Cymbosetaria Schweick.
Sometimes referred to Setaria
Habit, vegetative morphology. Annual. Culms 15–60 cm high; herbaceous; unbranched above (branching near the base). Leaves not basally aggregated; without auricular setae. Leaf blades lanceolate; broad; sagittate; flat; pseudopetiolate (except the uppermost); rolled in bud, or once-folded in bud (? - supposedly ‘not pleated’); a fringed membrane (usually), or an unfringed membrane (rarely).
Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets.
Inflorescence. Inflorescence of spicate main branches; open; non-digitate. Inflorescence with axes ending in spikelets, or axes not ending in spikelets (depending on interpretation of the ‘bristle’). Inflorescence espatheate; not comprising ‘partial inflorescences’ and foliar organs. Spikelet-bearing axes persistent. Spikelets subtended by solitary ‘bristles’ (each subtended by a bristle). The ‘bristles’ persisting on the axis. Spikelets solitary; secund; pedicellate. Pedicel apices discoid.
Female-fertile spikelets. Spikelets abaxial; compressed dorsiventrally; falling with the glumes. Rachilla terminated by a female-fertile floret. Hairy callus absent.
Glumes two; relatively large; very unequal; shorter than the adjacent lemmas; dorsiventral to the rachis; hairless; awnless (G2 apiculate); non-carinate; very dissimilar. Lower glume 3 nerved. Upper glume 5–7 nerved. Spikelets with incomplete florets. The incomplete florets proximal to the female-fertile florets. Spikelets with proximal incomplete florets. The proximal incomplete florets 1; paleate. Palea of the proximal incomplete florets fully developed. The proximal incomplete florets male. The proximal lemmas awnless; not becoming indurated (textured like the G2).
Female-fertile florets 1. Lemmas cymbiform; decidedly firmer than the glumes; rugose; becoming indurated (crustaceous); entire; pointed, or blunt; awnless (but ‘sub-apiculate’); hairless; carinate; having the margins inrolled against the palea; with a clear germination flap; 3 nerved. Palea present; relatively long; entire; awnless, without apical setae (glabrous); textured like the lemma (crustaceous); indurated; 2-nerved; keel-less (flat backed). Lodicules present; free; fleshy; glabrous; not or scarcely vascularized. Stamens 3. Anthers not penicillate; without an apically prolonged connective. Ovary glabrous. Stigmas 2.
Fruit, embryo and seedling. Fruit small (1.25 mm long); compressed dorsiventrally (ventrally concave). Hilum short. Embryo large.
Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous. Papillae absent. Long-cells markedly different in shape costally and intercostally (the intercostals much broader). Mid-intercostal long-cells rectangular; having markedly sinuous walls. Microhairs present; panicoid-type. Stomata common. Subsidiaries low to high dome-shaped and triangular. Guard-cells overlapping to flush with the interstomatals. Intercostal short-cells absent or very rare. Costal short-cells conspicuously in long rows. Costal silica bodies ‘panicoid-type’; dumb-bell shaped and nodular.
Transverse section of leaf blade, physiology. C4; XyMS–. PCR cell chloroplasts centrifugal/peripheral. Leaf blade ‘nodular’ in section to adaxially flat. Midrib conspicuous (with a large abaxial keel); having a conventional arc of bundles (including 3 major bundles); with colourless mesophyll adaxially. Bulliforms not present in discrete, regular adaxial groups (seemingly, in the poor material seen). Many of the smallest vascular bundles unaccompanied by sclerenchyma. Combined sclerenchyma girders present (with the major bundles). Sclerenchyma all associated with vascular bundles.
Taxonomy. Panicoideae; Panicodae; Paniceae.
Distribution, ecology, phytogeography. 1 species; Africa. Mesophytic; shade species; glycophytic.
Paleotropical. African and Madagascan. Sudano-Angolan and Namib-Karoo. Somalo-Ethiopian, South Tropical African, and Kalaharian.
References, etc. Morphological/taxonomic: Schweickerdt 1936. Leaf anatomical: this project.
Illustrations. • Abaxial epidermis of leaf blade. Cymbosetaria sagittifolia.
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).
