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.

Distichlis

HABIT Perennial. Rhizomes absent (2), or elongated (5). Culms erect (3/3), or geniculately ascending (1/3); 2–21.35–60 cm long; firm (6), or wiry (1). Ligule a ciliolate membrane (6), or a fringe of hairs (1). Leaf-blades aciculate (1), or linear (6); herbaceous (3), or coriaceous (4); stiff (5), or firm (2). Leaf-blade apex muticous (1), or pungent (6).

INFLORESCENCE Dioecious. Inflorescence a panicle (1), or composed of racemes (5), or comprising only a few spikelets (2); exserted, or embraced at base by subtending leaf (1), or enclosed (1).

Panicle contracted (1/1).

Racemes single (2/5), or borne along a central axis (3/5); not compacted (1/3), or in a head (2/3); appressed (1/5), or ascending (4/5); paucilateral (5/5); bearing few fertile spikelets (5/5); bearing 1 fertile spikelets on each (1/2), or 2–3 fertile spikelets on each (2/2). Rhachis angular (1/1).

Spikelets solitary. Fertile spikelets pedicelled. Pedicels linear.

FERTILE SPIKELETS Spikelets comprising 1–2 fertile florets (1), or 5–6 fertile florets (4), or 7 fertile florets (5), or 8–9 fertile florets (4), or 10–14 fertile florets (2), or 15 fertile florets (1); with diminished florets at the apex. Spikelets lanceolate (1), or elliptic (1), or oblong (2), or ovate (3); laterally compressed; 4.15–13.22–30 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes definite.

GLUMES Glumes persistent; shorter than spikelet; thinner than fertile lemma. Lower glume lanceolate (4), or ovate (3); 0.6–0.8321–1 length of upper glume; scarious; 1-keeled; 1–2 -veined (1), or 3 -veined (6), or 4 -veined (4), or 5 -veined (5), or 6–9 -veined (1). Lower glume lateral veins absent (1), or distinct. Lower glume surface without pits. Lower glume apex obtuse (1), or acute (6). Upper glume ovate; 0.6–0.8857–1 length of adjacent fertile lemma; scarious; 1-keeled; 3 -veined (3), or 4 -veined (2), or 5 -veined (5), or 6 -veined (3), or 7 -veined (4), or 8–9 -veined (2). Upper glume apex obtuse (1), or acute (6).

FLORETS Fertile florets female. Fertile lemma ovate; coriaceous; keeled; wingless; 5–6 -veined (3), or 7–8 -veined (4), or 9 -veined (5), or 10 -veined (3), or 11 -veined (4), or 12 -veined (1). Lemma lateral veins prominent (1/1). Lemma surface unwrinkled; without grooves. Lemma apex obtuse (1), or acute (5), or acuminate (1). Palea 0.9 length of lemma; coriaceous; 2 -veined. Palea keels wingless (1), or winged (6); smooth (5), or scaberulous (2). Apical sterile florets resembling fertile though underdeveloped.

FLOWER Anthers 3.

MALE Male inflorescence similar to female; of racemes along a central axis (3/3). Male spikelets similar to female but less developed; elliptic (1/3), or oblong (1/3), or ovate (1/3). Male spikelet glumes 2 (6/6). Male spikelet lemma muticous (6/6).

DISTRIBUTION Australasia (1), or Pacific (1), or North America (2), or South America (5).

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