A new species of Ischaemum Linn. (Poaceae) from Kerala, India

Ischaemo commutato Hackel affinis sed pilis calli 1-2 mm longis, glumis inferioribus spicularum sessilium distincte 11-13-nervosis ovato-lanceolatis breviter acuminatis omnino chartaceis sine nodulis, carinis non alatis, flosculis inferioribus cassis, spiculis pedicellatis plerumque redactis differt. – Typus: Sreekumar 71863 (CAL; iso K, MH), India, Kerala State, Idukki District, Eravikulam National Park, c. 2200 m alt., 7-4-1980. Tufted annuals or perennials. Culms 10—30 cm high, erect; nodes glabrous. Leaves linear-lanceolate, 2—10 by 0.4—0.6 cm, shortly acuminate, narrowed and tapering at the base, sparsely villous with tubercle-based hairs. Sheaths 2—8 cm long, equal to or shorter than the internodes, striate, villous with sparse tubercled hairs, throat sparsely villous. Ligule 2—3 mm long, ovate, acute, membranous. Racemes 2 or 3, 2—6 cm long, stout; spathe 2—10 cm long, glabrous. Joints of racemes linear, turbinate, 3.5— 4 mm long, coriaceous, long villous along the margins and dorsal angle. Sessile spikelets ovate-lanceolate, 6—7 mm long; callus densely bearded, hairs 1-2 mm long. Lower glume ovate-lanceolate, 6-6.5 by 1.75—2 mm, acuminate, without nodules, chartaceous, distinctly 11—13-nerved, with a few long hairs on dorsal side towards base, margin narrowly and evenly inturned, not winged, scabrid in the upper half; upper glume 5.5—6 by 1.25—1.5 mm, boat-shaped or ovate-lanceolate when spread, acuminate, keels rounded except towards the minutely winged and scabrid apex, chartaceous, 3—5-nerved, covered with very short adpressed hairs, especially towards the base, margins infolded and ciliate in the upper half. Lower floret empty. Upper floret bisexual. First lemma lanceolate, 4.5—5 by 1—1.5 mm, delicate, hyaline, faintly 3-nerved, margins infolded and ciliate in the upper half, glabrous elsewhere. Second lemma lanceolate, 4—4.5 by 1—1.5 mm, delicate, hyaline, faintly 3-nerved, margins ciliolate in the upper half, apex notched, lobes acute. Awn 10—12 mm long, geniculate, column 5—6 mm long, chestnut brown, arista pale, scabrid. First palea elliptic-lanceolate, 4-4.5 by 1-1.25 mm, delicate, hyaline, 2-keeled, margins infolded and ciliate in the upper half. Second palea oblong, 3—4 by 0.75—1 mm, delicate, hyaline, 2-keeled, glabrous, apex rounded. Lodicules of upper floret obovate, 0.6—0.75 by 0.4—0.5 mm, retuse at apex, faintly 5—7-nerved, median nerve prominent. Lodicules of lower floret obovate, oblique, c. 1 by 0.5 mm, faintly 3-5-nerved, apex wavy and 2 horned. Stamens 3, anthers 1.5—2 mm long. Caryopsis obovate with 2 horns at apex, c. 2 by 0.75 mm. Pedicelled spikelet ovate-lanceolate, 4—6 mm long, unawned, usually reduced, sterile. Pedicels linear, turbinate, 3-4 mm long, villous along the margins and dorsal angle, hairs 0.5—2 mm long. Lower glume ovate-lanceolate, 4.5-6 by 1.25-1.5 mm, winged on one margin, wing scabrid, smooth, chartaceous, faintly 9—11-nerved, glabrous, margins inturned, scabrid towards sharply at apex; upper glume ovate-lanceolate, 3-5 mm long, keel rounded, glabrous, apex acute. Florets empty.