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.

Rytidosperma

HABIT Perennial. Rhizomes absent (66), or short (8), or elongated (2). Stolons absent (71), or present (3). Culms erect (35/39), or geniculately ascending (10/39), or decumbent (4/39); robust (2/8), or slender (6/8); 2–35.49–140 cm long; without nodal roots (1/7), or rooting from lower nodes (7/7). Ligule a fringe of hairs. Leaf-blades persistent (60), or deciduous at the ligule (13); aciculate (5), or filiform (25), or linear (44); herbaceous (70), or coriaceous (3); stiff (12), or firm (60), or flaccid (1). Leaf-blade margins cartilaginous (1/1). Leaf-blade apex muticous (71), or pungent (3).

INFLORESCENCE Inflorescence a panicle (72), or composed of racemes (2), or comprising only a few spikelets (5); exserted (71), or embraced at base by subtending leaf (3).

Panicle open (27/66), or contracted (44/66), or spiciform (1/66). Primary panicle branches not whorled (71/72), or whorled at lower nodes (1/72).

Racemes single (2/2).

Spikelets solitary, or in pairs (1). Fertile spikelets pedicelled (72/72).

FERTILE SPIKELETS Spikelets comprising 2–5–10 fertile florets; with diminished florets at the apex. Spikelets lanceolate (3/69), or elliptic (4/69), or oblong (1/69), or obovate (1/69), or cuneate (60/69); laterally compressed; 3–10.76–25 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes definite. Floret callus brief (17), or evident (51), or elongated (5); glabrous (1/65), or pubescent (32/65), or pilose (29/65), or bearded (3/65); obtuse (70), or acute (1), or pungent (2).

GLUMES Glumes persistent; shorter than spikelet (17), or reaching apex of florets (13), or exceeding apex of florets (48); thinner than fertile lemma (65), or similar to fertile lemma in texture (8); incurved at apex (1), or parallel to lemmas (59), or gaping (13). Lower glume linear (2/69), or lanceolate (53/69), or elliptic (8/69), or oblong (3/69), or ovate (9/69); 0.9–0.9993–1.2 length of upper glume; hyaline (2/69), or membranous (61/69), or chartaceous (4/69), or scarious (2/69); without keels (66/69), or 1-keeled (3/69); 1–6–13 -veined. Lower glume surface smooth (68), or asperulous (7); without pits; glabrous (71), or puberulous (2), or pilose (1). Lower glume apex entire (72), or erose (1); truncate (1/69), or obtuse (11/69), or acute (39/69), or acuminate (20/69), or attenuate (4/69), or setaceously attenuate (1/69); muticous (68/69), or mucronate (1/69). Upper glume linear (2/69), or lanceolate (53/69), or elliptic (8/69), or oblong (4/69), or ovate (8/69); 0.7–1.522–3 length of adjacent fertile lemma; hyaline (2/69), or membranous (60/69), or chartaceous (5/69), or scarious (2/69); with undifferentiated margins (57), or hyaline margins (11), or membranous margins (2), or scarious margins (3); without keels (66/69), or 1-keeled (3/69); 1–5–13 -veined. Upper glume primary vein eciliate (72), or ciliate (1), or pubescent (1). Upper glume lateral veins with cross-veins (1/1); meeting at apex (2/2). Upper glume surface smooth (68), or asperulous (7); glabrous (71), or puberulous (2), or pilose (1). Upper glume apex truncate (1/69), or obtuse (11/69), or acute (38/69), or acuminate (21/69), or attenuate (4/69), or setaceously attenuate (1/69); muticous (68/69), or mucronate (1/69).

FLORETS Fertile lemma linear (1/69), or lanceolate (7/69), or elliptic (6/69), or oblong (48/69), or ovate (7/69), or oblanceolate (1/69); membranous (4/69), or chartaceous (63/69), or coriaceous (2/69); without keel (69/69); wingless; 3 -veined (1/62), or 5 -veined (4/62), or 6 -veined (3/62), or 7 -veined (15/62), or 8 -veined (5/62), or 9 -veined (49/62), or 11 -veined (1/62). Lemma lateral veins obscure (2/2). Lemma surface unwrinkled; without grooves; glabrous (54), or pubescent (9), or pilose (9), or villous (2); without hair tufts (4), or with basal hair tufts near margin (2), or with marginal hair tufts (24), or with a transverse row of hair tufts (13), or with 2 transverse rows of hair tufts (34), or with a transverse fringe of hair (5). Lemma margins eciliate (66), or ciliolate (1), or ciliate (6), or pubescent (1). Lemma apex entire (1), or dentate (9), or lobed (63); 2 -fid (72/72); incised 0.05–0.5085–0.8 of lemma length; obtuse (2/22), or acute (5/22), or acuminate (5/22), or attenuate (6/22), or setaceously attenuate (9/22); muticous (2), or mucronate (5), or awned (70); 1 -awned (23/70), or 3 -awned (53/70). Principal lemma awn from a sinus; straight (15), or curved (3), or flexuous (1), or geniculate (57). Lateral lemma awns shorter than principal (3/3). Palea 0.75–0.875–1 length of lemma; membranous (72), or chartaceous (1); 2 -veined (1/1). Palea keels smooth (71), or scabrous (1), or spinulose (1); eciliate (18), or ciliolate (51), or ciliate (4). Palea surface glabrous (45), or pubescent (7), or pilose (25), or villous (4). Palea apex dentate (9/9). Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2 (68/68); fleshy (68/68); glabrous (14/68), or ciliate (55/68). Anthers 3 (68/68).

FRUIT Caryopsis with adherent pericarp; ellipsoid (3/34), or oblong (5/34), or ovoid (2/34), or obovoid (21/34), or oblanceolate (4/34); dorsally compressed (1/1); biconvex (1/2), or plano-convex (1/2). Embryo 0.33–0.5483–1 length of caryopsis. Hilum punctiform (2/7), or elliptic (5/7).

DISTRIBUTION Africa (1), or Tropical Asia (12), or Australasia (56), or Pacific (3), or South America (6).

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