GrassBase - The Online World Grass Flora

Descriptions

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

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

Iseilema eremaeum

HABIT Annual; caespitose. Culms erect, or geniculately ascending; 5–20 cm long; 1 -noded. Leaf-sheaths longer than adjacent culm internode; eglandular; keeled. Ligule a ciliolate membrane; 0.7–0.9 mm long. Leaf-blades linear, or lanceolate; conduplicate; 2–6 cm long; 1–4 mm wide; light green. Leaf-blade margins scaberulous. Leaf-blade apex acute.

INFLORESCENCE Synflorescence compound; paniculate; 2–10 cm long. Inflorescence composed of racemes; terminal and axillary; deciduous as a whole; subtended by a spatheole; enclosed. Spatheole lanceolate; 0.6–1 cm long; membranous; without tubercles, or tuberculate (on keel). Peduncle 0.1–0.2 cm long; tuberculate above.

Racemes 1; single; oblong; 0.7–0.8 cm long; bearing few fertile spikelets; bearing 1 fertile spikelets on each. Rhachis pilose on surface. Rhachis hairs 2.5–3 mm long. Rhachis internodes linear; 0.5–1 mm long. Raceme-bases brief (truncate); pilose; with 3 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; 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. Basal sterile spikelet pedicels linear; 1.5 mm long. Basal sterile spikelets male; elliptic; 3–4 mm long; smaller than fertile. Basal sterile spikelet glumes coriaceous; smooth, or scaberulous; smooth on margins, or tuberculate on margins.

Companion sterile spikelets well-developed; male; lanceolate; 2–3 mm long; shorter than fertile; separately deciduous. Companion sterile spikelet glumes membranous; 7–9 -veined; smooth, or tuberculate (on keels); glabrous; acute; 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; acuminate; 5–5.5 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes dissimilar; firmer than fertile lemma. Lower glume elliptic; 1 length of spikelet; coriaceous; without keels; keel-less except near apex; 8 -veined. Lower glume surface pubescent; hairy above. Lower glume apex emarginate. Upper glume lanceolate; 1 length of spikelet; coriaceous; 3 -veined.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret ovate; 2.9–3.3 mm long; hyaline; 0 -veined; without midvein; without lateral veins; obtuse. Fertile florets female. Fertile lemma linear; 3.5 mm long; membranous; 1 -veined. Lemma apex entire; awned; 1 -awned. Principal lemma awn geniculate; 13–16 mm long overall; with twisted column. Column of lemma awn glabrous. Palea absent or minute.

FRUIT Caryopsis ellipsoid; 2.5 mm long.

DISTRIBUTION Australasia: Australia.

NOTES Andropogoneae. Blake.

ADDITIONAL CHARACTERS Basal pedicels glabrous.

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