Raddiella vanessiae

HABIT Annual; mat forming. Culms prostrate; 1–2 cm long. Culm-internodes purple; distally glabrous. Culm-nodes pubescent. Lateral branches ample. Leaves 3–5 per branch. Leaf-sheaths inflated; 0.18–0.32 cm long; striately veined; pubescent; with reflexed hairs. Ligule a fringe of hairs; 0.2–0.3 mm long. Leaf-blade base truncate; asymmetrical; with a brief petiole-like connection to sheath; petiole pubescent. Leaf-blades ovate; 0.27–0.33 cm long; 1.8–2.1 mm wide; membranous; mid-green and purple; discolorous with last colour beneath. Leaf-blade venation with 12–14 secondary veins. Leaf-blade surface puberulous; hairy adaxially. Leaf-blade margins scaberulous. Leaf-blade apex acute.

INFLORESCENCE Monoecious; with male and female spikelets in different inflorescences. Inflorescence comprising only a few spikelets; comprising 2–5 fertile spikelets; axillary; embraced at base by subtending leaf.

Spikelets solitary. Fertile spikelets pedicelled. Male spikelets pedicelled. Pedicels filiform; 0.3–1 mm long; glabrous; tip cupuliform.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 1–1.4 mm long; breaking up at maturity; disarticulating below each fertile floret. Spikelet callus square; incorporating lowest rhachilla internode with adnate lower glume; 0.2 mm long. Rhachilla internodes elongated between glumes.

GLUMES Glumes deciduous; similar; reaching apex of florets; thinner than fertile lemma; gaping. Lower glume linear, or ovate; 1–1.4 mm long; 1 length of upper glume; membranous; firmer on margins; without keels; 1–3 -veined. Lower glume lateral veins absent, or obscure. Lower glume surface pilose. Lower glume apex acute. Upper glume lanceolate, or ovate; 1–1.4 mm long; 1 length of adjacent fertile lemma; membranous; with cartilaginous margins; without keels; 1 -veined, or 3 -veined. Upper glume lateral veins absent, or obscure. Upper glume surface pilose. Upper glume apex acute.

FLORETS Fertile florets female. Fertile lemma lanceolate, or elliptic, or ovate; 0.9 mm long; cartilaginous; pallid; shiny; without keel; 3 -veined. Lemma surface smooth. Lemma margins involute; covering most of palea. Lemma apex acute. Palea 1 length of lemma; cartilaginous; 2-keeled.

FLOWER Anthers 3; 0.4–0.5 mm long; brown. Stigmas 2.

FRUIT Caryopsis with adherent pericarp; ellipsoid, or oblong; 0.65–0.95 mm long; dark brown. Hilum linear; 0.25 length of caryopsis.

MALE Male inflorescence terminal; unlike female; of few spikelets (1–2 spikelets). Male spikelets distinct from female; 1 flowered; separately deciduous; lanceolate; 1.1–1.2 mm long; glabrous. Male spikelet glumes absent. Male spikelet lemma 1.1–1.2 mm long; 3 -veined; muticous.

DISTRIBUTION South America: northern South America.

NOTES Olyreae. Judz. 2007.

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