Hackelochloa porifera

HABIT Annual. Culms erect; 50–100 cm long. Culm-nodes glabrous. Lateral branches fastigiate. Leaves cauline. Leaf-sheaths loose, or inflated; hirsute; with tubercle-based hairs. Ligule a ciliolate membrane. Leaf-blade base broadly rounded, or cordate. Leaf-blades linear, or lanceolate; 5–20(–25) cm long; 5–10 mm wide. Leaf-blade surface glabrous, or pilose; sparsely hairy, or moderately hairy; with tubercle-based hairs. Leaf-blade margins scabrous.

INFLORESCENCE Synflorescence compound; scanty. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; exserted, or embraced at base by subtending leaf. Spatheole linear, or lanceolate.

Racemes 1; single; 15–40 cm long. Rhachis fragile at the nodes; flattened. Rhachis internodes oblong; 1.5–2 mm long; adherent to upper glume of sessile spikelet. Rhachis internode tip transverse; crateriform.

Spikelets appressed; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels fused to internode; united wholly; oblong.

STERILE SPIKELETS Companion sterile spikelets well-developed; containing empty lemmas, or male; lanceolate, or elliptic; asymmetrical; dorsally compressed; 3–3.5 mm long; longer than fertile; deciduous with the fertile. Companion sterile spikelet glumes herbaceous; winged on keels; 5–7 -veined; pitted; smooth; glabrous; entire; obtuse to 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 oblong; dorsally compressed; 1.5–2(–2.5) mm long; falling entire; deciduous with accessory branch structures. Spikelet callus base truncate; with central peg; attached transversely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume orbicular; 1 length of spikelet; indurate; without keels. Lower glume surface areolate. Lower glume apex obtuse. Upper glume oblong; cartilaginous; without keels; 3 -veined. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret ovate; hyaline; 0 -veined; without midvein; without lateral veins; obtuse. Fertile lemma ovate; 1 mm long; hyaline; without keel; 0 -veined. Lemma apex obtuse, or acute. Palea hyaline; 0 -veined; without keels.

FLOWER Lodicules 1; cuneate; 0.2–0.3 mm long.

DISTRIBUTION Asia-temperate: China. Asia-tropical: India and Indo-China.

NOTES Andropogoneae. TB.

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