Arundinella setosa

HABIT Perennial. Rootstock evident. Butt sheaths glabrous, or woolly. Culms 50–100 cm long. Culm-nodes glabrous. Leaf-sheaths glabrous on surface, or pilose. Ligule a ciliolate membrane. Leaf-blades 10–25 cm long; 2–5 mm wide. Leaf-blade surface glabrous to hirsute. Leaf-blade margins glabrous, or ciliate. Leaf-blade apex attenuate.

INFLORESCENCE Inflorescence a panicle; bearing juvenile spikelets at emergence.

Panicle open; oblong, or ovate; nodding; 5–30 cm long; contracted about primary branches. Primary panicle branches 1–15 cm long. Panicle axis smooth, or scabrous.

Spikelets solitary, or in pairs. Fertile spikelets pedicelled; 1–2 in the cluster. Pedicels scabrous; bearing a few hairs; hairy at tip.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 5–7 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 elliptic; 3.5–5 mm long; 0.6–0.7 length of upper glume; membranous; 1-keeled; 3 -veined. Lower glume surface scabrous; rough on veins. Lower glume apex acuminate; awned; 1 -awned. Upper glume elliptic; 5.5–7 mm long; 2 length of adjacent fertile lemma; membranous; 1-keeled; 5 -veined. Upper glume surface scabrous; rough on veins. Upper glume apex caudate.

FLORETS Basal sterile florets male, or barren; with palea; persisting on inflorescence. Lemma of lower sterile floret similar to upper glume; elliptic; 3–4.5 mm long; membranous; 1-keeled; 5 -veined; obtuse. Fertile lemma lanceolate; 2.5–3 mm long; coriaceous; dark brown; 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; 5–9.5 mm long overall; with twisted column. Column of lemma awn 3.5 mm long. Lateral lemma awns arising on apex of lobes; 2–3.5 mm long. Palea with auriculate flaps; coriaceous; 2 -veined. Palea surface asperulous.

FLOWER Lodicules 2; cuneate; fleshy. Anthers 3; 1.5 mm long. Stigmas 2.

FRUIT Caryopsis with adherent pericarp. Embryo 0.6 length of caryopsis. Hilum punctiform.

DISTRIBUTION Asia-temperate: China and eastern Asia. Asia-tropical: India, Indo-China, Malesia, and Papuasia. Australasia: Australia.

NOTES Arundinelleae. Bor 1993.

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