Iseilema holmesii

HABIT Annual. Culms erect; slender; 20–40 cm long; 1–2 -noded. Culm-nodes glabrous. Leaf-sheaths keeled; glabrous on surface. Ligule a ciliate membrane; 0.6–0.8 mm long. Leaf-blades flat, or conduplicate; 6–13 cm long; 4–5 mm wide. Leaf-blade surface scaberulous; rough on both sides. Leaf-blade margins tuberculate-ciliate. Leaf-blade apex acute.

INFLORESCENCE Synflorescence compound; scanty; 2–10 cm long. Inflorescence composed of racemes; terminal and axillary; deciduous as a whole; subtended by a spatheole; enclosed. Spatheole lanceolate, or elliptic; 1.2–1.5 cm long; herbaceous; tuberculate (on midnerve). Peduncle 0.3–0.7 cm long; scaberulous above.

Racemes 1; single; oblong; 0.7–0.8 cm long; bearing few fertile spikelets; bearing 1 fertile spikelets on each. Rhachis internodes filiform; 1.7–1.9 mm long (below fertile spikelet). Raceme-bases brief (truncate); pilose; with 0.5 mm long hairs.

Spikelets in threes (basal paired). Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 2 in the cluster. Pedicels filiform; 1.9–2 mm long; pubescent.

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. Basal sterile spikelet pedicels oblong; 0.4–0.7 mm long. Basal sterile spikelets barren, or male; elliptic, or oblong; 4.5–5 mm long; larger than fertile. Basal sterile spikelet glumes herbaceous; scabrous on margins and ciliate on margins.

Companion sterile spikelets well-developed; containing empty lemmas; lanceolate; 3.2–3.3 mm long; shorter than fertile; separately deciduous. Companion sterile spikelet glumes chartaceous; 7 -veined; scaberulous and tuberculate; glabrous; 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. Spikelet callus pilose. Spikelet callus hairs 1.2 mm long.

GLUMES Glumes dissimilar; firmer than fertile lemma. Lower glume elliptic; 1 length of spikelet; coriaceous; without keels; keel-less except near apex. Lower glume primary vein scaberulous. Lower glume surface asperulous; rough above. Lower glume apex truncate. Upper glume lanceolate; 1 length of spikelet; coriaceous; 3 -veined.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret hyaline. Fertile florets female. Fertile lemma linear; 3 mm long; membranous; 1 -veined. Lemma apex entire; awned; 1 -awned. Principal lemma awn geniculate; 22–24 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FLOWER Anthers 3; 3 mm long.

DISTRIBUTION Australasia: Australia.

NOTES Andropogoneae. Blake.

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