Iseilema maculatum

HABIT Annual. Basal innovations flabellate. Culms erect; 25–40 cm long. Culm-internodes distally glabrous. Leaf-sheaths keeled. Ligule a ciliolate membrane; 1 mm long; ciliate from base of abaxial surface; obtuse. Leaf-blades conduplicate; 1.5 mm wide; flaccid. Leaf-blade surface glabrous; hairless except near base.

INFLORESCENCE Synflorescence compound; scanty; 8–20 cm long. Inflorescence composed of racemes; terminal and axillary; deciduous as a whole; subtended by a spatheole; enclosed. Spatheole lanceolate; 1–1.5 cm long; herbaceous; without tubercles; glabrous. Peduncle 1 cm long; pilose above (at tip).

Racemes 1; single; oblong; bearing few fertile spikelets; bearing 1 fertile spikelets on each. Raceme-bases brief (truncate).

Spikelets in threes (basal paired). Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 2 in the cluster. Pedicels filiform; 2.5–3 mm long; ciliate.

STERILE SPIKELETS Basal sterile spikelets well-developed; 4 in number; forming an involucre about the fertile; with both pairs arising at about the same level; pedicelled; deciduous with the fertile; male; elliptic; 4 mm long; equalling fertile. Basal sterile spikelet glumes herbaceous.

Companion sterile spikelets well-developed; male; lanceolate; 4.5 mm long; longer than fertile; separately deciduous. Companion sterile spikelet glumes cartilaginous; glabrous; ciliolate on margins; muticous. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 4 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes dissimilar; firmer than fertile lemma; shiny. Lower glume lanceolate; 1 length of spikelet; cartilaginous; without keels; keel-less except near apex. Lower glume surface convex. Lower glume apex dentate; 2 -fid. Upper glume lanceolate; 1 length of spikelet; coriaceous; 3 -veined. Upper glume apex acuminate.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret hyaline. Fertile lemma linear; 2 mm long; hyaline; 1 -veined. Lemma apex lobed; 2 -fid; awned; 1 -awned. Principal lemma awn geniculate; 10–20 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Anthers 3; 2 mm long; purple.

DISTRIBUTION Asia-tropical: Malesia.

NOTES Andropogoneae. Jansen 2001.

ADDITIONAL CHARACTERS Basal sterile spikelet glumes purple spotted; companion sterile spikelet glumes purple spotted.

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