Ischaemum fieldingianum

HABIT Perennial. Culms erect; 60–100 cm long. Culm-nodes bearded. Leaf-sheaths glabrous on surface, or hirsute; with tubercle-based hairs. Leaf-sheath auricles erect. Ligule an eciliate membrane, or a ciliolate membrane; 1–2.5 mm long. Leaf-blade base cordate; with a brief petiole-like connection to sheath; petiole 0.1–0.2 cm long. Leaf-blades lanceolate; 10–20 cm long; 10–20 mm wide. Leaf-blade surface scaberulous; glabrous, or pubescent. Leaf-blade margins smooth, or scaberulous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 2; paired; appressed back to back; 5–11 cm long. Rhachis fragile at the nodes; angular; ciliate on margins. Rhachis internodes oblong; 4–5 mm long; 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; 4–5 mm long; 1 length of internode; ciliate.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; lanceolate; laterally compressed; 5–6 mm long; as long as fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; keeled; winged on keels (1 keel). Companion sterile spikelet lemmas 2; enclosed by glumes; 1-awned; with 6 mm long awn.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 5–6 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 obovate; 1 length of spikelet; coriaceous; much thinner above; 2-keeled; keeled all along; keeled laterally; winged on keel; winged narrowly; winged above; 5–7 -veined. Lower glume surface flat; glabrous, or pubescent. Lower glume margins ciliate. Lower glume apex acute. Upper glume lanceolate; 5–6 mm long; coriaceous; 1-keeled; 5 -veined. Upper glume surface asperulous; rough on veins. Upper glume apex acuminate.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret ovate; membranous; 3 -veined; pilose. Fertile lemma oblong; 4.8 mm long; membranous; without keel. Lemma margins ciliate. Lemma apex lobed; 2 -fid; incised 0.33 of lemma length; awned; 1 -awned. Principal lemma awn from a sinus; geniculate; 12.5 mm long overall. Palea 4.6 mm long. Palea keels scaberulous.

FLOWER Anthers 3; 2.8 mm long.

DISTRIBUTION Asia-tropical: Malesia.

NOTES Andropogoneae. Gilliland 1993.

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