Cereeae is a tribe of

cacti A cactus (: cacti, cactuses, or less commonly, cactus) is a member of the plant family Cactaceae (), a family of the order Caryophyllales comprising about 127 genera with some 1,750 known species. The word ''cactus'' derives, through Latin, ...

belonging to the subfamily

Cactoideae The Cactoideae are the largest subfamily of the cactus family, Cactaceae, and are widely distributed throughout the Americas. Cactaceae is the 5th most endangered plant or animal family evaluated globally by the International Union for Conservati ...

containing about 50 genera, divided in 2023 among six subtribes.

Description

Cereeae are tree-like or shrubby, sometimes climbing plants. Their mostly elongated to spherical, ribbed and thorny shoots are not articulated. The flowers, which usually appear on the side of the shoot, open during the day or at night. Their pericarpels usually have a few scales or are completely glabrous. The fleshy, berry-like, bursting or non-bursting fruits often have a blackening adherent flower remnant. The small to large seeds are oval. The hilum and micropyle of the seeds are fused, one appendage is absent.

Taxonomy

Phylogeny

In classifications before the use of

molecular phylogenetic Molecular phylogenetics () is the branch of phylogeny that analyzes genetic, hereditary molecular differences, predominantly in DNA sequences, to gain information on an organism's evolutionary relationships. From these analyses, it is possible to ...

methods, Cereeae was one of nine tribes into which the subfamily

was divided. Molecular studies found that these traditional tribes were not

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

. A broader

circumscription Circumscription may refer to: * Circumscribed circle * Circumscription (logic) *Circumscription (taxonomy) * Circumscription theory, a theory about the origins of the political state in the history of human evolution proposed by the American anthr ...

of Cereeae, including Browningieae and Trichocereeae and comprising most columnar cacti of South American origin, was found to be monophyletic. With this circumscription, Cereeae was divided into three subtribes:

Rebutiinae The Rebutiinae are a subtribe of cactus, cacti belonging to the subfamily Cactoideae, tribe Cereeae. A 2010 classification accepted seven or eight genera, but when Circumscription (taxonomy), circumscribed in this way, the subtribe was not Monoph ...

Trichocereinae Trichocereinae is a subtribe of cactus that are particular to South America. There are 28 recognized genera in this subtribe. Description Arborescent to shrubby, Trichocereinae normally form unsegmented, spherical to columnar stems that are usual ...

and

Cereinae ''Cereinae'' is a subtribe of Cactus, cacti in the tribe Cereeae, subfamily Cactoideae. It is one of the six subtribes into which the tribe Cereeae was divided in 2023, the others being the monotypic Aylosterinae, Gymnocalyciinae, and Uebelmannii ...

, although Rebutiinae appeared not to be monophyletic. A 2021 study confirmed that Trichocereinae and Cereinae are monophyletic, but that Rebutiinae as then circumscribed was not. A 2023 study proposed six subtribes, which it found to be monophyletic. Rebutiinae was split into four subtribes: Aylosterinae, Gymnocalyciinae, Rebutiinae, and Uebelmanniinae. (Two genera, ''

Espostoopsis ''Espostoopsis'' is a monotypic genus of cactus containing the single species ''Espostoopsis dybowskii''. The generic name is formed from Greek ''opsis'' meaning "view", referring to its resemblance to the genus ''Espostoa'', with which it is oft ...

'' and '' Stetsonia'', were moved to different subtribes.) The study used a number of large datasets. Two genome-scale datasets agreed that the relationship among Rebutiinae, Trichocereinae, Gymnocalyciinae and Cereinae was as shown below. Limited coverage of the other two subtribes in the two datasets and low resolution in the analysis of a separate gene-based dataset meant that the study could not be certain as to which of Uebelmanniinae and Aylosterinae was the earliest diverging group, although the gene-based dataset suggested it was Uebelmanniinae.

Subtribes

Historically, the

of subtribes and genera in the Cereeae has been "highly controversial", and subject to considerable change. Six subtribes were proposed in a 2023 study. The table below compares the 2023 classification with a widely used 2010 classification. ,

Plants of the World Online Plants of the World Online (POWO) is an online taxonomic database published by the Royal Botanic Gardens, Kew. History Following the Convention on Biological Diversity, the Royal Botanic Gardens in Kew launched Plants of the World Online i ...

accepted some genera that were treated as synonyms in the 2010 and 2023 studies. These genera are included in the table together with a note of the name used in one or both of the studies.

References

Soffiatti, P.; Angyalossy, V. "Anatomy of Brazilian Cereeae (subfamily Cactoideae, Cactaceae): ''Arrojadoa'' Britton & Rose, ''Stephanocereus'' A. Berger and ''Brasilicereus'' Backeberg." ''Acta Botanica Brasilica'', v. 21, n. 4, 2007.
Caryophyllales tribes {{Cactus-stub