13.07   CYNOSURUS L.

REVISED TREATMENT. Please send comments to Mary Barkworth.
Sandy Long

Plants annual or perennial; sometimes rhizomatous. Culms 1.5-150 cm, erect. Cauline leaves 1-3; sheaths open to the base; auricles absent; ligules truncate, entire, erose, or ciliolate; blades flat. Inflorescences terminal panicles, panicles condensed, often spikelike, linear to almost globose, more or less unilateral. Spikelets subsessile to shortly pedicellate, laterally compressed, dimorphic, usually paired, distal spikelet on each branch sometimes solitary, proximal spikelet of each pair sterile, almost completely concealing the fertile spikelet; disarticulation above the glumes and beneath the florets. Sterile spikelets persistent; florets 6-18, reduced to narrow, linear-lanceolate lemmas, sometimes awned, awns terminal; glumes narrow, linear. Fertile spikelets adaxial to the sterile spikelets; florets 1-5; rachillas glabrous, extending beyond the distal floret; glumes 2, subequal and shorter than the spikelets, thin, lanceolate, 1-veined, acute, sometimes awned; calluses short, blunt, glabrous; lemmas glabrous or pubescent, 5-veined, acute or bidentate, unawned to conspicuously awned; paleas about as long as the lemmas, bifid; lodicules 2, free, glabrous, ovate, bilobed; anthers 3; ovaries broadly ellipsoid, glabrous; styles separate. Caryopses oblong-ellipsoid, subterete, slightly dorsally compressed, sometimes adherent to the paleas; hila 1/5-1/2 as long as the grain, oblong to linear. x = 7. Name from the Greek, kynos, dog, and oura, tail, referring to the shape of the panicle.

Cynosurus is a genus of eight species that grow in open, grassy, often weedy habitats. It is native around the Mediterranean and in western Asia. The affinities of the genus are obscure. Two species are established in the Flora region.

Cynosurus is similar to Lamarckia in having dimorphic spikelets.


SELECTED REFERENCES Ennos, R.A.1985. The mating system and genetic structure in a perennial grass, Cynosurus cristatus L. Heredity 55:121-126; Jirásek, V. and J. Chrtek. 1964. Zur frage des taxonomischen Wertes der Gattung CynosurusL. Novit. Bot. Delect. Seminum Horti Bot. Univ. Carol. Prag. 20:23-27; Lodge, R.W. 1959. Biological flora of the British Isles: Cynosurus cristatus L. J. Ecol. 47:511-518.

1
Plants perennial; panicles linear; fertile lemmas unawned or with awns less than 3 mm long ..... 1. C. cristatus
Plants annual; panicles ovoid to almost globose; fertile lemmas with awns 5-25 mm long ..... 2. C. echinatus


1.   Cynosurus cristatus L.
Crested Dogtail, Cynosure Accrêté, Crételle des Prés

Plants perennial; cespitose, not rhizomatous. Culms (5)15-75(90) cm. Sheaths smooth, glabrous; ligules 0.5-2.5 mm, truncate, erose or ciliolate; blades 3-15(19) cm long, 0.5-2(4.3) mm wide, glabrous or pubescent. Panicles (1)3.5-14 cm long, 0.4-1 cm wide, linear, spikelike, unilateral. Spikelets 3-7 mm, subsessile or shortly pedicellate, pedicels to 1 mm. Sterile spikelets strongly laterally compressed, with 6-11(18) florets; glumes and lemmas similar, linear-lanceolate, keeled, keels ciliate, apices acuminate to awned, awns to 1 mm. Fertile spikelets with 2-5 florets, glumes and lemmas dissimilar; glumes 2.8-5.1 mm long, 0.6-0.9 mm wide, 1-veined, laterally compressed, hyaline, keeled, acute; rachilla internodes 0.4-0.6 mm; lemmas 3-4.5 mm long, 0.6-1.1 mm wide,dorsally compressed, membranous to subcoriaceous, not keeled, margins hyaline, cilioliate, apices obtuse to acute, unawned or awned, awns to 3 mm; anthers 1.8-3 mm. 2n = 14.

Cynosurus cristatus is a European native that is now established in North America. It grows in a wide range of soils in dry or damp habitats. In Europe it is used for fodder and pasture, especially for sheep, but in North America it is regarded as a weedy species. It is self-incompatible.


2.   Cynosurus echinatus L.
Bristly Dogtail

Plants annual, tufted. Culms 9-150 cm, clustered or solitary. Sheaths smooth, glabrous; ligules 2.5-5(10) mm, obtuse, entire; blades 3-13.5(23) cm long, 2.5-14 mm wide, scabrous. Panicles 1-4(8) cm long, 0.7-2 cm wide, ovoid to almost globose, unilateral. Spikelets 7-14 mm; subsessile or shortly pedicellate, pedicels to 1.6 mm. Sterile spikelets with 6-18 florets; glumes and lemmas similar, subulate to linear-lanceolate, glabrous, sometimes scabridulous, awned, awns to 8 mm. Fertile spikelets with 1-5 florets, glumes and lemmas dissimilar; glumes 5.5-12 mm long, 0.4-0.9 mm wide, narrowly lanceolate, laterally compressed, hyaline, glabrous, 1-veined, keeled, awned, awns 0.5-2.2 mm; rachilla internodes 0.9-1.3 mm; lemmas 4-7 mm, slightly dorsally compressed, chartaceous or coriaceous, not keeled, lower 1/2 smooth, glabrous, distal 1/2 villous or scabrid, apices hyaline, ciliolate, entire or bidentate, awned, awns 5-18(25) mm; anthers 1-4 mm. 2n = 14.

Cynosurus echinatus is native to southern Europe. It is now established in North America, South America, and Australia. It usually grows in dry open habitats but has also been found at the edge of salt marshes.