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.

Pseudoxytenanthera

HABIT Perennial. Rhizomes short; pachymorph. Culms erect (1/2), or scandent (1/2); 300–575–900 cm long; woody. Culm-internodes terete. Lateral branches dendroid. Branch complement several (1/2), or many (1/2); in a clump (1/1); with subequal branches (1/1), or 1 branch dominant (1/1); as thick as stem (1/1), or thinner than stem (1/1). Culm-sheaths deciduous but leaving a persistent girdle (1/1); auriculate (3/3). Culm-sheath blade linear (1), or lanceolate (2), or ovate (1), or triangular (1). Ligule an eciliate membrane. Leaf-blade base with a brief petiole-like connection to sheath. Leaf-blades linear (1), or lanceolate.

INFLORESCENCE Synflorescence bractiferous; clustered at the nodes; in globose clusters (4), or stellate clusters (1); with glumaceous subtending bracts; with axillary buds at base of spikelet; leafless between clusters.

Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 1 fertile florets (2), or 2 fertile florets (4), or 3 fertile florets (1); without rhachilla extension (3), or with diminished florets at the apex (2). Spikelets linear (1), or lanceolate (3), or ovate (1); laterally compressed; 10–16.8–25 mm long; falling entire (4), or breaking up at maturity (1); disarticulating above glumes but not between florets (1/1). Rhachilla internodes suppressed between florets (2/4), or definite (2/4).

GLUMES Glumes two (2), or several (3); persistent (1/1); shorter than spikelet. Lower glume ovate (1/1); chartaceous (1/1); without keels (1/1); 10–11 -veined (1/1). Lower glume surface without pits. Lower glume apex acuminate (1/1). Upper glume ovate; chartaceous (4/4); without keels (4/4); 5–7 -veined (1/2), or 10–11 -veined (1/2). Upper glume apex acuminate (4/4); muticous (1), or mucronate (4).

FLORETS Fertile lemma linear (1), or ovate (4); chartaceous; without keel; wingless; 13–16 -veined (1/1). Lemma surface unwrinkled; without grooves. Lemma margins flat (4), or convolute (1). Lemma apex acute (1), or acuminate (3), or apiculate (1); muticous (2), or mucronate (3). Palea 1 length of lemma; membranous (1), or chartaceous (4); 3–4 -veined (1/4), or 5 -veined (2/4), or 7 -veined (2/4); without keels (1), or 2-keeled but the uppermost without keels (3), or 2-keeled (1). Palea keels ciliolate (1/4), or ciliate (3/4). Apical sterile florets 1 in number (2/2); barren (2/2); linear (1/1).

FLOWER Lodicules absent. Anthers 6. Stigmas 1 (4), or 2–3 (2); plumose (3), or pubescent (2). Ovary umbonate; glabrous (2), or pubescent on apex (1), or pubescent all over (2).

FRUIT Caryopsis with adherent pericarp (4), or tardily free pericarp (1); linear (1/3), or fusiform (1/3), or oblong (1/3). Embryo 0.15 length of caryopsis. Hilum linear (4/4); 1 length of caryopsis.

DISTRIBUTION Tropical Asia.

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