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| The genera of Cactaceae |
Including Cassytha Mill., Erythrorhipsalis A. Berger, Hariota Adans., Lymanbensonia Kimnach
The plants cerioid; not ‘low and very compacted’. The stems spiny (very rarely), or not spiny; usually elongate cylindric. The plants nearly always epiphytic, or lithophytic (rarely); producing aerial roots; mostly profusely branched; with cladodes (rarely), or without cladodes. The cladodes when present, with midribs. The plants pendent (usually), or prostrate; shrubby. The branches sometimes very slender, variously flattened, or cylindrical (mostly), or angled. The stems variously segmented; often annually articulating (the segments originating singly or in clusters at the tips of older segments); ribbed and grooved, or not ribbed and grooved. The ribs when present, longitudinal. The grooves relatively wide. The plants not conspicuously tuberculate, or conspicuously tuberculate to not conspicuously tuberculate (i.e., when flat and notched). The areoles usually not tubercle-associated; distant (sometimes absent terminally); spirally disposed, or borne along the margins of the flattened branches; simple; sparsely woolly; with bristles, or without bristles; nearly always without spines, or with spines (in that the numerous, minute areoles of Erythrorhipslis are furnished with bristle-like spines). The mature stems with much reduced leaves, or leafless. Leaves of mature stems when present, minute; membranous (minute scales).
Flowering at night and during the day (not closing at night). The flowers terminal (sometimes), or lateral; one per areole (usually), or more than one per areole; rotate; sessile; small to medium-sized; 0.2–2 cm long; regular. The receptacle and the ovary embedded in the branchlet, or free. The receptacle scarcely produced beyond the ovary, or not produced beyond the ovary; naked, or not naked; with scales, or without scales; spineless. The pericarpel round in cross section, usually naked but sometimes with small scales or areoles, rarely with soft bristles. The hypanthial tube ornamented like the pericarpel?; naked, or not naked; with scales, or without scales. The axils of the scales of the hypanthial tube more or less naked, or not naked. The hypanthial tube spineless. The perianth white (usually), or pink. The perianth segments relatively short, broad. Stamens exserted beyond the perianth. The stigma lobes white. The funicles short, not circinate.
The mature fruit small; usually globose; "white or coloured"; naked, or not naked (then with small scales or setose areoles); spiny; without persistent floral remains; fleshy (‘berry-like’); indehiscent (?). The seeds reddish brown to black; oblong; with perisperm (viscid); not encased in bony arils; with hilum and micropyle fused; with a mucilage sheath. The testa minutely rugose, or smooth, without ornamentation. Embryo slightly curved, or straight. Cotyledons reduced or vestigial (short, acute, the hypocotyl green and fleshy).
General anatomy. Cortical bundles commonly present (in various arrangements, often in the angles).
Natural Distribution. Mainly eastern Brazil, but throughout tropical America and the Caribbean, and also represented in tropical Africa, Madagascar and Sri Lanka.
Classification. About 36 species. Subfamily Cactoideae. Tribe Rhipsalideae.
Cf. Hunt (1967).
Images. • Rhipsalis pilocarpa: © Zoya Akulova (2012). • Rhipsalis pilocarpa: © Zoya Akulova (2012). • Rhipsalis baccifera subsp. schaferi, R. grandiflora, R. lindbergiana, R. pilocarpa (as Erythrorhipsalis): Britton & Rose (1923). • Hatiora salicornioides, Rhipsalis teres (as cribrata and R. heteroclada): Britton & Rose (1923). • Rhipsalis baccifera subsp. shaferi, R. mesembryanthemoides and M. neves-armondii (including megalantha), with Lepismium aculeata and L. lumbricoides (as Rhipsalis leucorhaphis): Britton & Rose (1923). • Rhipsalis teres (as R. capilliformis, R. heteroclada and R. virgata): Britton & Rose (1923). • Rhipsalis teres (as R. capilliformis), R. teres and R. cribrata = ?: Britton & Rose (1923). • Rhipsalis baccifera (as R. cassutha), R. cereuscula and R. burchellii: Britton & Rose (1923). • Rhipsalis neves-armondii, R. paradoxa, R. floccosa subsp. pulvinigera, R. flocosa subsp. tucamanensis: Britton & Rose (1923). • Rhipsalis dissimilis, R. floccosa (including gibberula), R. puniceo-discus: Britton & Rose (1923). • Rhipsalis grandiflora and R. pulchra: Britton & Rose (1923). • Rhipsalis dissimilis, R. teres (as heteroclada and prismatica) and ‘R. biformis = ?, with Pseudorhipsalis ramulosa (as R. coriacea): Britton & Rose (1923). • Rhipsalis crispata, R. elliptica and R. oblonga: Britton & Rose (1923). • Rhipsalis pachyptera, with R. rhombea = ?: Britton & Rose (1923). • Rhipsalis oblonga (as crispimarginata), R. pachyptera and R. russellii: Briton & Rose (1923). • seed and embryo of ‘Rhipsalis sp.’, with Pereskia grandiflora (Pfeiff) and ‘Epiphyllum coccineum’.
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’.
