2 mm long and as broad at maturity,
with pedicels c. 2 mm long. Glumes subequal, the lower in the closed spikelets slightly longer than the florets, in the mature spikelets usually as long as the florets,
distinctly 5 – 7-nerved, appearing apiculate or notched by inrolling of the margins when dry; upper glume usually obtuse, 5-nerved; both glumes glabrous or hairy
towards the tips; lemma subequal, the lower slightly longer, the upper distinctly pedicellate on the terete rhachilla. Caryopsis 1.3 mm long, yellowish brown.
Notes
Found in Malesia. According to Backer and Backhuizen 1968 and Jansen 1953, this species is variable in habit and size, and sometimes forming low cushions
on mountain-tops. Distribution
North: Tomohon, Alt. 700 m. Central: Taripa Poso.
Habitat
Marsh, volcanic area.
Specimen examined
Eyma 4046 BO, Koorders 19792 β BO.
50.11. Isachne stricta Elmer. Leafl. Philipp. Bot. 2: 463. 1908.
Plants perennial. Culms 30-90 cm long; slender. Blades 7-15 cm by 4-9 mm, firm, narrowly lanceolate, revolute when dry. Sheath loose, shorter than the
internodes, ciliate on margins. Ligule a row of hairs, about 2 mm long. Panicle 10-20 cm long, pyramidal, branches smooth, spreading when mature. Spikelets 1-1.2 mm
long, subglobose. Glumes similar, 7-9-nerved, equaling the spikelet or slightly shorter, glabrous, more or less hispid toward the apex. Florets monomorphic, globose to
elliptical-ovate, obtuse, glabrous or puberulent; rhachilla short, terete.
Notes
Found in Malesia – Philippines, Indonesia, and New Guinea.
Distribution at Sulawesi
Celebes. Habitat
Specimen examined Papa 109 WALL.
50.12. Isachne surgens P. Jansen. Reinwardtia 22: 281. 1953.
Plants perennial. Culms 80-100 cm long, geniculately ascending, rooting from lower nodes. Sheaths 15-80 cm long. Ligule absent. Blades 6-7 cm by 5-8 mm,
linear; blade nervation with 4-6 secondary nerves; surface scabrous, hairy abaxially. Inflorescence an open panicle. Panicle ovate, 4-5 cm long; primary branches
spreading, 1-2 cm long, capillary, flexuous, smooth. Spikelets solitary. Fertile spikelets pedicelled. Pedicels filiform. Fertile spikelets comprising 1 basal sterile
florets, 1 fertile florets, no rhachilla extension; oblong, dorsally compressed, 1.7 mm long, breaking up at maturity, disarticulating below each fertile floret. Glumes similar,
deciduous, shorter than spikelet, thinner than fertile lemma; lower glume oblong, 1.7 mm long, 1.1 length of upper glume, as long as spikelet, membraneous, apex obtuse;
upper glume oblong, 1.5 mm long, 0.9 length of spikelet, membraneous, no keels, 7- nerved, primary nerve obscure, surface glabrous, apex obtuse. Florets: basal sterile
floret male, with palea, separately deciduous; lemma oblong 1.7 mm long, 1.4 length of fertile lemma, as long as spikelet, chartaceous, 5-nerved, obscurely nerved,
glabrous, obtuse. Fertile florets bisexual, or female; lemma oblong, 1.2 mm long, coriaceous, no keel; lemma surface puberulous, margins involute, apex obtuse; palea
coriaceous, 2-nerved. Anthers 3. Caryopsis with adherent pericarp.
Notes
Found in Malesia.
Distribution
South: Peak of Bonthain, Alt. c. 2800 m.
Habitat
Opened area.
Specimen examined
Bunnemeijer 11268 BO, holotype.
Tribe 13. ORYZEAE Dumort. Observ. Gramin. Belg. 83, 89, 135. 1824. Type:
Oryza L. Sp. Pl. 1: 333. 1753.
Chikusichloinae Honda. J. Fac. Sci. Univ. Tokyo, Sect. 3, Bot. 330. 1930. Luziolinae Terrell H. Rob. Bull. Torrey Bot. Club 1015: 244. 1974.
Oryzeae Kunth. Enum. Pl. 1: 5. 1833. Zizaiinae Benth. J. Linn. Soc., Bot. 19115, 116: 54. 1881.
Plants annual, or perennial. Blades usually linear, rarely elliptic. Ligule membraneous. Inflorescence a panicle, occasionally with simple racemelike primary
branches. Spikelets with 1 floret, laterally compressed, rachilla extension absent, falling entire. Glumes absent, or reduced to small scales at the base of floret; lemma
membraneous to leathery, keeled, 5-10-nerved, entire, with or without a straight awn from apex; palea resembling lemma, but narrower, 3-7-nerved with central keel.
Lodicules 2. Stamen usually 6. Caryopsis linear to ovoid.
Key to the Genera
1.a. Pedicels linear; fertile spikelets comprising 2 basal sterile floret, 1 fertile floret; spikelets elliptic, ovate, or orbicular; callus glabrous, base truncate
……………………………………………………………………...64. Oryza
b. Pedicels oblong; fertile spikelets comprising 1 fertile florets; spikelets linear, or
lanceolate; callus brief, or oblong, base obtuse………………..52. Leersia
Genus description and the species and variety 52.
LEERSIA Sol. ex Swartz. nom. typ. cons. Type: Leersia oryzoides L. Sw.
Prodr. 1, 21. 1788. Aplexia Raf. Neogenyton 4. 1825; Kew Bull., Addit. Ser. 13: 1-389. 1986.
Blepharochloa Endl. Gen. Pl. 1352. 1840.
Commemorating J.D. Leers 1727-1774, German physician and botanist. About 18 species, Europe, Africa, Asia, and America. Plants annual, or
perennial. Slender grasses of standing water or wet ground. Inflorescence a lax panicle. Glumes virtually suppressed. Floret 1. Lemmas: lower absent, upper 5-
nerved, lateral nerves close to the edge, median nerve bristly, the whole boat-shaped and fitting the palea to enclose the flower. Palea narrower and of similar texture, 3-
nerved, similary bristly. Stamens 6.
52.1. Leersia hexandra Swartz. Prodr. 21. 1788.
