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.

Aulonemia

HABIT Perennial. Rhizomes absent (2), or short (42); pachymorph (42/42). Culms erect (20/30), or geniculately ascending (1/30), or decumbent (1/30), or arching (1/30), or leaning (4/30), or scandent (12/30); 30–377.4–6700 cm long; woody. Culm-internodes alternately elongated and bunched (1/1); terete. Culm-nodes swollen (3/3); without obvious supra-nodal ridge (21/25), or with distinct supra-nodal ridge (5/25). Lateral branches suffrutescent (2), or dendroid (42). Branch complement one (25/29), or two (2/29), or three (1/29), or several (1/29), or many (3/29); solitary (19/21), or in a clump (2/21); at the node (43), or subtended by a bare patch above the node (1); with subequal branches (1/2), or 1 branch dominant (1/2); as thick as stem (6/6). Culm-sheaths persistent (4/8), or tardily deciduous (2/8), or deciduous (2/8); without auricles (3/5), or auriculate (2/5). Culm-sheath blade inconspicuous (1/10), or linear (1/10), or lanceolate (7/10), or triangular (2/10); constricted at base (1/2), or narrower than sheath (1/2). Leaf-sheath auricles absent (37), or erect (6), or falcate (3). Ligule an eciliate membrane (35), or a ciliolate membrane (5), or a ciliate membrane (1), or absent (4). Leaf-blade base with a brief petiole-like connection to sheath. Leaf-blades persistent (40), or deciduous at the ligule (4); linear (2), or lanceolate (35), or oblong (3), or ovate (17); herbaceous (41), or coriaceous (3); stiff (1), or firm (43); without exudate (43), or viscid (1). Leaf-blade midrib indistinct (1/1). Leaf-blade venation without cross veins (38), or with distinct cross veins (6). Leaf-blade margins cartilaginous (7/7).

INFLORESCENCE Synflorescence on the same culm as leaves (41/42), or on a separate leafless culm (1/42). Inflorescence a panicle (41/42), or composed of racemes (1/42); terminal (41/42), or terminal and axillary (1/42); exserted (41/42), or embraced at base by subtending leaf (1/42).

Panicle open (39/41), or contracted (2/41).

Racemes single (1/1); paucilateral (1/1). Rhachis angular (1/1). Spikelet packing broadside to rhachis (1/1).

Spikelets appressed (1/2), or ascending (1/2), or spreading (1/2); solitary (42/42). Fertile spikelets sessile (1/42), or pedicelled (42/42). Pedicels filiform (9/9).

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets (11/13), or 2–4 basal sterile florets (1/13); 2–6–23 fertile florets; with diminished florets at the apex (42/42). Spikelets linear (31/41), or lanceolate (2/41), or elliptic (1/41), or oblong (9/41); laterally compressed (30/42), or subterete (12/42); 8.3–25.99–70 mm long; breaking up at maturity (42/42); disarticulating below each fertile floret (42/42). Rhachilla internodes brief up to lowest fertile floret (41/42), or elongated below proximal fertile floret (1/42); definite (42/42); glabrous (40/42), or pubescent (3/42). Floret callus brief (39/42), or evident (3/42).

