Scientific taxonomy article
Accepted name and publication history
The accepted name in the current Kew backbone is Cereus spegazzinii F.A.C.Weber. Frédéric Albert Constantin Weber published the name in 1899 in Monatsschrift für Kakteenkunde 9: 102. IPNI supplies nomenclatural authorship and place of publication, while current acceptance, synonymy, and native distribution follow POWO's taxonomic opinion.12
The species name was published directly in Cereus, without a parenthetical basionym author. Later Monvillea and Piptanthocereus combinations record alternative generic treatments.
Taxon boundary and infraspecific treatment
In the Kaktüs Doktoru backbone, the species is a child of the genus Cereus. Kew lists no accepted subspecies or variety; the historical var. ebenacanthus and var. hassleri are included in species synonymy. This package updates only the canonical species node and its linked botanical-dictionary record; it does not flatten accepted subordinate ranks into species synonyms, rewrite the genus node, or alter the product.
Diagnostic characters
WFO and Flora do Brasil describe stems branching at ground level, often with decumbent or spreading shoots, green to glaucous epidermis, and usually 3–5 ribs. The flower tube is smooth and the fruit greenish to pinkish with deciduous perianth remnants. These characters must be assessed together. A product photograph is not an herbarium voucher, and cultivation may alter stem colour, spine density, and growth direction.
Phylogenetic context
The 2023 genus-level phylogeny investigated relationships within Cereus with hundreds of captured nuclear orthologues and a coalescent framework, demonstrating why traditional appearance-based circumscriptions require genomic testing.3 A 2025 family-wide phylogenomic study then reassessed the Cactaceae backbone and classification using hundreds of nuclear genes.4 These studies do not by themselves rename this species; they warn against inferring close relationship from one conspicuous stem or spine character.
Native distribution and conservation
Kew records the native range as Bolivia, Paraguay, west-central Brazil, and north-eastern Argentina.1 POWO treats the species as a succulent shrub of seasonally dry tropical biomes. Its decumbent or ground-level branching habit shows that not every Cereus species must form one strictly upright column. The stored conservation category is LC.5 The IUCN assessment is Least Concern. A broad regional range does not mean local dry habitats are immune to land conversion or collection, and commercial inventory is not evidence of wild-population status.
Synonymy and retrieval
Kew accepts 12 synonyms at the species node: Two homotypic Monvillea/Piptanthocereus combinations plus Cereus anisitsii, C. haageanus, C. lindenzweigianus, two historical varieties, and related generic combinations form the 12-name surface. These are not canonical routes; they document nomenclatural history and support retrieval of older literature. The name Cereus anisitsii K.Schum. must not be confused with the accepted Gymnocalycium anisitsii; genus and authorship must be read together.1
References
- Plants of the World Online. “Cereus spegazzinii F.A.C.Weber.” Royal Botanic Gardens, Kew. Accessed: 2026-08-04. https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:53304-2 ↩
- International Plant Names Index. “Cereus spegazzinii F.A.C.Weber.” Accessed: 2026-08-04. https://www.ipni.org/n/53304-2 ↩
- Taylor, N. P. et al. “A phylogeny of Cereus (Cactaceae) and the placement and description of two new species.” Taxon. https://doi.org/10.1002/tax.13103 ↩
- de Vos, J. M. et al. “Phylogenomics and classification of Cactaceae based on hundreds of nuclear genes.” Plant Systematics and Evolution 311:28 (2025). https://doi.org/10.1007/s00606-025-01948-z ↩
- IUCN Red List of Threatened Species. “Cereus spegazzinii.” https://www.iucnredlist.org/species/151795/121443548 ↩
- World Flora Online. “Cereus spegazzinii F.A.C.Weber.” Accessed: 2026-08-04. https://www.worldfloraonline.org/taxon/wfo-0000597692 ↩
