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.

Chrysopogon

HABIT Annual (2), or perennial (46). Rhizomes absent (38), or short (9), or elongated (1). Stolons absent (47), or present (1). Culms erect (32/34), or geniculately ascending (6/34); robust (2/4), or slender (2/4); 10–101.1–300 cm long; firm (46), or wiry (2). Culm-internodes terete (1/1). Lateral branches lacking (4/7), or sparse (2/7), or ample (2/7), or fastigiate (1/7). Leaves differentiated into sheath and blade (46), or without demarcation between sheath and blade (2). Leaf-sheath auricles absent (47), or erect (1). Ligule an eciliate membrane (4), or a ciliolate membrane (10), or a ciliate membrane (3), or a fringe of hairs (31). Leaf-blades aciculate (1), or filiform (2), or linear (46), or lanceolate (1); herbaceous (47), or coriaceous (1); stiff (15), or firm (33). Leaf-blade midrib widened (1/1).

INFLORESCENCE Inflorescence a panicle with branches tipped by a raceme; terminal (47), or terminal and axillary (1).

Panicle open (40), or contracted (10). Primary panicle branches not whorled (15), or whorled at lower nodes (4), or whorled at most nodes (31).

Racemes bearing a triad of spikelets (36), or few fertile spikelets (12), or many spikelets (5); 1 fertile spikelets on each (36/45), or 2 fertile spikelets on each (7/45), or 3 fertile spikelets on each (11/45), or 4 fertile spikelets on each (7/45), or 5 fertile spikelets on each (6/45), or 6 fertile spikelets on each (4/45), or 7 fertile spikelets on each (2/45), or 8–13 fertile spikelets on each (1/45). Rhachis evident (19), or obsolete (33); tough (31), or fragile at the nodes (17); flattened (2/2). Rhachis internodes indefinite (2/19), or filiform (12/19), or linear (5/19). Rhachis internode tip transverse (4/15), or oblique (12/15); flat (1/5), or cupuliform (4/5). Raceme-bases brief (34), or filiform (14).

Spikelets appressed (11/11); in pairs (17), or in threes (36). Fertile spikelets sessile; 1 in the cluster. Companion sterile spikelets pedicelled; 1 in the cluster (17), or 2 in the cluster (36). Pedicels filiform (14), or linear (34).

STERILE SPIKELETS Companion sterile spikelets represented by single glumes (1), or rudimentary (1), or well-developed (47); persistent (1), or separately deciduous (47). Companion sterile spikelet glumes muticous (25/44), or mucronate (3/44), or awned (21/44).

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; without rhachilla extension. Spikelets linear (11), or lanceolate (17), or elliptic (3), or oblong (23); laterally compressed (46), or subterete (2); 3.32–6.812–15 mm long; falling entire; deciduous with accessory branch structures. Spikelet callus square (5), or oblong (5), or cuneate (29), or linear (9); glabrous (1), or pubescent (7), or pilose (17), or bearded (23); base truncate (1/45), or obtuse (12/45), or acute (10/45), or pungent (22/45); attached obliquely (14/18), or inserted (4/18).

GLUMES Glumes reaching apex of florets (12), or exceeding apex of florets (36); firmer than fertile lemma. Lower glume subulate (1), or linear (1), or lanceolate (21), or elliptic (2), or oblong (26); chartaceous (2), or cartilaginous (30), or coriaceous (16); without keels; 3 -veined (3/23), or 4 -veined (6/23), or 5 -veined (18/23), or 6 -veined (10/23), or 7 -veined (12/23), or 8 -veined (2/23), or 9 -veined (1/23). Lower glume lateral veins obscure (2), or distinct (46). Lower glume surface smooth (24), or asperulous (1), or scabrous (7), or spinose (16), or tuberculate (1), or muricate (2); without pits; glabrous (34), or pubescent (1), or pilose (3), or hispidulous (10), or hispid (1). Lower glume apex entire (46), or dentate (7); 2 -fid (7/7); emarginate (2/14), or truncate (5/14), or obtuse (3/14), or acute (4/14), or attenuate (1/14); muticous (45), or mucronate (6), or awned (2). Upper glume linear (1), or lanceolate (40), or elliptic (1), or oblong (8); chartaceous (9/17), or cartilaginous (2/17), or coriaceous (6/17); with undifferentiated margins (45), or hyaline margins (3); without keels (1), or 1-keeled (47); 3 -veined (14/14), or 4–5 -veined (7/14). Upper glume primary vein eciliate (37), or ciliolate (8), or ciliate (4), or pectinately ciliate (1), or pubescent (1). Upper glume surface smooth (41), or asperulous (2), or scabrous (6); glabrous (43), or puberulous (2), or pilose (3), or hispidulous (1), or hispid (1). Upper glume apex entire (46), or dentate (2); 2 -fid (2/2); emarginate (3/15), or truncate (1/15), or obtuse (8/15), or acute (1/15), or acuminate (2/15), or setaceously attenuate (1/15); muticous (10), or mucronate (10), or awned (38); 1 -awned (36/37), or 2 -awned (1/37).

FLORETS Basal sterile florets male (1), or barren (47); with palea (1), or without significant palea (47). Lemma of lower sterile floret lanceolate (23/47), or elliptic (1/47), or oblong (18/47), or obovate (5/47); 1 length of fertile lemma; hyaline; 0 -veined (1/39), or 2 -veined (36/39), or 3 -veined (3/39); emarginate (2/6), or truncate (1/6), or obtuse (2/6), or acute (2/6). Fertile lemma linear (15), or lanceolate (1), or oblong (34); hyaline; without keel; wingless; 0 -veined (4/23), or 1 -veined (9/23), or 3 -veined (10/23). Lemma lateral veins extending close to apex (1/1). Lemma surface unwrinkled; without grooves. Lemma margins eciliate (43), or ciliolate (4), or ciliate (1). Lemma apex entire (13), or dentate (36); 2 -fid (36/36); emarginate (2/4), or acute (1/4), or acuminate (1/4); muticous (2), or awned (46); 1 -awned (46/46). Principal lemma awn apical (10/46), or from a sinus (37/46); straight (5/46), or curved (1/46), or flexuous (5/46), or geniculate (37/46). Column of lemma awn glabrous (11/39), or hispidulous (2/39), or puberulous (15/39), or pubescent (14/39). Palea present (25), or absent or minute (23); 0.3–0.4313–0.8 length of lemma; hyaline (11/25), or membranous (14/25); 0 -veined (11/12), or 1 -veined (2/12), or 2 -veined (3/12); without keels (9/25), or 2-keeled (16/25). Palea surface glabrous (24/25), or puberulous (2/25).

FLOWER Lodicules 2 (10/10); truncate (1/1). Anthers 2 (2/26), or 3 (26/26).

FRUIT Caryopsis with adherent pericarp (13/13); fusiform (1/3), or oblong (2/3).

DISTRIBUTION Europe (1), or Africa (9), or Temperate Asia (8), or Tropical Asia (34), or Australasia (10), or Pacific (2), or North America (2), or South America (3).

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