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.

Rhipidocladum

HABIT Perennial. Rhizomes absent (1), or short (15); pachymorph (15/15). Culms erect (1/13), or geniculately ascending (2/13), or rambling (1/13), or arching (9/13), or leaning (3/13), or scandent (2/13); 200–983.1–3000 cm long; woody. Culm-internodes terete. Lateral branches dendroid. Branch complement many (15/15); in a clump (1/15), or flabellate (14/15); at the node (15), or subtended by a bare patch above the node (1); with subequal branches (6/6); thinner than stem (5/5). Culm-sheaths deciduous (3/3). Culm-sheath blade linear (1/6), or lanceolate (1/6), or triangular (4/6); as wide as sheath at base (1/1). Leaf-sheath auricles absent (10), or erect (6). Ligule an eciliate membrane (9), or a ciliolate membrane (6), or absent (1). Leaf-blade base with a brief petiole-like connection to sheath. Leaf-blades persistent (11), or deciduous at the ligule (5); linear (8), or lanceolate (9), or ovate (1). Leaf-blade midrib indistinct (4/4). Leaf-blade venation without cross veins, or with obscure cross veins (1).

INFLORESCENCE Inflorescence composed of racemes; terminal (14), or terminal and axillary (2).

Racemes single; unilateral (11/15), or bilateral (2/15), or paucilateral (2/15); bearing few fertile spikelets (4), or many spikelets (12); bearing 2 fertile spikelets on each (3/12), or 3–6 fertile spikelets on each (4/12), or 7–8 fertile spikelets on each (5/12), or 9–10 fertile spikelets on each (4/12), or 11–18 fertile spikelets on each (1/12), or 22–25 fertile spikelets on each (1/12). Rhachis flattened (1/1). Spikelet packing broadside to rhachis (1/1); crowded (1), or contiguous (11), or lax (1), or distant (3); 2 -rowed (3/3).

Spikelets appressed (2/3), or spreading (1/3); solitary. Fertile spikelets sessile (14), or pedicelled (2).

FERTILE SPIKELETS Spikelets comprising 0 basal sterile florets (1/14), or 1 basal sterile florets (13/14), or 2 basal sterile florets (2/14); 1 fertile florets (1), or 2–3 fertile florets (11), or 4 fertile florets (6), or 5 fertile florets (2), or 6 fertile florets (1); with diminished florets at the apex. Spikelets linear (5), or lanceolate (3), or oblong (1), or oblanceolate (9); laterally compressed (13), or subterete (3); 8–21.23–60 mm long; breaking up at maturity; disarticulating below each fertile floret. Rhachilla internodes brief up to lowest fertile floret (8), or elongated between glumes (1), or elongated below basal sterile floret (1), or elongated below proximal fertile floret (6); definite; glabrous (14), or pubescent (1), or pilose (1). Floret callus glabrous (1/1).

GLUMES Glumes one the lower absent or obscure (1), or two, or several (1); persistent; shorter than spikelet; thinner than fertile lemma (15), or similar to fertile lemma in texture (1). Lower glume subulate (6), or linear (3), or lanceolate (5), or elliptic (1), or ovate (1); 0.2–0.49–0.7 length of upper glume; chartaceous (2/2); without keels (1/1); 1 -veined (4/8), or 3 -veined (3/8), or 4 -veined (2/8), or 5 -veined (1/8). Lower glume lateral veins absent (4), or distinct (11), or prominent (1). Lower glume surface smooth (15), or scabrous (1); without pits; glabrous (15), or puberulous (1), or pubescent (2). Lower glume apex acute (8/9), or acuminate (1/9); muticous (5/10), or mucronate (1/10), or awned (4/10). Upper glume linear (1), or lanceolate (7), or ovate (9); 0.15–0.5312–0.9 length of adjacent fertile lemma; chartaceous (15/15); without keels (15), or 1-keeled (1); 5 -veined (7/10), or 6 -veined (2/10), or 7 -veined (5/10). Upper glume surface smooth (15), or scabrous (1); glabrous (15), or puberulous (1), or pubescent (2). Upper glume apex obtuse (1/15), or acute (6/15), or acuminate (7/15), or setaceously attenuate (2/15); muticous (7), or awned (9); 1 -awned (9/9).

FLORETS Basal sterile florets barren (14/14); with palea (1/14), or without significant palea (14/14). Lemma of lower sterile floret lanceolate (3/11), or ovate (8/11); 0.6–0.85–1 length of fertile lemma; chartaceous (11/11); 4 -veined (1/7), or 5 -veined (3/7), or 6 -veined (2/7), or 7 -veined (5/7), or 8 -veined (2/7), or 9 -veined (3/7), or 10–11 -veined (1/7); obtuse (1/11), or acute (5/11), or acuminate (6/11); muticous (5/11), or mucronate (1/11), or awned (8/11). Fertile lemma lanceolate (6), or ovate (10); chartaceous (1), or coriaceous (15); without keel; wingless; 5–6 -veined (6), or 7 -veined (12), or 8 -veined (6), or 9 -veined (8), or 10–11 -veined (1), or 13–14 -veined (1), or 15 -veined (2), or 16–19 -veined (1). Lemma midvein eciliate (15), or ciliolate (1). Lemma surface smooth (12), or scaberulous (3), or scabrous (1); unwrinkled; without grooves; glabrous (14), or pubescent (1), or hispidulous (1). Lemma margins eciliate (10), or ciliolate (4), or ciliate (3). Lemma apex acute (10/15), or acuminate (4/15), or attenuate (1/15); without ornament (15), or pubescent (1); muticous (4), or awned (12); 1 -awned (12/12). Palea 1 length of lemma; 4 -veined (4/6), or 5 -veined (2/6), or 6 -veined (3/6), or 7–8 -veined (1/6), or 10–12 -veined (1/6). Palea keels wingless (15), or winged (1); eciliate (5), or ciliolate (11). Palea surface glabrous (13), or puberulous (3). Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2 (1), or 3 (15); membranous (14/14); glabrous (11), or ciliate (5); obtuse (1/1). Anthers 3. Stigmas 2. Ovary unappendaged (14), or umbonate (2); glabrous (2/2).

FRUIT Caryopsis with adherent pericarp (11/11). Embryo 0.2 length of caryopsis. Hilum linear (1/1); 1 length of caryopsis.

DISTRIBUTION North America (4), or South America (15).

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