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.

Ichnanthus mayarensis

HABIT Annual. Culms decumbent, or rambling; 10–40 cm long; rooting from lower nodes. Culm-internodes distally glabrous, or pilose (sparsely). Leaf-sheaths outer margin hairy. Ligule a ciliate membrane; 0.5 mm long. Leaf-blade base broadly rounded; asymmetrical; with a brief petiole-like connection to sheath; petiole 0.05 cm long. Leaf-blades lanceolate; 2–5 cm long; 3–9 mm wide; herbaceous. Leaf-blade venation with obscure cross veins. Leaf-blade surface glabrous, or puberulous. Leaf-blade apex acute.

INFLORESCENCE Inflorescence composed of racemes; terminal.

Racemes 4–5; borne along a central axis; erect; 0.5–1.5 cm long. Central inflorescence axis 1.5 cm long. Spikelet packing lax; irregular.

Spikelets ascending; in pairs. Fertile spikelets sessile; 2 in the cluster. Pedicels filiform; angular.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; acuminate; 3–3.5 mm long; falling entire; readily shedding fertile florets. Floret callus winged; with apical wings reduced to convex swellings.

GLUMES Glumes similar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 1.2–2 mm long; 0.5–0.66 length of spikelet; herbaceous; 1-keeled; 3–5 -veined. Lower glume lateral veins ribbed. Lower glume surface glabrous. Lower glume apex acute. Upper glume lanceolate; 1 length of spikelet; herbaceous; 1-keeled; 5 -veined. Upper glume lateral veins ribbed. Upper glume surface glabrous. Upper glume apex acuminate.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret similar to upper glume; oblong; 1 length of spikelet; 1-keeled; 5 -veined; ribbed; acuminate. Palea of lower sterile floret 0.3–0.5 length of lemma. Fertile lemma elliptic; dorsally compressed; 2–2.5 mm long; indurate; without keel. Lemma margins involute. Lemma apex obtuse. Palea involute; indurate.

FRUIT Caryopsis with adherent pericarp.

DISTRIBUTION South America: Caribbean and Brazil.

NOTES Paniceae. SAR 2003.

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