The grass genera of the world
Habit, vegetative morphology. Annual. Culms 10–60 cm high; herbaceous; sparsely to amply branched above. The branching simple. Leaves not basally aggregated. Leaf blades linear; broad to narrow; 5–15 mm wide. Ligule an unfringed membrane.
Reproductive organization. Plants bisexual, all with bisexual spikelets; with hermaphrodite florets. The spikelets of sexually distinct forms on the same plant; hermaphrodite and male-only, or hermaphrodite and sterile. The male and female-fertile spikelets mixed in the inflorescence. The spikelets overtly heteromorphic; all in heterogamous combinations.
Inflorescence. Inflorescence of single, dorsiventral racemes terminating the culm branches. Rachides hollowed, or flattened. Inflorescence spatheate. Spikelet-bearing axes spikelike; solitary; with substantial rachides; disarticulating; disarticulating at the joints. Articles non-linear (inflated, clavate or turbinate); with a basal callus-knob; disarticulating transversely, or disarticulating obliquely. Spikelets paired; secund (the raceme dorsiventral, with the sessile members in two alternating rows on one side of the rachis); consistently in long-and-short combinations; in pedicellate/sessile combinations. Pedicels of the pedicellate spikelets discernible, but fused with the rachis. The shorter spikelets hermaphrodite. The longer spikelets male-only, or sterile (?).
Female-sterile spikelets. The pedicelled spikelets as large as the sessile, male or neuter, G1 smooth and asymmetrically or unilaterally winged, G2 variously keel-winged.
Female-fertile spikelets. Spikelets morphologically conventional (but the G1 curiously winged, ornamented and awned); abaxial; compressed dorsiventrally; falling with the glumes (and with the joint plus the pedicelled spikelet from the same joint, by contrast with Manisuris sensu stricto). Rachilla terminated by a female-fertile floret. Hairy callus absent.
Glumes present; two; long relative to the adjacent lemmas; hairy, or hairless; without conspicuous tufts or rows of hairs; awned (the G1 1–2 aristate or tailed), or awnless (G. clarkei); non-carinate; very dissimilar (the G1 hardened, curiously ornamented and winged above, and aristate). Lower glume two-keeled; convex on the back; lacunose with deep depressions, or rugose, or tuberculate, or prickly (and laterally winged above the middle). Spikelets with incomplete florets. The incomplete florets proximal to the female-fertile florets. The proximal incomplete florets 1; sterile. The proximal lemmas awnless; 0 nerved, or 2 nerved; similar in texture to the female-fertile lemmas (hyaline).
Female-fertile florets 1. Lemmas less firm than the glumes (hyaline); not becoming indurated; entire; awnless; 0 nerved, or 2 nerved. Palea present. Lodicules present; 2; fleshy. Stamens 3.
Fruit, embryo and seedling. Hilum short. Embryo large.
Transverse section of leaf blade, physiology. C4; XyMS.
Classification. Watson & Dallwitz (1994): Panicoideae; Andropogonodae; Andropogoneae; Rottboelliinae. Soreng et al. (2015): Panicoideae; Andropogonodae; Andropogoneae; Rottboelliinae. 8 species.
Distribution, phytogeography, ecology. Central and peninsular India.
Not known in Australasia.
References, etc. Morphological/taxonomic: Jain 1970.
Special comments. Anatomical data wanting.
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, and classifications. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., Macfarlane, T.D., and Dallwitz, M.J. 1992 onwards. The 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. Version: 13th November 2017. delta-intkey.com/grass’.