The grass genera of the world
~ Arundinaria, Aulonemia
Type species: C. ulei (Hack.) Vianna, Clark & Filg.
Habit, vegetative morphology. Perennial; rhizomatous and caespitose. Culms erect, woody and persistent; not mottled, cylindrical; branched above to unbranched above. Buds from which the primary culm branches arise 1. Primary branches borne on promontories, 1–7; clumped. The branching apparently mostly simple (the branches each bearing 4–14 leaves). Culm nodes smooth or striate. Culm leaves present (clearly different from the foliage leaves). Culm leaf sheaths present; tardily deciduous; not conspicuously auriculate (but with auricular setae). Culm leaves with conspicuous blades. Culm leaf blades not pseudopetiolate, lanceolate to ovate, or triangular. Culm internodes hollow. Rhizomes pachymorph. Leaves auriculate; with auricular setae. Leaf blades lanceolate; leathery; broad to narrow; 2.7–8.7 cm long, 4–9 mm wide; pseudopetiolate; erect, cross veined. Ligule a fringed membrane; about 0.4 mm long. Contra-ligule present.
Reproductive organization. Plants bisexual, all with bisexual spikelets; with hermaphrodite florets. The spikelets hermaphrodite.
Inflorescence. Inflorescence determinate; a single spike to of spicate main branches, or paniculate (comprising spiciform branches appressed to the main axis); espatheate (the peduncle usually within a foliage leaf sheath); not comprising partial inflorescences and foliar organs. Spikelet-bearing axes racemes. Spikelets pedicellate (the pedicels 1.4–5.4 mm long).
Female-fertile spikelets. Spikelets morphologically conventional; 12–22 mm long; 2–3 mm wide, elliptic, or linear; slightly compressed laterally; disarticulating above the glumes; disarticulating between the florets; with conventional internode spacings. Rachilla prolonged beyond the uppermost female-fertile floret; the rachilla extension with incomplete florets.
Glumes two; very unequal; shorter than the spikelets; shorter than the adjacent lemmas; ciliate above, hairy to hairless (glabrous to puberulous); pointed; awned (both acuminate into the awn); non-carinate; similar. Lower glume about 0.7 times the length of the upper glume; 6–9 nerved. Upper glume 7–9 nerved. Spikelets with incomplete florets. The incomplete florets both distal and proximal to the female-fertile florets. The distal incomplete florets 1; merely underdeveloped; awned. Spikelets with proximal incomplete florets. The proximal incomplete florets 1; paleate. Palea of the proximal incomplete florets reduced. The proximal incomplete florets sterile. The proximal lemmas glumiform; awned; about 11 nerved; exceeded by the female-fertile lemmas; similar in texture to the female-fertile lemmas.
Female-fertile florets 2–4. Lemmas similar in texture to the glumes; white in fruit; entire; awned. Awns 1; median; apical; non-geniculate; straight (i.e., the lemma acuminate into the awn); hairless; much shorter than the body of the lemma; entered by one vein. Lemmas puberulous, hairless; 9–12 nerved; with the nerves non-confluent. Palea present; relatively long; not convolute; entire (apically acute to rounded,); awnless, without apical setae; several nerved (10 nerved); 2-keeled. Lodicules present; 3; free; membranous; ciliate; obovate to broadly elliptic, not toothed; heavily vascularized. Stamens 3. Anthers 6.2–8 mm long; not penicillate; without an apically prolonged connective. Ovary apically hairy; without a conspicuous apical appendage. Stigmas 2.
Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous. Papillae present (abundant); costal and intercostal. Intercostal papillae over-arching the stomata; consisting of one oblique swelling per cell, or several per cell. Microhairs absent. Stomata common. Without trichomes abaxially.
Transverse section of leaf blade, physiology. Lamina mid-zone in transverse section open.
C3; XyMS+. Mesophyll with non-radiate chlorenchyma; without adaxial palisade; without circular cells; not traversed by colourless columns; with arm cells; without fusoids. Leaf blade nodular in section to adaxially flat. Midrib conspicuous; with one bundle only, or having complex vascularization (?); without colourless mesophyll adaxially. The lamina symmetrical on either side of the midrib. Bulliforms present in discrete, regular adaxial groups; in simple fans. All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present; forming figures. Sclerenchyma all associated with vascular bundles (except in the blade margins). The lamina margins with fibres.
Classification. Watson & Dallwitz (1994): not described separately. Soreng et al. (2015): Bambusoideae; Bambusodae; Bambuseae; Arthrostylidiinae. 1 species (C. ulei).
Distribution, phytogeography, ecology. Southern Brazil.
Helophytic. In peaty bogs, less often in riparian vegetation.
References, etc. Morphological/taxonomic: Viana et al. (2013), Syst. Bot. 38. Leaf anatomical: Viana et al.
Special comments. Fruit 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’.