Arundinella mesophylla

HABIT Annual. Culms geniculately ascending, or decumbent; slender; 20–45 cm long. Culm-nodes glabrous. Leaf-sheaths glabrous on surface, or pilose; with tubercle-based hairs. Ligule a ciliolate membrane; 1 mm long. Leaf-blades 5–10 cm long; 4–6 mm wide. Leaf-blade surface pilose; hairy on both sides; with tubercle-based hairs. Leaf-blade margins scaberulous; tuberculate-ciliate. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence a panicle; bearing juvenile spikelets at emergence.

Panicle open; elliptic, or ovate; 4–12 cm long; 2 cm wide; contracted about primary branches. Primary panicle branches 0.5–1.8 cm long. Panicle axis glabrous, or villous. Panicle branches glabrous, or villous.

Spikelets in pairs. Fertile spikelets pedicelled; 2 in the cluster. Pedicels glabrous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 5–5.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus pubescent; obtuse.

GLUMES Glumes persistent; dissimilar; exceeding apex of florets; thinner than fertile lemma; gaping. Lower glume lanceolate; 4 mm long; 0.75 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume surface pilose; with tubercle-based hairs. Lower glume apex setaceously attenuate. Upper glume lanceolate; 5.5 mm long; 2.75 length of adjacent fertile lemma; membranous; 1-keeled; 5 -veined. Upper glume surface pilose; with tubercle-based hairs. Upper glume apex entire, or dentate; 2 -fid; acuminate.

FLORETS Basal sterile florets male; with palea; persisting on inflorescence. Lemma of lower sterile floret similar to upper glume; elliptic; 2.5 mm long; membranous; 1-keeled; 3 -veined; acute. Fertile lemma oblong; 2 mm long; coriaceous; without keel; 5 -veined. Lemma lateral veins obscure. Lemma surface asperulous. Lemma margins involute; interlocking with palea keels. Lemma apex dentate; 2 -fid; awned; 3 -awned. Principal lemma awn from a sinus; geniculate; 6 mm long overall; with twisted column. Column of lemma awn 3 mm long. Lateral lemma awns arising on apex of lobes; 2.5 mm long. Palea with auriculate flaps; coriaceous; 2 -veined. Palea surface asperulous.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 0.5–1.75 mm long. Stigmas 2.

FRUIT Caryopsis with adherent pericarp. Hilum punctiform.

DISTRIBUTION Asia-tropical: India.

NOTES Arundinelleae. Bor 1993.

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