Capsicum caatingae

Overview

Capsicum caatingae is a wild member of the chilli pepper genus found only in Brazil. Unlike the compact, short-lived plants most people associate with peppers, it may develop into a substantial woody shrub or small tree. Botanists recognise it by the unusual combination of its upright main stem, very dense flower clusters, coloured corollas and small, pungent red berries.

The name comes from the Caatinga, the seasonally dry landscape of northeastern Brazil in which the species occurs. It is an accepted species in Kew's Plants of the World Online and was formally published in 2011.

Native range

Brazil

Plant form

Woody shrub or small tree

Typical height

2–4 m, sometimes taller

Flowers

Purple, white-edged

Ripe fruit

Small, red and pungent

First described

2011

Discovery and naming

Botanists encountered material now assigned to C. caatingae long before it received a scientific name. The type specimen cited in the modern treatment was gathered in June 1980 near Cachoeira, Bahia, in the valley of the Paraguaçu and Jacuípe rivers. A type specimen is the preserved reference to which a scientific species name is permanently attached.

In 2011, Gloria E. Barboza, Maria de Fátima Agra and colleagues published C. caatingae alongside another Caatinga endemic, Capsicum longidentatum, in Systematic Botany. Their work also clarified the identity of C. parvifolium, because specimens of these related wild peppers had previously been mixed up in publications and herbaria.

The specific name caatingae directly acknowledges the Brazilian biome that shapes this plant's distribution. It is not a horticultural cultivar or an intentionally bred cross; it is a naturally occurring wild species.

Plant and foliage

The species commonly grows as an erect shrub or small tree around 2–4 metres high, with some specimens reaching approximately six metres. The main stem continues growing vertically and becomes woody, often thicker at the base than is typical of cultivated chillies. Older stems have grey or brown bark, while the younger growth is more angular and may carry fine hairs.

Leaves are generally arranged in unequal pairs, a pattern seen in several wild Capsicum. The larger leaves are usually oval to elliptical and may reach 11.5 cm or more in length; the accompanying smaller leaf is noticeably reduced. Their surfaces can be nearly smooth or lightly hairy, especially along the veins. The branches are comparatively slender and can become spreading or scrambling.

These features make the plant recognisably different in habit from the familiar cultivated C. annuum, even before it flowers.

Flowers and fruit

The flowers are the most striking feature of C. caatingae. They are carried in crowded groups, typically with several blossoms at a node and occasionally 20 or more. The five-pointed, star-shaped corolla has deep violet or purple colouring, a conspicuous white margin and a greenish-yellow to pale centre. Young buds and their stalks may also show strong purple pigmentation.

As the flowers develop into fruit, their stalks hang down and may be green or deep purple. A narrow ring-like constriction appears where each fruit stalk joins the base of the calyx. This small structural feature is useful to botanists when telling wild pepper species apart.

The berries are small, rounded and red at maturity, with pale yellow seeds. The botanical monograph describes them as pungent, although it does not establish a standard Scoville rating. Their small size and striking colour distinguish them from the large, variable fruits developed through domestication in familiar chilli varieties.

Habitat and distribution

C. caatingae is endemic to Brazil and has been recorded in Alagoas, Bahia, Pernambuco, Sergipe and northern Minas Gerais. Its known habitats include the edges of dry deciduous woodland, more open thorny vegetation, savannah-like sites and rocky slopes. Records span approximately 100–950 metres above sea level.

The Caatinga experiences a marked dry season. Many neighbouring trees and shrubs lose their leaves during dry periods, and the landscape includes exposed granite and gneiss outcrops. Despite its ability to live in these settings, C. caatingae is also sometimes recorded in disturbed areas and, less often, degraded moist forests.

Field records cited in the 2022 monograph show flowering from December to August and fruiting from February to October. These are observed collection periods rather than a guarantee of identical timing in cultivation. A plant raised from Bahia seed was reported to have survived for more than thirty years at the Federal University of Viçosa, showing how long-lived this species can be under favourable conditions.

Relationship to other wild peppers

Capsicum caatingae belongs to a group of wild Brazilian peppers referred to as the Caatinga clade. It is especially close in appearance to C. parvifolium and occurs in some of the same regions as C. longidentatum. Careful study of its flowers, fruit and seeds was essential to establishing it as a separate species.

How botanists distinguish them

C. caatingae can carry 20 or more flowers at one node and produces red berries with pale yellow seeds. By contrast, C. parvifolium generally has fewer flowers at a node and produces translucent greenish-golden fruit with dark seeds. C. longidentatum is usually a smaller shrub, bears more conspicuous calyx appendages and has largely white flowers with greenish-yellow markings.

The recorded chromosome number for C. caatingae is 2n = 24. Earlier chromosome studies sometimes used the name C. parvifolium for material subsequently assigned to this species, another reason the 2011 taxonomic revision was important.

Conservation and local names

The 2022 monograph gave Capsicum caatingae a preliminary Least Concern assessment, reflecting the number and spread of documented locations. This is an assessment published by the researchers, not a claim that a separate IUCN Red List listing has been verified.

Its specialist connection to the Caatinga still matters. The authors describe pressure on the biome from firewood extraction, heavy grazing and the conversion of native vegetation to pasture and farmland. Protecting habitats and maintaining botanical collections therefore remains important for this species and its wild relatives.

Recorded Brazilian vernacular names include pimenta-brava in Bahia, caraibera and semente-de-macaco in Alagoas, and murta in Sergipe. The monograph documents these names but does not report established culinary uses for the species.