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.

Hilaria semplei

HABIT Perennial. Stolons present. Culms erect; 20–35 cm long. Culm-nodes bearded. Leaf-sheaths striately veined; pilose; with tubercle-based hairs. Ligule an eciliate membrane; 0.5–1 mm long. Leaf-blades 2.5–15 cm long; 1–2.5 mm wide. Leaf-blade surface pilose; hairy on both sides; with tubercle-based hairs. Leaf-blade margins scabrous.

INFLORESCENCE Inflorescence composed of racemes.

Racemes borne along a central axis; closely spaced; in a multilateral false spike; cuneate; unilateral; 0.8–1 cm long; bearing a triad of spikelets. Central inflorescence axis 2–4 cm long. Rhachis obsolete; deciduous from axis.

Spikelets in threes. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets sessile; 2 in the cluster.

STERILE SPIKELETS Companion sterile spikelets well-developed; male; cuneate; asymmetrical; dorsally compressed; 4.5–6 mm long; as long as fertile; deciduous with the fertile. Companion sterile spikelet glumes united below; coriaceous; 7 -veined; pilose; lobed; 2 -fid; muticous. Companion sterile spikelet lemmas 2; exserted from glumes; muticous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets oblong; laterally compressed; 8–10 mm long; falling entire; deciduous with accessory branch structures.

GLUMES Glumes connate along margins below; shorter than spikelet; firmer than fertile lemma. Lower glume oblong; 4–5 mm long; coriaceous; pallid; 1-keeled; 7 -veined. Lower glume apex lobed; 2 -fid; awned; 1 -awned. Lower glume awn 6–7 mm long. Upper glume oblong; 6–7 mm long; coriaceous; pallid; 1-keeled; 7 -veined. Upper glume apex lobed; 2 -fid; awned; 1 -awned. Upper glume awn 6–7 mm long.

FLORETS Fertile florets female. Fertile lemma ovate; laterally compressed; 8–10 mm long; cartilaginous; keeled; 3 -veined. Lemma apex caudate.

FLOWER Anthers 3.

DISTRIBUTION North America: Mexico.

NOTES Cynodonteae. Swallen.

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