| | The genera of Cactaceae |
The plants succulent; more or less conventionally dicotyledonous and leafy to 'cactoid'; more or less opuntioid; not ‘low and very compacted’. The stems spiny. The plants branched (the generally whorled branches readily detaching); without cladodes; erect; small shrubby, or tree-like; solitary; to 3 m high. The branches shorter than the main stems. The main stem more or less cylindrical. The branches cylindrical. The stems not segmented; not ribbed and grooved. The plants not conspicuously tuberculate. The areoles not tubercle-associated; distant; spirally disposed, or scattered on the surfaces; simple; white hairy; with glochids (and slender subsidiary spines); with spines. The spines clustered; 1-many; from "short" to 7 cm long; showing little or no difference between radials and centrals; short; white. The mature stems with well developed leaves (subsequently deciduous). Leaves of mature stems small to medium-sized (1–7 cm long); fleshy (broadly ovate or obovate to almost round, pointed or apiculate); fairly flat (with no midrib).
Flowering during the day. The flowers subterminal to terminal; one per areole; rotate; sessile; small to medium-sized; 1.5–4 cm long; regular. The receptacle not produced beyond the ovary; not naked. The pericarpel bearing leaflike scales subtending areoles with glochids and spines. The hypanthial tube lacking, the receptacle not produced beyond the ovary. The perianth showy, rotate; red, or pink. The perianth segments relatively short, broad; blunt. Stamens adnate to the perianth (inserted a the base). Gynoecium inferior. Placentation parietal. The funicles circinate.
The mature fruit ellipsoidal; naked (? - smooth, terete); without spines; fleshy; indehiscent (?). The seeds large, covered with the bony aril white; not hairy; round, flattened; encased in their bony arils. Cotyledons fleshy, foliaceous.
Natural Distribution. Arid, at lower altitudes in Bolivia, Paraguay and northwest Argentina. South America.
Classification. 2 species. Subfamily Opuntioideae. Tribe Cylindropuntieae.
Cf. Hunt (1967).
Images. • Quiabentia verticillata: www.flickr.com.
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, and distributions of character states within any set of taxa. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2018 onwards. The genera of Cactaceae: descriptions, illustrations, identification, and information retrieval. Version: 14th November 2021. delta-intkey.com’.
