Arberella lancifolia

HABIT Perennial; caespitose. Culms erect, or geniculately ascending; 30–40 cm long; 3–4 -noded. Culm-internodes hollow. Culm-nodes brown. Lateral branches lacking. Leaves cauline; 4–8 per branch. Leaf-sheaths outer margin hairy. Ligule a ciliolate membrane; 0.5–0.7 mm long. Leaf-blade base with a brief petiole-like connection to sheath; petiole 0.2 cm long; petiole pilose. Leaf-blades linear, or lanceolate; 10–14.5 cm long; 8–13 mm wide. Leaf-blade surface pubescent; hairy on both sides. Leaf-blade apex acuminate.

INFLORESCENCE Monoecious; with male and female spikelets in the same inflorescence (or some all male). Inflorescence a panicle; comprising 1 fertile spikelets (and 8–10 male); terminal and axillary. Axillary inflorescences present in upper axils and in lower axils.

Panicle open; linear; 1.5–2 cm long; bearing few spikelets. Panicle branches pubescent.

Sexes segregated; on unisexual branches; with male below. Spikelets solitary. Fertile spikelets pedicelled. Male spikelets pedicelled; 2 in a cluster. Pedicels clavate (female), or linear (male); ciliate.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; 18–20 mm long; 2.1–2.9 mm wide; breaking up at maturity; disarticulating below each fertile floret. Floret callus evident; truncate.

GLUMES Glumes deciduous; similar; exceeding apex of florets; thinner than fertile lemma. Lower glume elliptic; 18–20 mm long; 1.1 length of upper glume; membranous; pallid; without keels; 9 -veined. Lower glume lateral veins with cross-veins. Lower glume surface scabrous; rough at apex. Lower glume apex acuminate. Upper glume elliptic; 16–18 mm long; 1.4–1.5 length of adjacent fertile lemma; membranous; pallid; without keels; 9–10 -veined. Upper glume lateral veins with cross-veins. Upper glume apex acuminate.

FLORETS Fertile florets female. Fertile lemma lanceolate; dorsally compressed; 10.8–12.6 mm long; 2.5 mm wide; indurate; pallid; shiny; without keel; 7 -veined. Lemma surface pubescent. Lemma margins pubescent. Lemma apex acuminate. Palea indurate; 8–9 -veined. Palea surface pubescent; hairy on back.

FLOWER Lodicules 3; 1 mm long; membranous. Anthers 3; 1.7 mm long. Stigmas 2.

MALE Male spikelets distinct from female; 1 flowered; lanceolate; 5–6.7 mm long. Male spikelet glumes absent. Male spikelet lemma 3 -veined.

DISTRIBUTION South America: Mesoamericana.

NOTES Olyreae. Soderstrom.

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