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.

Heteropogon

HABIT Annual (2), or perennial (3). Culms erect (3/3); robust (1/1); 30–97–250 cm long; with prop roots (1/1). Culm-nodes constricted (1/1). Lateral branches fastigiate (2/2). Ligule an eciliate membrane (3), or a fringe of hairs (2). Leaf-blades stiff (1), or firm (4). Leaf-blade midrib evident (1/1). Leaf-blade margins cartilaginous (1/1).

INFLORESCENCE Synflorescence simple (4), or compound (1); paniculate (1/1). Inflorescence composed of racemes; terminal (4), or terminal and axillary (1); subtended by an unspecialized leaf-sheath (4), or a spatheole (1); exserted (4), or enclosed (1). Spatheole linear (1/1); herbaceous (1/1).

Racemes single; erect (4), or ascending (1); unilateral (4/4); bearing 5–10 fertile spikelets on each (1/1). Rhachis fragile at the nodes. Rhachis internodes linear (4), or cuneate (1). Rhachis internode tip oblique.

Spikelets appressed; in pairs. Fertile spikelets sessile; 1 in the cluster (4), or 2 in the cluster (1). Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels oblong (4/4).

STERILE SPIKELETS Basal sterile spikelets well-developed.

Companion sterile spikelets well-developed; separately deciduous. Companion sterile spikelet callus linear. Companion sterile spikelet glumes muticous.

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear; subterete; 4.5–9.25–15 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus linear; bearded; base pungent; attached obliquely.

GLUMES Glumes exceeding apex of florets; firmer than fertile lemma. Lower glume linear (4), or elliptic (1), or oblong (1); coriaceous; without keels; 7–8 -veined (1/3), or 9 -veined (3/3). Lower glume surface convex (3), or grooved on either side of midvein (2); without pits; puberulous (2), or pubescent (4), or pilose (1), or hispidulous (1). Lower glume apex truncate (2), or obtuse (3). Upper glume linear; coriaceous; with undifferentiated margins (4), or membranous margins (1); without keels; wingless (4), or winged on margins (1); 3 -veined (1/1). Upper glume surface glabrous (4), or puberulous (1), or pubescent (1).

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret linear (2), or lanceolate (2), or elliptic (1); 1 length of fertile lemma; hyaline; 0 -veined (4), or 2 -veined (1). Fertile lemma linear, or oblong (1); membranous; wingless; 1 -veined (4), or 3 -veined (1). Lemma surface unwrinkled; without grooves. Lemma apex awned; 1 -awned. Principal lemma awn geniculate. Column of lemma awn pubescent (3), or hirtellous (2). Palea present (1), or absent or minute (4); 0.2–0.25–0.3 length of lemma.

FLOWER Anthers 3. Stigmas 2.

DISTRIBUTION Europe (1), or Africa (2), or Temperate Asia (3), or Tropical Asia, or Australasia (2), or Pacific (1), or North America (2), or South America (2).

Please cite this publication as detailed in How to Cite Version: 27th January 2014.