GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Ischaemum apricum

HABIT Perennial. Culms prostrate; 60–90 cm long; rooting from lower nodes. Culm-internodes 5–6 cm long. Culm-nodes pubescent. Lateral branches ample. Leaf-sheaths 5–6 cm long. Leaf-sheath oral hairs ciliate. Ligule a ciliolate membrane; 1.5 mm long. Leaf-blades 10–20 cm long; 4–5 mm wide. Leaf-blade surface pilose; sparsely hairy; hairy on both sides. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2; paired; appressed back to back; 4–8 cm long. Rhachis fragile at the nodes; angular; ciliate on margins. Rhachis internodes oblong; flat and forming a U or V shape with the pedicel in rear view. Rhachis internode tip transverse; cupuliform.

Spikelets in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels oblong; 1 length of internode; ciliate.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; elliptic; laterally compressed; 5.6 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; keeled; winged on keels; 9–11 -veined; rugose; muticous. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 5.8 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus pubescent; base truncate; inserted.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume oblong; 5.6 mm long; 0.8 length of spikelet; coriaceous; much thinner above; 2-keeled; keeled above; keeled laterally; winged on keel; winged moderately; winged above; 8–9 -veined. Lower glume surface convex; rugose; rough above. Lower glume apex dentate; 2 -fid. Upper glume ovate; 1 length of spikelet; coriaceous; 1-keeled; keeled above; winged on keel; 7 -veined. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn 3.5 mm long.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret lanceolate; 4.6 mm long; hyaline; 3 -veined. Fertile lemma lanceolate; 4.2 mm long; hyaline; without keel; 3 -veined. Lemma apex lobed; 2 -fid; incised 0.5 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 11 mm long overall; with twisted column. Column of lemma awn glabrous. Palea 3.8 mm long.

FLOWER Anthers 3; 2.2 mm long; yellow.

DISTRIBUTION Asia-tropical: Malesia.

NOTES Andropogoneae. Gilliland 1997.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.