Desmazeria Dumort.
Including Brizopyrum Link
Excluding Catapodium
Habit, vegetative morphology. Annual. Culms herbaceous. Culm internodes hollow. Leaves non-auriculate. Sheath margins free. Leaf blades linear; narrow; flat, or rolled (convolute when dry), or acicular; without cross venation; an unfringed membrane.
Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets; without hidden cleistogenes.
Inflorescence. Inflorescence a single raceme, or paniculate (one-sided, with few, stiff branches); espatheate; not comprising ‘partial inflorescences’ and foliar organs. Spikelet-bearing axes persistent. Spikelets not secund; pedicellate (the pedicels stout).
Female-fertile spikelets. Spikelets 4–22 mm long; compressed laterally; disarticulating above the glumes; disarticulating between the florets. Rachilla prolonged beyond the uppermost female-fertile floret; hairy (with capitate hairs); the rachilla extension with incomplete florets.
Glumes two; very unequal to more or less equal (the upper longer); (the longer) shorter than the adjacent lemmas, or long relative to the adjacent lemmas; dorsiventral to the rachis; hairless; awnless; carinate; similar (leathery). Lower glume 3 nerved. Upper glume 3–5 nerved. Spikelets with incomplete florets. The incomplete florets distal to the female-fertile florets. Spikelets without proximal incomplete florets.
Female-fertile florets 3–20. Lemmas similar in texture to the glumes; not becoming indurated; entire, or incised; when entire pointed, or blunt; awnless; hairy (below, with capitate hairs); carinate; 5(–7) nerved (the intermediates sometimes faint). Palea present; relatively long; 2-nerved; 2-keeled. Lodicules present; 2; free; membranous; glabrous; toothed, or not toothed; not or scarcely vascularized. Stamens 3. Anthers 0.8–1.4 mm long; not penicillate. Ovary glabrous; without a conspicuous apical appendage. Styles free to their bases. Stigmas 2; white.
Fruit, embryo and seedling. Fruit small (1.8–2.0 mm long); not grooved; compressed dorsiventrally. Hilum short. Embryo small. Endosperm hard; with lipid. Embryo with an epiblast.
Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous (the costal zones confined to a narrow median and a broader one at each margin of the blade). Papillae absent. Long-cells markedly different in shape costally and intercostally (the costals narrower and rectangular, with tessellated walls); differing markedly in wall thickness costally and intercostally (the costals thicker walled). Mid-intercostal long-cells fusiform; having straight or only gently undulating walls. Microhairs absent. Stomata absent or very rare (very few seen, confined to regions bordering the midrib); 37–51 microns long. Subsidiaries low dome-shaped, or parallel-sided. Guard-cells overlapped by the interstomatals. Intercostal short-cells absent or very rare. Costal short-cells predominantly paired (and solitary). Costal silica bodies poorly developed (in the material seen); tall-and-narrow (mostly, poorly developed and ill-defined).
Transverse section of leaf blade, physiology. C3; XyMS+. Mesophyll without adaxial palisade. Leaf blade with distinct, prominent adaxial ribs; with the ribs more or less constant in size. Midrib not readily distinguishable; with one bundle only. The lamina symmetrical on either side of the midrib. Bulliforms probably present in discrete, regular adaxial groups (at the bases of the furrows - unclear in the material seen); in simple fans. All the vascular bundles accompanied by sclerenchyma (but the sclerenchyma very scanty). Combined sclerenchyma girders absent (small, inconspicuous adaxial strands only). Sclerenchyma all associated with vascular bundles.
Cytology. Chromosome base number, x = 7. 2n = 14. 2 ploid.
Taxonomy. Pooideae; Poodae; Poeae.
Distribution, ecology, phytogeography. 5 species; Mediterranean, Europe. Commonly adventive. Xerophytic; species of open habitats. In sandy places.
Holarctic and Paleotropical. Boreal and Tethyan. African. Euro-Siberian. Macaronesian and Mediterranean. Saharo-Sindian. European.
References, etc. Morphological/taxonomic: Stace 1981, 1985; Brullo and Pavone 1985. Leaf anatomical: this project.
Special comments. No attempt here to account for Flora Europaea re-alignment (1980), involving Catapodium and Scleropoa.
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).