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.

Ectrosia

HABIT Annual (12), or perennial (2). Culms erect (11/11), or geniculately ascending (10/11); slender (8/8); 6–32.67–80 cm long. Lateral branches lacking (6/9), or sparse (2/9), or ample (2/9). Ligule a fringe of hairs. Leaf-blades filiform (1), or linear (13); stiff (5), or firm (9).

INFLORESCENCE Inflorescence a panicle; exserted (13), or embraced at base by subtending leaf (1).

Panicle open (7), or contracted (8), or spiciform (1).

Spikelets appressed (1/3), or spreading (2/3); solitary. Fertile spikelets pedicelled. Pedicels linear (12/12).

FERTILE SPIKELETS Spikelets comprising 1 fertile florets (5), or 2–3 fertile florets (9), or 4 fertile florets (6), or 5–6 fertile florets (3), or 7–8 fertile florets (2), or 9 fertile florets (1), or 10–13 fertile florets (2), or 14–25 fertile florets (1); with diminished florets at the apex. Spikelets linear (7), or lanceolate (2), or oblong (6), or ovate (2), or obovate (1); laterally compressed; 2–9.017–30 mm long; breaking up at maturity; rhachilla deciduous (13), or rhachilla persistent (1); disarticulating below each fertile floret (1/13), or above glumes but not between florets (13/13); retaining paleas (1/1). Rhachilla internodes definite (13/13); glabrous (12/13), or pubescent (1/13). Floret callus pubescent (1/1); obtuse (13), or acute (1).

GLUMES Glumes deciduous; shorter than spikelet. Lower glume lanceolate (13), or ovate (1); 0.5–0.78–1 length of upper glume; membranous; 1-keeled; 1 -veined (12/13), or 2 -veined (1/13), or 3 -veined (2/13). Lower glume lateral veins absent (12), or obscure (1), or distinct (2). Lower glume surface without pits. Lower glume apex obtuse (3/13), or acute (10/13), or acuminate (4/13). Upper glume lanceolate (13), or ovate (1); 0.4–0.7032–1.1 length of adjacent fertile lemma; membranous; 1-keeled; 1 -veined (10/13), or 2 -veined (6/13), or 3 -veined (9/13). Upper glume apex obtuse (3/12), or acute (9/12), or acuminate (3/12), or cuspidate (1/12).

FLORETS Fertile lemma lanceolate (7), or elliptic (2), or oblong (4), or ovate (4); lanceolate in profile (2/2); membranous (6), or cartilaginous (1), or coriaceous (7); keeled; wingless (13), or winged on keel (1); 3 -veined (12), or 4 -veined (2), or 5 -veined (4), or 6–7 -veined (3). Lemma midvein without distinctive roughness (3), or scaberulous (10), or scabrous (1); eciliate (13), or ciliate (1). Lemma lateral veins prominent (2/2); without ribs (13), or ribbed (1). Lemma surface smooth (7), or asperulous (6), or scaberulous (2), or scabrous (1); unwrinkled; without grooves; glabrous (13), or pubescent (1). Lemma margins eciliate (13), or ciliate (1). Lemma apex emarginate (2), or acute (4), or acuminate (12), or setaceously attenuate (2); muticous (3), or mucronate (3), or awned (12); 1 -awned (12/12). Palea 0.4–0.548–0.66 length of lemma; 2 -veined. Palea keels wingless (9), or winged (5); smooth (10), or scaberulous (2), or scabrous (2); eciliate (3), or ciliolate (11). Apical sterile florets resembling fertile though underdeveloped (2), or distinct from fertile (12); 2 in number (1/12), or 3 in number (5/12), or 4 in number (10/12), or 5 in number (8/12), or 6 in number (2/12), or 7–8 in number (1/12); barren (12/12); rudimentary (10/12), or linear (1/12), or lanceolate (2/12). Apical sterile lemmas muticous (1/12), or awned (11/12).

FLOWER Lodicules 2 (2/2); fleshy (2/2). Anthers 3 (13/13).

FRUIT Caryopsis with adherent pericarp; lanceolate (1/7), or ellipsoid (2/7), or oblong (2/7), or ovoid (2/7); isodiametric (1/1). Embryo 0.5 length of caryopsis.

DISTRIBUTION Tropical Asia (3), or Australasia, or Pacific (2).

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