The grass genera of the world
Type species: Type: C. abyssinicus (A. Rich.) Hochst.
Excluding Crinipes (Triraphis) longipes = Nematopoa
Habit, vegetative morphology. Perennial; caespitose. Culms 45–160 cm high; herbaceous; unbranched above. Young shoots extravaginal. Leaves mostly basal; non-auriculate. Leaf blades narrowly linear to linear-lanceolate; narrow; 5–14 mm wide (in C. longifolius, up to 6 mm in C. abyssinicus); not setaceous; flat, or rolled (then convolute); not pseudopetiolate; without cross venation; disarticulating from the sheaths. Ligule a fringe of hairs.
Reproductive organization. Plants bisexual, all with bisexual spikelets; with hermaphrodite florets.
Inflorescence. Inflorescence paniculate (medium to large); open to contracted; more or less irregular; espatheate; not comprising partial inflorescences and foliar organs. Spikelets not secund; pedicellate.
Female-fertile spikelets. Spikelets compressed laterally; disarticulating above the glumes; disarticulating between the florets. Rachilla prolonged beyond the uppermost female-fertile floret; hairy; the rachilla extension with incomplete florets. Hairy callus present. Callus blunt.
Glumes two; very unequal; shorter than the spikelets; shorter than the adjacent lemmas (1/2 to 3/4 as long); without conspicuous tufts or rows of hairs; pointed (acuminate); awned to awnless (usually mucronate or short-awned); similar (thinly membranous). Lower glume 1 nerved. Upper glume 1 nerved. Spikelets with incomplete florets. The incomplete florets distal to the female-fertile florets. The distal incomplete florets merely underdeveloped. Spikelets without proximal incomplete florets.
Female-fertile florets 2–3. Lemmas narrowly ovate to narrowly oblong-ovate; not becoming indurated (scarious-membranous); entire to incised; when incised, 2 lobed; not deeply cleft (bidenticulate); awned. Awns 1; median; from a sinus, or apical; non-geniculate; straight, or flexuous; hairless (scaberulous); much longer than the body of the lemma. Lemmas hairy (but only between the lateral nerves and the margins); non-carinate (rounded on the back); 3 nerved; with the nerves non-confluent. Palea present; relatively long; awnless, without apical setae; textured like the lemma (thinly membranous); not indurated; 2-nerved; 2-keeled. Palea back glabrous. Palea keels wingless. Lodicules present; 2; free; fleshy; ciliate, or glabrous. Stamens 3. Anthers 2–2.5 mm long. Ovary apically glabrous. Styles free to their bases. Stigmas 2; brown (yellowish).
Fruit, embryo and seedling. Fruit free from both lemma and palea; small (1.8 to 2 mm long); compressed dorsiventrally (ventrally flat, dorsally convex). Hilum short (linear, but only 1/4 to 1/3 the length of the grain). Embryo small (1/4 to 1/3 the length of the grain).
Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous. Papillae absent. Long-cells markedly different in shape costally and intercostally (the costals narrower); of similar wall thickness costally and intercostally (fairly thick walled). Mid-intercostal long-cells regularly rectangular; having markedly sinuous walls (the sinuosity fine). Microhairs absent. Stomata absent or very rare (a few only seen, near the blade margin). Subsidiaries non-papillate; parallel-sided and dome-shaped. Guard-cells overlapping to flush with the interstomatals. Intercostal short-cells very common; not paired (solitary). Neither macrohairs nor prickles seen, except for prickles at the margins. Costal zones with short-cells. Costal short-cells conspicuously in long rows (but the short-cells fairly long). Costal silica bodies present and well developed; panicoid-type; consistently, conspicuously nodular.
Transverse section of leaf blade, physiology. C3; XyMS+ (the mestome sheath cells thick walled). Mesophyll with radiate chlorenchyma (especially around the smaller bundles); with adaxial palisade; Isachne-type (in places, especially around minor bundles). Leaf blade with distinct, prominent adaxial ribs; with the ribs very irregular in sizes (small over the smaller bundles, large and flat topped over the primaries). Midrib not readily distinguishable; with one bundle only. The lamina symmetrical on either side of the midrib. Bulliforms present in discrete, regular adaxial groups (in each furrow); in simple fans. All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present (with every bundle); forming figures (anchors with the smaller bundles, heavy Is with the primaries). Sclerenchyma not all bundle-associated. The extra sclerenchyma in abaxial groups (or rather, in the form of single cells); abaxial-hypodermal, the groups isolated (opposite the bulliforms, but not of universal occurrence).
Classification. Watson & Dallwitz (1994): Arundinoideae; Danthonieae. Soreng et al. (2015): Arundinoideae; Molinieae. 2 species.
Distribution, phytogeography, ecology. Ethiopia, Sudan, Uganda.
In rocky places.
References, etc. Morphological/taxonomic: Hubbard 1957. Leaf anatomical: this project.
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’.