GrassBase - The Online World Grass Flora


W.D. Clayton, M. Vorontsova, K.T. Harman & H. Williamson

© Copyright The Board of Trustees, Royal Botanic Gardens, Kew.

Echinolaena gracilis

HABIT Perennial; mat forming. Rhizomes elongated. Culms rambling; 20–50 cm long; rooting from lower nodes. Culm-internodes distally pilose. Culm-nodes bearded. Leaf-sheaths 1.5–2 cm long; hispid; with tubercle-based hairs. Ligule a fringe of hairs; 0.5 mm long. Leaf-blade base cordate. Leaf-blades linear, or lanceolate; 2–4 cm long; 5–6 mm wide. Leaf-blade venation without cross veins. Leaf-blade surface pilose; hairy adaxially; with tubercle-based hairs. Leaf-blade margins cartilaginous; tuberculate-ciliate.

INFLORESCENCE Inflorescence composed of racemes; embraced at base by subtending leaf. Peduncle tipped by a glumaceous appendage.

Racemes 1; single; spreading; unilateral; 2–2.5 cm long. Rhachis flattened.

Spikelets ascending; solitary, or in pairs. Fertile spikelets sessile; 1–2 in the cluster; subequal, or the lower smaller (and often aborted).

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; acuminate; 7–10.5 mm long; falling entire; readily shedding fertile florets. Floret callus winged; with apical wings adnate to lemma; these appendages 1.5–2 mm long (slender).

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume lanceolate; 7–10.5 mm long; 1 length of spikelet; coriaceous; without keels; 7 -veined. Lower glume lateral veins ribbed. Lower glume surface pilose; with tubercle-based hairs. Lower glume apex caudate. Upper glume ovate; 6–6.5 mm long; 0.6–0.8 length of spikelet; herbaceous; without keels; 9 -veined. Upper glume lateral veins ribbed. Upper glume surface pilose; hairy above; with tubercle-based hairs. Upper glume apex acuminate.

FLORETS Basal sterile florets male; with palea. Lemma of lower sterile floret ovate; 1 length of spikelet; herbaceous; 5 -veined; hispid; hairy above; acute. Fertile lemma elliptic; dorsally compressed; 3.6–3.7 mm long; indurate; shiny; without keel; 5 -veined. Lemma margins involute. Lemma apex obtuse. Palea indurate.

DISTRIBUTION North America: Mexico. South America: Mesoamericana, northern South America, and western South America.

NOTES Paniceae. SAR 2003.

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