Arthrostylidium simpliciusculum

HABIT Perennial; caespitose. Rhizomes short; pachymorph. Culms leaning; slender; 1000–1200 cm long; woody. Culm-internodes terete; with small lumen. Lateral branches dendroid. Branch complement many; in a clump; subtended by a bare patch above the node. Ligule a ciliolate membrane. Collar with external ligule. Leaf-blade base with a brief petiole-like connection to sheath; petiole 0.1–0.15 cm long. Leaf-blades deciduous at the ligule; lanceolate; 5–10 cm long; 5–11 mm wide.

INFLORESCENCE Inflorescence composed of racemes.

Racemes 1; single; bilateral; 7–12 cm long; bearing few fertile spikelets; bearing 4–7 fertile spikelets on each. Spikelet packing broadside to rhachis.

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 6–8 fertile florets; with diminished florets at the apex. Spikelets lanceolate; laterally compressed; 45–60 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume lanceolate; 5–6 mm long; 0.66 length of upper glume; chartaceous; without keels. Lower glume apex acute. Upper glume lanceolate; 8–9 mm long; 0.9 length of adjacent fertile lemma; chartaceous; without keels. Upper glume apex acute.

FLORETS Fertile lemma elliptic; 9–11 mm long; chartaceous; without keel. Lemma apex acute; awned; 1 -awned. Principal lemma awn 1.5–3 mm long overall. Palea 1 length of lemma. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 3. Anthers 3. Stigmas 2. Ovary umbonate.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: western South America and Brazil.

NOTES Bambuseae. Gr Peru 1997.

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