| | The genera of Cactaceae |
Including Napina Fric (nom. inval.), Pseudosolisia Y. Itô (nom. inval.
The plants condensed-cactoid; low and very compacted in their entirety. The stems very spiny; globose, or shortly cylindric; 3–6 cm in diameter; not apically depressed. The plants unbranched, or offsetting; erect; solitary, or clustering; to 0.05–0.24 m high. The stems not segmented; not ribbed and grooved, or ribbed and grooved to not ribbed and grooved (the ribs poorly developed or absent). The plants conspicuously tuberculate. The tubercles well developed, conical, 3–10 mm long, 6–10 mm broad, 5–9 mm high; longitudinally grooved adaxially from the areole towards their ‘axils’. The tubercular groove extending more than halfway to the ‘axil’. The tubercles not connected by ribs (or scarcely so); more or less spirally disposed. The areoles associated with tubercles; distant; spirally disposed. The morphologically geminate, super-imposed buds separated, with the lower one in the axil of the conspicuous tubercle that bears the upper one at its tip. The areoles with the abaxial spine cluster at the tubercle tip connected to the adaxial floriferous meristem nearer its axil by a recessed linear isthmus or a ridge. The flowering areoles resembling the non-flowering ones. The areoles with spines. The spines clustered; 11–31; 0.5–2.5 cm long; with radials and centrals differentiated (the centrals variable, 5–25 mm long, black to reddish brown, straight and erect or sometimes absent, the radials 5–7 mm long, straight, radiating, white or whitish). Central spines (0–)1–2(–6). Radial spines 10–25. The spines straight. The mature stems leafless.
Flowering during the day. The flowers terminal (arising from the bases of the areolar grooves of young tubercles); one per areole; funnelform; sessile; small to medium-sized; 2–4 cm long (4–6 cm in diameter); regular. The receptacle conspicuously produced beyond the ovary into a tubular hypanthium; naked. The hypanthial tube naked; without scales; spineless. The perianth red, or pink (magenta). The perianth segments relatively short, broad; pointed.
The mature fruit 0.4–0.5 cm long; globose; greenish brown, or green; naked; non-fleshy when mature; indehiscent. The seeds 1–1.5 mm long; with an uneven lip over the hilum, black; pyriform; not encased in bony arils. The testa tuberculate. Cotyledons reduced or vestigial.
Natural Distribution. West Texas, Mexico.
Classification. Subfamily Cactoideae. Tribe Cacteae.
Cf. Hunt (1967).
Images. • Neolloydia conoidea and ‘N. ceratites’ = conoidea: Britton & Rose (1923). • Neolloydia conoidea (as texensis): Britton & Rose (1923).
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’.
