The grass genera of the world
Habit, vegetative morphology. Rather tall perennial; caespitose. Leaf blades cordate (often), or not cordate, not sagittate; pseudopetiolate (often), or not pseudopetiolate. Ligule an unfringed membrane.
Reproductive organization. Plants bisexual, all with bisexual spikelets; with hermaphrodite florets. The spikelets all alike in sexuality; homomorphic.
Inflorescence. Inflorescence of spicate main branches, or paniculate (the pedunculate racemes often whorled, sometimes basally branched); not comprising partial inflorescences and foliar organs. Spikelet-bearing axes racemes, or paniculate; with very slender rachides; persistent (despite being jointed). Articles not appendaged. Spikelets paired; pedicellate; consistently in long-and-short combinations; unequally pedicellate in each combination. Pedicels of the pedicellate spikelets free of the rachis. The shorter spikelets hermaphrodite. The longer spikelets hermaphrodite.
Female-fertile spikelets. Spikelets 4–6 mm long; not noticeably compressed (terete); falling with the glumes (from the pedicels). Rachilla terminated by a female-fertile floret. Hairy callus present (as a tuft of short hairs). Callus short.
Glumes two; more or less equal; long relative to the adjacent lemmas; without conspicuous tufts or rows of hairs; awnless; very dissimilar (the lower chartaceous, pallid, convex with raised nerves,the upper cymbiform). Lower glume not two-keeled; convex on the back; not pitted; relatively smooth; prominently 7 nerved, or 9 nerved (ridged). Upper glume 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, or epaleate; sterile. The proximal lemmas awnless; 1 nerved; more or less equalling the female-fertile lemmas; similar in texture to the female-fertile lemmas (hyaline).
Female-fertile florets 1. Lemmas less firm than the glumes (hyaline); not becoming indurated; incised; 2 lobed; deeply cleft; awned, or mucronate (in that the awn may be imperfect). Awns when present, 1; from a sinus; geniculate. Lemmas without a germination flap. Palea present; conspicuous but relatively short; nerveless (hyaline). Ovary apically glabrous. Stigmas 2.
Fruit, embryo and seedling. Fruit small (2 mm long); not noticeably compressed (cylindrical). Hilum short. Embryo large.
Transverse section of leaf blade, physiology. C4.
Cytology. 2n = 40.
Classification. Watson & Dallwitz (1994): Panicoideae; Andropogonodae; Andropogoneae; Andropogoninae. Soreng et al. (2015): Panicoideae; Andropogonodae; Andropogoneae. 4 species.
Distribution, phytogeography, ecology. Asia.
Rusts and smuts. Rusts Puccinia. Taxonomically wide-ranging species: Puccinia miyoshiana.
Special comments. Anatomical data wanting. Illustrations. • I. bambusoides and E. cotulifer : Flora of China 22 (2006)
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: 11th December 2017. delta-intkey.com/grass’.