GLUMES Glumes two (38/42), or several (5/42); persistent (42/42); shorter than spikelet (42/42); thinner than fertile lemma (38/42), or similar to fertile lemma in texture (4/42). Lower glume lanceolate (30/41), or ovate (12/41); 0.33–0.6064–1 length of upper glume; membranous (40/41), or chartaceous (1/41); without keels (40/40); 1 -veined (16/37), or 2 -veined (5/37), or 3 -veined (22/37), or 4 -veined (9/37), or 5 -veined (8/37), or 6 -veined (1/37), or 7 -veined (4/37). Lower glume lateral veins absent (16/42), or obscure (3/42), or distinct (28/42). Lower glume surface without pits (42/42); glabrous (34/42), or puberulous (5/42), or pubescent (4/42). Lower glume apex obtuse (5/39), or acute (31/39), or acuminate (2/39), or attenuate (1/39), or setaceously attenuate (1/39); muticous (27/41), or mucronate (7/41), or awned (9/41). Upper glume linear (1/42), or lanceolate (20/42), or ovate (22/42); 0.3–0.5358–0.75 length of adjacent fertile lemma; membranous (41/41); without keels (39/41), or 1-keeled (2/41), or 2-keeled (1/41); 3 -veined (10/36), or 4 -veined (7/36), or 5 -veined (20/36), or 6 -veined (12/36), or 7 -veined (23/36), or 8 -veined (1/36), or 9–10 -veined (2/36), or 11 -veined (3/36). Upper glume surface glabrous (32/42), or puberulous (7/42), or pubescent (6/42). Upper glume apex entire (42/42), or dentate (1/42); 2 -fid (1/1); obtuse (14/39), or acute (21/39), or acuminate (5/39), or setaceously attenuate (1/39); muticous (31/42), or mucronate (4/42), or awned (9/42); 1 -awned (9/9).

FLORETS Basal sterile florets barren (13/13); with palea (2/13), or without significant palea (11/13). Lemma of lower sterile floret lanceolate (6/13), or elliptic (1/13), or oblong (1/13), or ovate (5/13); membranous (2/2); 3–4 -veined (2/10), or 5 -veined (6/10), or 6 -veined (3/10), or 7 -veined (7/10), or 8–9 -veined (4/10); obtuse (2/8), or acute (6/8); muticous (7/13), or mucronate (1/13), or awned (5/13). Fertile lemma lanceolate (24/42), or elliptic (2/42), or oblong (6/42), or ovate (11/42); chartaceous (34/42), or herbaceous (6/42), or coriaceous (2/42); without keel (42/42); wingless (42/42); 5 -veined (6/39), or 6 -veined (5/39), or 7 -veined (32/39), or 8 -veined (13/39), or 9 -veined (19/39), or 10–11 -veined (6/39), or 12–15 -veined (1/39). Lemma lateral veins obscure (2/2). Lemma surface smooth (38/42), or scaberulous (3/42), or scabrous (1/42); unwrinkled (42/42); without grooves (42/42); glabrous (24/42), or puberulous (13/42), or pubescent (6/42), or hirsute (1/42). Lemma margins eciliate (35/42), or ciliolate (3/42), or ciliate (4/42). Lemma apex obtuse (8/40), or acute (27/40), or acuminate (3/40), or setaceously attenuate (1/40), or apiculate (2/40); muticous (26/42), or pungent (1/42), or mucronate (5/42), or awned (13/42); 1 -awned (14/14). Principal lemma awn straight (18/18), or curved (1/18). Palea 0.8–0.9875–1.1 length of lemma; 2 -veined (4/8), or 3 -veined (2/8), or 4 -veined (5/8), or 6 -veined (1/8). Palea keels wingless (41/42), or winged (1/42); smooth (38/42), or scaberulous (1/42), or scabrous (3/42); eciliate (24/42), or ciliolate (14/42), or ciliate (4/42). Palea surface glabrous (35/42), or puberulous (2/42), or pubescent (5/42). Palea apex dentate (3/3). Apical sterile florets resembling fertile though underdeveloped (30/42), or distinct from fertile (12/42).

FLOWER Lodicules 3 (40/40); glabrous (23/40), or ciliate (17/40). Anthers 2 (1/41), or 3 (40/41). Stigmas 2 (38/38). Ovary unappendaged (41/42), or umbonate (1/42); glabrous (1/3), or pubescent on apex (1/3), or pubescent all over (1/3).

FRUIT Caryopsis with adherent pericarp (33/33); oblong (2/3), or ovoid (1/3). Embryo 0.66 length of caryopsis. Hilum linear (1/1); 1 length of caryopsis.

DISTRIBUTION North America (1), or South America (43).

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