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.

Hyparrhenia

HABIT Annual (16), or perennial (40). Rhizomes absent (42), or short (12), or elongated (2). Culms erect (49/55), or geniculately ascending (7/55), or decumbent (6/55), or rambling (2/55); robust (15/25), or slender (10/25); 5–144.2–400 cm long; firm (51), or wiry (5); without nodal roots (5/13), or with prop roots (13/13). Lateral branches fastigiate (1/1). Leaf-sheath auricles absent (52), or erect (6). Ligule an eciliate membrane (54), or a ciliolate membrane (2). Leaf-blade base without a false petiole (55), or with a false petiole (3). Leaf-blades filiform (2), or linear, or lanceolate (1); stiff (12), or firm (43), or flaccid (3). Leaf-blade midrib conspicuous (1/1).

INFLORESCENCE Synflorescence simple (1), or compound (55); scanty (11/55), or linear (2/55), or paniculate (40/55), or fastigiate (1/55), or fasciculate (2/55), or globose (1/55). Inflorescence composed of racemes; terminal (1), or terminal and axillary (55); subtended by a spatheole; exserted (22), or embraced at base by subtending leaf (21), or enclosed (22). Spatheole linear (26), or lanceolate (37), or ovate (2); membranous (48), or chartaceous (1), or herbaceous (1), or scarious (7).

Racemes paired; side by side, or end to end (1); appressed (2), or erect (18), or ascending (2), or spreading (3), or deflexed (34); unilateral (1/1); bearing few fertile spikelets (49), or many spikelets (9); bearing 1–3–13 fertile spikelets on each. Rhachis fragile at the nodes. Spikelet packing contiguous (55), or lax (1). Rhachis internodes linear. Rhachis internode tip oblique; flat. Raceme-bases filiform (22), or linear (4), or flattened (33); subequal (29), or unequal (the longer measured) (28); unappendaged (40), or scariously rimmed (6), or shortly lobed (6), or extended into an oblong appendage (9).

Spikelets appressed (55/55); in pairs. Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster. Pedicels linear; tip oblique.

STERILE SPIKELETS Basal sterile spikelets well-developed; not involucral (50), or forming an involucre about the fertile (6).

Companion sterile spikelets well-developed; separately deciduous. Companion sterile spikelet callus indistinct (52), or square (4), or oblong (1). Companion sterile spikelet glumes muticous (30/55), or mucronate (15/55), or awned (34/55).

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear (10), or lanceolate (43), or elliptic (2), or oblong (13), or ovate (1), or oblanceolate (1); dorsally compressed; 3.32–6.342–20 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus brief (2), or square (4), or oblong (7), or cuneate (35), or linear (15); pubescent (53), or pilose (3); base truncate (1), or obtuse (16), or acute (23), or pungent (21); attached obliquely.

GLUMES Glumes exceeding apex of florets; firmer than fertile lemma. Lower glume lanceolate; chartaceous (1), or coriaceous; without keels; 5 -veined (1/7), or 9 -veined (5/7), or 10 -veined (1/7), or 11 -veined (2/7). Lower glume lateral veins without ribs (53), or ribbed (5). Lower glume surface convex (51), or flat (3), or concave (6), or grooved on either side of midvein (2); smooth (54), or asperulous (1), or scabrous (1), or spinose (1); without pits; glabrous (29), or puberulous (6), or pubescent (23), or pilose (10), or hirsute (6), or villous (19), or hispidulous (8). Lower glume apex entire (5), or dentate (51); 2 -fid (51/51); truncate (1/1). Upper glume linear (55), or lanceolate (1); 1.1 length of adjacent fertile lemma; chartaceous (1), or coriaceous; without keels; 3 -veined (2/2). Upper glume surface glabrous (54), or pubescent (1), or hirsute (1). Upper glume apex entire (55), or dentate (1); 2 -fid (1/1); acute (2/2); muticous (54), or mucronate (2).

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 1 length of fertile lemma; hyaline; 0 -veined (1/54), or 2 -veined (53/54); truncate (1/1). Fertile lemma linear (55), or ovate (1); membranous; without keel; wingless; 1 -veined (54/54). Lemma surface unwrinkled; without grooves. Lemma margins eciliate (54), or ciliolate (1), or ciliate (1). Lemma apex entire (2), or dentate (54); 2 -fid (54/54); emarginate (1/2), or truncate (1/2); mucronate (2), or awned (55); 1 -awned (55/55). Principal lemma awn apical (1), or from a sinus (55); straight (1), or geniculate (55); limb glabrous (55), or puberulous (1). Column of lemma awn glabrous (1/55), or hispidulous (1/55), or puberulous (16/55), or pubescent (34/55), or ciliate (1/55), or hirtellous (9/55), or hirsute (3/55). Palea present (2), or absent or minute (54).

FLOWER Lodicules 2 (53/53); fleshy (53/53). Anthers 3 (54/54). Stigmas 2 (54/54).

FRUIT Caryopsis with adherent pericarp (1/1); ellipsoid (1/2), or oblong (1/2); dorsally compressed (1/1).

DISTRIBUTION Europe (1), or Africa (55), or Temperate Asia (12), or Tropical Asia (11), or Australasia (3), or Pacific (3), or North America (5), or South America (3).

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