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.

Chaetium festucoides

HABIT Perennial; caespitose. Culms 30–120 cm long. Ligule a ciliate membrane. Leaf-blades flat; 10–27 cm long; 4–10 mm wide. Leaf-blade surface pilose. Leaf-blade apex acuminate.

INFLORESCENCE Inflorescence composed of racemes.

Racemes numerous; borne along a central axis; closely spaced; erect; unilateral; 1–4 cm long. Central inflorescence axis 6–15 cm long. Rhachis angular. Spikelet packing lax; irregular.

Spikelets in pairs. Fertile spikelets pedicelled; 2 in the cluster. Pedicels unequal.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets lanceolate; dorsally compressed; plano-convex; 4–5 mm long; falling entire. Spikelet callus linear; 0.7–0.8 mm long; pilose; hairy above; base obtuse; attached obliquely.

GLUMES Glumes dissimilar; shorter than spikelet; thinner than fertile lemma. Lower glume subulate; 10–20 mm long. Upper glume lanceolate; 0.75 length of spikelet; hyaline; without keels; 3 -veined. Upper glume lateral veins thickened; ribbed. Upper glume surface asperulous. Upper glume apex acuminate; awned; 1 -awned. Upper glume awn 15–20 mm long (flexuous).

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 1 length of spikelet; hyaline; 5 -veined; with thickened veins; ribbed; scaberulous; rough on veins; acute; awned. Awn of lower sterile floret flexuous; 4–11 mm long. Fertile lemma lanceolate; 4.5 mm long; coriaceous; without keel; 5 -veined. Lemma surface scaberulous; rough above. Lemma margins involute. Lemma apex acute; awned; 1 -awned. Principal lemma awn 0.5–2 mm long overall. Palea involute; 1 length of lemma; coriaceous.

DISTRIBUTION South America: northern South America and Brazil.

NOTES Paniceae. WDC.

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