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.

Chionachne punctata

HABIT Annual. Culms decumbent; 50–100 cm long; 1–3 mm diam.; rooting from lower nodes. Culm-internodes distally glabrous. Culm-nodes pubescent. Leaf-sheaths 3–14.2 cm long; glabrous on surface, or pilose; with tubercle-based hairs. Leaf-sheath auricles absent. Ligule an eciliate membrane; 1–2 mm long. Leaf-blades linear; 20–70 cm long; 6–15 mm wide. Leaf-blade venation with 6–10 secondary veins. Leaf-blade surface glabrous, or pilose; with tubercle-based hairs. Leaf-blade margins cartilaginous; scaberulous.

INFLORESCENCE Monoecious; with male and female spikelets in the same inflorescence. Inflorescence composed of racemes; axillary; subtended by a spatheole; embraced at base by subtending leaf. Spatheole linear; 1.7–2.8 cm long; herbaceous. Peduncle widened at apex.

Racemes 1; single; unilateral; 1.1–2.7 cm long; bearing few fertile spikelets; bearing 1–2 fertile spikelets on each (and 2(-6) male almost enfolded by topmost female spikelet). Rhachis fragile at the nodes; subterete; glabrous on surface. Rhachis internodes linear; 3–5 mm long; bearing a sterile companion laterally. Rhachis internode tip cupuliform.

Sexes segregated; on bisexual branches; with male above. Spikelets embracing internode; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Male spikelets sessile and pedicelled; 2 in a cluster. Pedicels free.

STERILE SPIKELETS Companion sterile spikelets rudimentary; shorter than fertile; deciduous with the fertile.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 9–11 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 oblong; 1 length of spikelet; coriaceous; without keels; winged on margins; winged near apex. Lower glume surface smooth; transversely waisted; glabrous. Lower glume apex emarginate. Upper glume elliptic, or ovate; 6–8 mm long; herbaceous, or coriaceous; without keels; 9–15 -veined. Upper glume apex acute.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret elliptic, or ovate; 5–6.5 mm long; hyaline; 3 -veined; acute. Fertile florets female. Fertile lemma lanceolate, or oblong, or ovate; 5–5.5 mm long; hyaline; without keel. Lemma apex acute. Palea present; lanceolate, or oblong, or ovate; 4–4.5 mm long; hyaline.

FRUIT Caryopsis with adherent pericarp; 2.5–3.5 mm long. Hilum punctiform.

MALE Male spikelets resembling female; with pedicels fused to rhachis; obovate (orbicular); 4–6.5 mm long. Male spikelet glumes 2; 16 -veined.

DISTRIBUTION Asia-tropical: Indo-China and Malesia.

NOTES Andropogoneae. Jannik & Veldkamp 2004.

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