GrassBase - The Online World Grass Flora

Descriptions

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

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

Coelorachis aurita

HABIT Perennial; caespitose. Basal innovations flabellate. Culms erect; 100–250 cm long; 3–7 mm diam. Culm-internodes elliptical in section; solid. Culm-nodes brown. Lateral branches ample; arising from mid culm and upper culm. Leaf-sheaths keeled. Ligule a ciliolate membrane; 0.6–0.7 mm long. Leaf-blades conduplicate; 15–60 cm long; 4–10 mm wide.

INFLORESCENCE Synflorescence compound; fastigiate. Inflorescence composed of racemes; terminal and axillary; subtended by a spatheole; embraced at base by subtending leaf. Spatheole linear.

Racemes 1; single; 4–9 cm long; 1.5–2 mm wide. Rhachis fragile at the nodes; angular. Rhachis internodes oblong; 2–2.7 mm long. Rhachis internode tip transverse; crateriform.

Spikelets appressed; in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels oblong; 2.5–3 mm long; tip cupuliform; auriculate.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; oblong; dorsally compressed; 2.3–4.3 mm long; shorter than fertile; separately deciduous. Companion sterile spikelet glumes winged on keels. Companion sterile spikelet lemmas 2; enclosed by glumes.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets oblong; dorsally compressed; 4–4.7 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus base truncate; with central peg; attached transversely.

GLUMES Glumes dissimilar; exceeding apex of florets; firmer than fertile lemma. Lower glume oblong; 1 length of spikelet; coriaceous; 2-keeled; winged on keel; winged broadly; winged above. Lower glume surface flat; areolate. Lower glume apex emarginate. Upper glume oblong; chartaceous; 1-keeled; 3 -veined. Upper glume apex acute.

FLORETS Basal sterile florets barren; with palea. Lemma of lower sterile floret oblong; 2.5–3.1 mm long; hyaline; obtuse. Fertile lemma elliptic; 2.3–2.8 mm long; hyaline; without keel; 0–1 -veined. Lemma apex obtuse. Palea hyaline.

FLOWER Anthers 3; 0.8–1.5 mm long; purple.

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

NOTES Andropogoneae. Fl Costa Rica.

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