''Rhodocactus grandifolius'' (rose cactus; syn. ''Pereskia grandifolia'') is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

cactus 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, ...

native to eastern and southern

Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ...

. Like all species in the genus '' Rhodocactus'' and unlike most cacti, it has persistent leaves. It was first described in 1819. It is grown as an

ornamental plant Ornamental plants or ''garden plants'' are plants that are primarily grown for their beauty but also for qualities such as scent or how they shape physical space. Many flowering plants and garden varieties tend to be specially bred cultivars th ...

and has naturalized outside its native range.

Description

Although ''Rhodocactus grandifolius'' is a cactus by classification, it takes the form of a

shrub A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees by their multiple ...

or small

tree In botany, a tree is a perennial plant with an elongated stem, or trunk, usually supporting branches and leaves. In some usages, the definition of a tree may be narrower, e.g., including only woody plants with secondary growth, only ...

, in height, exceptionally . Young twigs are green or reddish with conspicuous white spots marking the

stoma In botany, a stoma (: stomata, from Greek language, Greek ''στόμα'', "mouth"), also called a stomate (: stomates), is a pore found in the Epidermis (botany), epidermis of leaves, stems, and other organs, that controls the rate of gas exc ...

ta. It has trunk has grayish-brown bark and has a diameter of up to . The

areole In botany, areoles are small light- to dark-colored bumps on cactus, cacti out of which grow clusters of Thorns, spines, and prickles, spines. Areoles are important diagnostic features of cactus, cacti, and identify them as a family distinct fr ...

s are rounded, cushion-shaped, and with grayish or brownish tomentum. On the twigs, they are across and up to on the main trunk. The areoles can have one to three or occasionally four leaves (brachyblast leaves) in addition to spines. The spines range from black to brown, the number at each areole gradually increasing with age; new twigs can have spineless areoles, while the trunk areoles may have up to 90 spines, each long. The leaves vary in size, and are usually from long, but can be shorter or up to long. They are entire, with shapes ranging from elliptic to ovate and obovate-lanceolate. The dense

inflorescence In botany, an inflorescence is a group or cluster of flowers arranged on a plant's Plant stem, stem that is composed of a main branch or a system of branches. An inflorescence is categorized on the basis of the arrangement of flowers on a mai ...

develops at the ends of stems and also laterally from the areoles of upper parts of the main shoots and twigs. It usually has 10-15 flowers, but sometimes has 30 or more. The flowers which may be pale pink through to purplish-pink are showy and rose-like, about across. The fruit is very variable in size and shape, and is green, yellowish or reddish-green when ripe. It contains many glossy black seeds. File:Pereskia grandifolia 24zz.jpg, Habit, in cultivation File:Pereskia grandifolia 42zz.jpg, Spines on stems

Taxonomy

The species was first described by

Adrian Hardy Haworth Adrian Hardy Haworth (19 April 1767, in Kingston upon Hull, Hull – 24 August 1833, in Chelsea, London, Chelsea) was an England, English entomologist, botanist and carcinologist. Family The younger son of Benjamin Haworth, of Haworth Hall and ...

in 1819 as ''Pereskia grandifolia''. It was transferred to ''Rhodocactus'' as ''R. grandifolius'' by Frederik Marcus Knuth in 1936. However, this was not accepted by most botanists, and ''Rhodocactus'' was sunk into a broadly circumscribed ''Pereskia''.

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 ...

studies from 2005 onwards suggested that with this circumscription, ''Pereskia'' was 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 ...

, and consisted of three clades. In 2016, the genus ''Rhodocactus'' was revived for one of these clades, which included ''R. grandifolius''.

Varieties

Two varieties are accepted: *''Rhodocactus grandifolius'' var. ''grandifolius'' is distinguished by having green

bract In botany, a bract is a modified or specialized leaf, associated with a reproductive structure such as a flower, inflorescence axis or cone scale. Bracts are usually different from foliage leaves in size, color, shape or texture. They also lo ...

s and green to pink

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 Etymology The term ''sepalum'' ...

-like

perianth The perianth (perigonium, perigon or perigone in monocots) is the non-reproductive part of the flower. It is a structure that forms an envelope surrounding the sexual organs, consisting of the calyx (sepals) and the corolla (petals) or tepal ...

parts. *''Rhodocactus grandifolius'' var. ''violaceus'' (Leuenb.) I.Asai & K.Miyata has purplish-pink or purple bracts and

-like

parts, and somewhat smaller

petal Petals are modified leaves that form an inner whorl surrounding the reproductive parts of flowers. They are often brightly coloured or unusually shaped to attract pollinators. All of the petals of a flower are collectively known as the ''corol ...

-like perianth parts than var. ''grandifolius''. It was discovered sometime before 1972, initially described as ''Pereskia bahiensis'', but is only distinguished by colour.

Distribution

The species as a whole is native to eastern and southern

. It is widely cultivated in other parts of South America, the

West Indies The West Indies is an island subregion of the Americas, surrounded by the Atlantic Ocean, North Atlantic Ocean and the Caribbean Sea, which comprises 13 independent island country, island countries and 19 dependent territory, dependencies in thr ...

and beyond, and has become naturalized in some of these countries, including

Vietnam Vietnam, officially the Socialist Republic of Vietnam (SRV), is a country at the eastern edge of mainland Southeast Asia, with an area of about and a population of over 100 million, making it the world's List of countries and depende ...

. ''R. grandifolius'' var. ''grandifolius'' has a similar distribution; ''R. grandifolius'' var. ''violaceus'' is apparently native to

Espírito Santo Espírito Santo (; ) is a state in southeastern Brazil. Its capital is Vitória, and its largest city is Serra. With an extensive coastline, the state hosts some of the country's main ports, and its beaches are significant tourist attracti ...

and

Minas Gerais Minas Gerais () is one of the 27 federative units of Brazil, being the fourth largest state by area and the second largest in number of inhabitants with a population of 20,539,989 according to the 2022 Brazilian census, 2022 census. Located in ...

, but is cultivated in neighbouring states.

Uses

''Rhodocactus grandifolius'' is grown as an

, appreciated for its flowers. It is also used as a hedge. Its leaves can be eaten as a salad or used in stews.

References

{{Taxonbar, from1=Q106617871, from2=Q134266 Pereskioideae Endemic flora of Brazil Cacti of South America Flora of Northeast Brazil Flora of Southeast Brazil Flora of South Brazil