Grass Genera of the World

L. Watson and M. J. Dallwitz


Stilpnophleum Nevski

Sometimes referred to Deyeuxia, Calamagrostis

Habit, vegetative morphology. Perennial; caespitose. Culms herbaceous. Leaves non-auriculate. Sheath margins free. Leaf blades narrow; without cross venation; ligule present; an unfringed membrane; not truncate; 3–8 mm long.

Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets.

Inflorescence. Inflorescence paniculate; contracted; capitate to spicate; espatheate; not comprising ‘partial inflorescences’ and foliar organs. Spikelet-bearing axes persistent. Spikelets not secund; pedicellate.

Female-fertile spikelets. Spikelets 5–7 mm long; not noticeably compressed; disarticulating above the glumes. Rachilla prolonged beyond the uppermost female-fertile floret; hairy; the rachilla extension naked. Hairy callus present.

Glumes two; more or less equal; long relative to the adjacent lemmas; pointed (acute to acuminate); awnless; carinate; similar (lanceolate or lanceolate-ovate). Lower glume 1 nerved. Upper glume 1 nerved. Spikelets with female-fertile florets only; without proximal incomplete florets.

Female-fertile florets 1. Lemmas similar in texture to the glumes; not becoming indurated; incised; not deeply cleft (toothed?); awned. Awns 1; median; dorsal; usually from well down the back; geniculate. Lemmas hairless; non-carinate; without a germination flap; 5 nerved. Palea present; relatively long; 2-nerved; 2-keeled, or keel-less. Lodicules present; 2; free; membranous; glabrous; usually toothed; not or scarcely vascularized. Stamens 3. Ovary glabrous. Styles free to their bases. Stigmas 2.

Fruit, embryo and seedling. Fruit longitudinally grooved. Hilum short. Embryo small.

Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous. Papillae absent. Mid-intercostal long-cells fusiform (mostly); having markedly sinuous walls (some, slightly), or having straight or only gently undulating walls. Microhairs absent. Stomata common; (33–)36–42(–45) microns long. Subsidiaries parallel-sided. Guard-cells overlapped by the interstomatals (clearly sunken). Intercostal short-cells absent or very rare. Prickles present over the veins. Costal short-cells neither distinctly grouped into long rows nor predominantly paired. Costal silica bodies horizontally-elongated crenate/sinuous and horizontally-elongated smooth; not sharp-pointed.

Transverse section of leaf blade, physiology. C3; XyMS+. Mesophyll without adaxial palisade. Leaf blade with distinct, prominent adaxial ribs to ‘nodular’ in section; with the ribs very irregular in sizes (large alternating with small). Midrib not readily distinguishable; with one bundle only. Bulliforms present in discrete, regular adaxial groups; in simple fans. All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present (with the primaries); forming ‘figures’. Sclerenchyma all associated with vascular bundles.

Taxonomy. Pooideae; Poodae; Aveneae.

Distribution, ecology, phytogeography. 1 species; Russia.

Holarctic. Tethyan. Irano-Turanian.

References, etc. Leaf anatomical: this project.


Cite this publication as: Watson, L., and Dallwitz, M. J. (1992 onwards). ‘Grass Genera of the World: Descriptions, Illustrations, Identification, and Information Retrieval; including Synonyms, Morphology, Anatomy, Physiology, Phytochemistry, Cytology, Classification, Pathogens, World and Local Distribution, and References.’ http://biodiversity.uno.edu/delta/. Version: 18th August 1999. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993 onwards, 1998), and Watson and Dallwitz (1994), and Watson, Dallwitz, and Johnston (1986) should also be cited (see References).

Index