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.

Pereilema crinitum

HABIT Annual; caespitose. Culms decumbent; 15–80 cm long; rooting from lower nodes. Leaf-sheath oral hairs ciliate. Leaf-sheath auricles falcate. Ligule an eciliate membrane; 0.3–0.5 mm long. Leaf-blades 5–15 cm long; 2–3 mm wide.

INFLORESCENCE Inflorescence a panicle.

Panicle spiciform; linear; continuous, or interrupted; 5–13 cm long; 2–3 cm wide. Primary panicle branches appressed; 1 cm long.

Spikelets subtended by an involucre. Fertile spikelets pedicelled; 1–2 in the cluster. Companion sterile spikelets sessile; 2–3 in the cluster. Involucre composed of imperfect spikelets; cuneate; 3 mm long. Pedicels oblong.

STERILE SPIKELETS Companion sterile spikelets represented by awns; comprising a tuft of awns; 3 mm long; persistent. Companion sterile spikelet glumes glabrous.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets lanceolate; laterally compressed; 1.5 mm long; breaking up at maturity; disarticulating below each fertile floret. Floret callus bearded. Floret callus hairs 0.33–0.5 length of lemma.

GLUMES Glumes persistent; similar; shorter than spikelet; thinner than fertile lemma. Lower glume oblong; 1 mm long; 1 length of upper glume; membranous; 1-keeled; 1 -veined. Lower glume lateral veins absent. Lower glume apex emarginate; awned; 1 -awned. Lower glume awn 2 mm long. Upper glume oblong; 1 mm long; 0.66 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined. Upper glume lateral veins absent. Upper glume apex emarginate; awned; 1 -awned. Upper glume awn 2 mm long.

FLORETS Fertile lemma ovate; 1.5 mm long; cartilaginous; keeled; 3 -veined. Lemma lateral veins close to margins. Lemma surface scabrous. Lemma apex acuminate; awned; 1 -awned. Principal lemma awn flexuous; 20–30 mm long overall. Palea 1 length of lemma.

FLOWER Anthers 3; 0.5–0.7 mm long; yellow.

FRUIT Caryopsis with adherent pericarp.

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

NOTES Eragrostideae. Pohl.

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