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.

Acroceras attenuatum

HABIT Annual. Culms prostrate; 20–40 cm long; rooting from lower nodes. Ligule an eciliate membrane. Leaf-blades linear, or lanceolate; tapering towards sheath; 5–18 cm long; 5–20 mm wide. Leaf-blade venation with obscure cross veins. Leaf-blade surface glabrous, or pubescent. Leaf-blade apex acuminate; filiform.

INFLORESCENCE Inflorescence a panicle.

Panicle open; elliptic, or oblong; 6–12 cm long; contracted about primary branches. Primary panicle branches appressed, or ascending; 2–6 cm long; bearing spikelets almost to the base. Panicle branches angular.

Spikelets solitary, or in pairs. Fertile spikelets pedicelled; 1 in the cluster, or 2 in the cluster. Pedicels fused to each other; united below; linear; angular; unequal; 1–10 mm long.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets elliptic; dorsally compressed; 3–3.5(–4) mm long; falling entire. Spikelet callus glabrous; base truncate. Rhachilla internodes elongated between glumes.

GLUMES Glumes dissimilar; reaching apex of florets; thinner than fertile lemma. Lower glume ovate; 0.75 length of spikelet; herbaceous; black; without keels; 3 -veined. Lower glume apex acute. Upper glume elliptic; 2.5–3.5 mm long; herbaceous; black; 3 -veined. Upper glume apex obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret similar to upper glume; elliptic; 1 length of fertile lemma; 1 length of spikelet; herbaceous; 3 -veined; obtuse. Fertile lemma elliptic; dorsally compressed; 2.5–3.5 mm long; indurate; pallid; shiny. Lemma margins involute. Lemma apex acute; with a little green crest, or with a green spot. Palea reflexed at apex; elliptic; involute; 1 length of lemma; indurate; 2 -veined; without keels.

FRUIT Disseminule comprising a spikelet.

DISTRIBUTION Africa: east tropical and southern tropical.

NOTES Paniceae. FTEA.

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