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.

Isachne

HABIT Annual (32), or perennial (67). Rhizomes absent (92), or elongated (4). Stolons absent (94), or present (2). Culms erect (29/92), or geniculately ascending (32/92), or decumbent (30/92), or prostrate (15/92), or rambling (12/92), or leaning (1/92), or scandent (4/92); robust (2/16), or slender (11/16), or weak (3/16); 2–53.61–600 cm long; firm (88), or wiry (4), or woody (5); without nodal roots (2/35), or rooting from lower nodes (35/35). Culm-internodes terete (3/3). Culm-nodes swollen (1/1). Lateral branches lacking (4/30), or sparse (8/30), or ample (20/30), or fastigiate (1/30). Ligule an eciliate membrane (1), or a ciliate membrane (3), or a fringe of hairs (85), or absent (10). Leaf-blades linear (33), or lanceolate (74), or elliptic (8), or oblong (3), or ovate (17); membranous (2), or herbaceous (90), or coriaceous (4); stiff (15), or firm (80), or flaccid (1). Leaf-blade midrib indistinct (3/7), or evident (1/7), or conspicuous (3/7). Leaf-blade venation without cross veins (95), or with distinct cross veins (1). Leaf-blade margins unthickened (5/48), or cartilaginous (45/48). Leaf-blade apex muticous (95), or pungent (1).

INFLORESCENCE Inflorescence a panicle, or composed of racemes (1); terminal (95), or terminal and axillary (2); exserted (94), or embraced at base by subtending leaf (4).

Panicle open (89), or contracted (7), or spiciform (1).

Racemes single (1/1); paucilateral (1/1); bearing few fertile spikelets (1/1). Spikelet packing lax (1/1).

Spikelets appressed (1/2), or spreading (1/2); solitary (94), or in pairs (2). Fertile spikelets pedicelled. Pedicels filiform (24/27), or linear (1/27), or clavate (2/27); tip rectangular (1/4), or widened (3/4).

FERTILE SPIKELETS Spikelets comprising 0 basal sterile florets (2/21), or 1 basal sterile florets (21/21); 1 fertile florets (26), or 2 fertile florets (73); without rhachilla extension. Spikelets lanceolate (1), or elliptic (23), or oblong (8), or ovate (14), or orbicular (50), or obovate (21); of unremarkable solid shape (95), or globose (1); subterete (1), or dorsally compressed (95); 0.5–1.923–4.5 mm long; breaking up at maturity; disarticulating below each fertile floret (76), or above glumes but not between florets (20). Rhachilla internodes brief up to lowest fertile floret (92), or elongated between glumes (2), or elongated below proximal fertile floret (2); suppressed between florets (10/74), or definite (64/74); glabrous (62/64), or pubescent (2/64). Floret callus woolly (2/2).

GLUMES Glumes deciduous; shorter than spikelet (41), or reaching apex of florets (45), or exceeding apex of florets (15); thinner than fertile lemma; incurved at apex (1), or parallel to lemmas (93), or gaping (2). Lower glume lanceolate (9), or elliptic (19), or oblong (14), or ovate (54), or orbicular (14), or obovate (6); 0.8–0.9966–1.1 length of upper glume; membranous (90), or chartaceous (2), or herbaceous (4); without keels; 3 -veined (8/80), or 4 -veined (2/80), or 5 -veined (44/80), or 6 -veined (16/80), or 7 -veined (40/80), or 8 -veined (18/80), or 9 -veined (23/80), or 10–11 -veined (4/80). Lower glume lateral veins obscure (6), or distinct (90). Lower glume surface convex (95), or flat (1); smooth (89), or asperulous (5), or scabrous (4); without pits; glabrous (51), or puberulous (15), or pubescent (23), or pilose (4), or hirsute (1), or hispidulous (12), or hispid (5), or setose (3). Lower glume apex emarginate (1/95), or truncate (1/95), or obtuse (64/95), or acute (22/95), or acuminate (7/95), or cuspidate (5/95). Upper glume lanceolate (8), or elliptic (19), or oblong (7), or ovate (56), or orbicular (15), or obovate (8); 1–1.117–2 length of adjacent fertile lemma; membranous (90), or chartaceous (2), or herbaceous (4); with undifferentiated margins (87), or hyaline margins (9); without keels; 3 -veined (3/75), or 4 -veined (2/75), or 5 -veined (39/75), or 6 -veined (18/75), or 7 -veined (43/75), or 8 -veined (17/75), or 9 -veined (26/75), or 10–11 -veined (7/75). Upper glume surface smooth (90), or asperulous (5), or scabrous (3); glabrous (49), or puberulous (17), or pubescent (19), or pilose (8), or hirsute (1), or hispidulous (11), or hispid (5), or setose (4); with simple hairs (57/65), or tubercle-based hairs (8/65). Upper glume apex emarginate (1/95), or truncate (2/95), or obtuse (65/95), or acute (22/95), or acuminate (4/95), or attenuate (1/95), or cuspidate (5/95), or caudate (1/95).

FLORETS Basal sterile florets male (24/24); with palea (22/22). Lemma of lower sterile floret elliptic (11/22), or oblong (6/22), or ovate (9/22); 1–1.37–1.7 length of fertile lemma; membranous (5/18), or chartaceous (7/18), or herbaceous (2/18), or cartilaginous (2/18), or coriaceous (3/18); 5 -veined (5/6), or 6 -veined (1/6), or 7 -veined (2/6), or 8–9 -veined (1/6); without grooves (25/26), or sulcate (1/26); obtuse (9/11), or acute (2/11). Fertile florets bisexual (90), or female (11). Fertile lemma lanceolate (1), or elliptic (32), or oblong (9), or ovate (30), or orbicular (41), or obovate (8); hemispherical (5/5); chartaceous (4), or cartilaginous (10), or coriaceous (77), or indurate (6); without keel; wingless; 0 -veined (1/14), or 5 -veined (12/14), or 6 -veined (9/14), or 7 -veined (10/14), or 8–9 -veined (1/14). Lemma lateral veins obscure (11/11). Lemma surface smooth (93), or scabrous (1), or papillose (1), or punctate (1); unwrinkled (95), or rugulose (1); without grooves; glabrous (47), or puberulous (35), or pubescent (18), or pilose (1). Lemma margins involute; exposing palea (92), or interlocking with palea keels (4); eciliate (92), or ciliolate (1), or ciliate (1), or pubescent (3). Lemma apex obtuse (93), or acute (2), or acuminate (1); without ornament, or pubescent (1). Palea 1 length of lemma; membranous (1), or chartaceous (4), or cartilaginous (8), or coriaceous (78), or indurate (5); 0 -veined (1/78), or 2 -veined (77/78). Palea surface glabrous (87), or puberulous (5), or pubescent (4), or pilose (1).

FLOWER Lodicules 1 (1/7), or 2 (6/7); fleshy (4/4). Anthers 2 (1/80), or 3 (80/80).

FRUIT Caryopsis with adherent pericarp (78/78); ellipsoid (5/13), or oblong (1/13), or ovoid (4/13), or orbicular (3/13), or obovoid (1/13); laterally compressed (1/3), or dorsally compressed (2/3); plano-convex (3/3).

DISTRIBUTION Africa (14), or Temperate Asia (20), or Tropical Asia (59), or Australasia (4), or Pacific (9), or North America (3), or South America (12).

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