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.

Raddiella

HABIT Annual (7), or perennial (1). Culms decumbent (2), or prostrate (2), or rambling (4); slender (1/3), or weak (2/3); 1–10.31–30 cm long; rooting from lower nodes (4/4). Culm-nodes swollen (2/2). Lateral branches ample (1/1). Ligule an eciliate membrane (5), or a ciliolate membrane (1), or a fringe of hairs (1), or absent (1). Leaf-blade base with a brief petiole-like connection to sheath. Leaf-blades lanceolate (3), or elliptic (2), or ovate (4); membranous (7), or coriaceous (1).

INFLORESCENCE Monoecious; with male and female spikelets in the same inflorescence (3), or with male and female spikelets in different inflorescences (5). Inflorescence a panicle (1), or comprising only a few spikelets; terminal and axillary (1), or axillary (7); exserted (3), or embraced at base by subtending leaf (7).

Sexes segregated (3/3); with male above (1/3), or below (2/3). Spikelets solitary. Fertile spikelets pedicelled. Male spikelets pedicelled; 1–11 in a cluster (1/1). Pedicels filiform (1/2), or oblong (1/2); tip cupuliform (2/2).

FERTILE SPIKELETS Spikelets comprising 1 fertile florets; without rhachilla extension. Spikelets elliptic (6), or ovate (2), or obovate (1); dorsally compressed; 0.83–1.53–2.4 mm long; falling entire (5), or breaking up at maturity (3); disarticulating below each fertile floret (3/3). Spikelet callus square; incorporating lowest rhachilla internode with adnate lower glume. Rhachilla internodes elongated between glumes.

GLUMES Glumes persistent (2/3), or deciduous (1/3); reaching apex of florets; thinner than fertile lemma; parallel to lemmas (7), or gaping (1). Lower glume linear (1), or elliptic (6), or ovate; 0.9–0.9875–1 length of upper glume; membranous (7), or herbaceous (1); without keels; 1–2 -veined (1), or 3 -veined, or 4–5 -veined (1). Lower glume lateral veins absent (1), or obscure (1), or distinct (7). Lower glume surface without pits; glabrous (2), or pubescent (3), or pilose (5). Lower glume apex acute (3), or acuminate (6). Upper glume lanceolate (1), or elliptic (6), or ovate; 1 length of adjacent fertile lemma; membranous (7), or herbaceous (1); with undifferentiated margins (7), or cartilaginous margins (1); without keels; 1 -veined (1), or 3 -veined, or 4–5 -veined (3). Upper glume surface glabrous (2), or pubescent (3), or pilose (5). Upper glume apex acute (3), or acuminate (6).

FLORETS Fertile florets female. Fertile lemma lanceolate (1), or elliptic (4), or ovate (4), or obovate (1); not gibbous (7), or lunate in profile (1); cartilaginous (1), or indurate (7); without keel; wingless; 3 -veined (4/4), or 4–5 -veined (1/4). Lemma surface smooth (4), or papillose (4); unwrinkled; without grooves. Lemma margins involute; exposing palea (7), or covering most of palea (1). Lemma apex obtuse (1), or acute (6), or rostrate (1). Palea 1 length of lemma; cartilaginous (1), or indurate (7).

FLOWER Anthers 3 (7/7). Stigmas 2 (1/1).

FRUIT Caryopsis with adherent pericarp (7/7); ellipsoid (3/6), or oblong (1/6), or ovoid (2/6), or orbicular (1/6), or obovoid (1/6). Embryo 0.2–0.3167–0.5 length of caryopsis. Hilum punctiform (3/6), or elliptic (2/6), or linear (1/6); 0.25 length of caryopsis.

MALE Male inflorescence terminal (5/5); unlike female (5/5); a panicle (1/5), or of few spikelets (4/5). Male spikelets distinct from female; lanceolate (6), or elliptic (2). Male spikelet glumes absent, or 2 (1). Male spikelet lemma muticous.

DISTRIBUTION South America.

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