Capsicum mirabile

Overview

Capsicum mirabile is a wild Brazilian pepper endemic to the eastern and south-eastern parts of the country. It belongs to the nightshade family, Solanaceae, and occurs in humid, mountainous parts of the Atlantic Forest, rather than in fields of cultivated chilli peppers. The species has a branching, almost zig-zag form; thin, unequal paired leaves; patterned flowers; and small round fruit.

The flowers are unusually colourful for a wild pepper. Each has a purple to reddish-brown pattern, a white rim and a yellowish-green centre, though the amount of purple can differ greatly between individual plants. The berries ripen from green to greenish-golden yellow. They are described as pungent in the 2022 monograph, while broader research on the Atlantic Forest group characterises their mature fruit as only weakly pungent. The species is not known as a commercially grown chilli.

A distinguishing feature is its calyx, the little cup under each flower and berry. Five short projections extend from the edge. The flower stalk bends sharply at an angle when in bloom, and the ripe fruit hangs from a longer curved stalk. These details are important because several other Brazilian wild peppers produce very similar small yellow berries.

Scientific name

Capsicum mirabile Sendtn.

Family

Solanaceae

Native country

Brazil

States recorded

BA, ES, MG, RJ & SP

Growth habit

Shrub; usually 1.2–2.5 m

Early specimen

1823, Rio de Janeiro region

First description

1846, Flora Brasiliensis

Flowers

Purple, white & yellow-green

Mature berries

Golden-yellow, 7–9 mm

Pungency

Pungent; generally slight

Chromosomes

2n = 26

Elevation

800–1,900 m

Local name

Pimenta do sapo

Conservation

Preliminary Least Concern (2022)

Discovery & naming

The history of Capsicum mirabile goes back to early nineteenth-century botanical exploration of Brazil. The original scientific description drew on specimens associated with Carl Friedrich Philipp von Martius and Ludwig von Karwinski, collected in forests around the areas then known as the provinces of Rio de Janeiro and São Paulo, and in wet, rocky habitat in Minas Gerais. One surviving Karwinski specimen from near Rio de Janeiro is dated 1823; it is among the earliest clearly dated botanical records connected to the species.

Otto Sendtner published the species in 1846 as part of Flora Brasiliensis, a major botanical project organised by Martius. The plant was therefore described directly in Capsicum; there was no later transfer from another genus. Its Latin epithet, mirabile, means remarkable or wonderful, an apt description for a pepper whose patterned flowers look so different from familiar garden chillies. That translation should not be mistaken for a documented explanation of Sendtner's personal choice of name.

The author abbreviation is not completely uniform across modern botanical references. Kew and the 2011 naming study use C. mirabile Sendtn.; the 2022 monograph prints Mart., while USDA GRIN gives Mart. ex Sendtn. All refer to the accepted species first published in Flora Brasiliensis in 1846. This page uses Kew's author form, Sendtn., for consistency.

An important event happened in 2011. Botanist Gloria E. Barboza reviewed the original material, including three historical specimens, and selected a well-preserved Martius specimen in Munich as the lectotype: the physical reference that fixes exactly which plant the scientific name represents. The historical Karwinski collection matched the species, but the Martius specimen contained more complete identifying features.

Synonyms & a complicated identity

Capsicum mirabile has been a difficult plant for botanists to pin down. Historical herbarium specimens varied in their hairiness, shape of leaves, length of calyx projections and especially the purple markings of the flowers. Some collections were assigned to the wrong species because different populations did not always look identical.

In 1846, the name Capsicum mirabile var. grandiflorum was also published. It is currently treated as a synonym of C. mirabile rather than a separate accepted variety. The original material associated with that name includes a Sellow specimen that was later destroyed, one reminder of how fragile the historical record can be.

In 1969, Armando T. Hunziker described a supposed separate wild pepper called Capsicum buforum, based on material from near Campos do Jordão, São Paulo, collected in December 1967 at approximately 1,400 metres elevation. Modern research places it within the variation of C. mirabile. The 2022 revision chose a specimen held at Córdoba, Argentina, as the lectotype of the name C. buforum.

There was confusion in the opposite direction as well. A 1966 flora included plants from the Brazilian state of Santa Catarina under C. mirabile; later work showed they belonged to other plants, including C. recurvatum and species of Athenaea. The modern range of true C. mirabile does not extend into Santa Catarina in the 2022 account.

Hunziker sometimes labelled plants informally as C. mirabile var. without publishing a clear variety name, reflecting the complexity he saw in these collections. Later identification keys, herbarium study and DNA research were needed to make its boundaries clearer.

Plant & foliage

Most C. mirabile plants are erect shrubs or subshrubs around 1.2–2.5 metres high, although individuals from about 70 cm to 3 metres are recorded. An occasional plant can take on the appearance of a small tree. Mature stems may reach about 2.5–4 cm thick at the base. The branches fork repeatedly, often making a conspicuous zig-zag pattern through the surrounding vegetation.

New stems are green, angled and relatively fragile. Young shoots may carry fine, short, whitish hairs, but the species becomes nearly hairless as its tissues mature. Branch joints can be green or purple, while older bark turns dark brown. The lack of visible lenticels on older stems is one of the details recorded in the modern description.

At many branch points the leaves appear in unequal pairs. The larger leaf is commonly 5–13.5 cm long, mostly 1.3–3 cm wide, sometimes broader. It is elliptic, narrowly elliptic or occasionally egg-shaped, with a long pointed tip, a slightly uneven base and smooth edges. Its leaf stalk is about 0.7–2.5 cm long. The smaller companion is often only 2–4 cm long and 0.9–1.7 cm wide.

The foliage is green above and typically a lighter green below. Individual leaves range from rather thin and papery to firmer in texture. Fine hairs tend to be sparse, occurring especially along veins and margins on younger leaves. This limited hairiness is important when separating the species from its notably hairy Brazilian relatives.

Flowers, unusual colour & calyx

The flowers grow at the leaf joints, most often in groups of two to five, occasionally as many as seven. Flower stalks are about 16–25 mm long, sometimes slightly shorter. As a bud opens, the stalk develops a sharp bend known as a geniculation, a characteristic often used when identifying wild Atlantic Forest peppers.

Flower buds are rounded and inflated, commonly greenish-purple or dark purple. Fully opened flowers are star-shaped, about 10–13 mm across, normally with five spreading lobes. Their colour is striking: a whitish border, a yellowish-green centre and a variable wash or pattern of purple to reddish-brown between them. The coloured markings may cover most of the inner petal lobes, form smaller individual spots or be so pale that they are nearly absent.

The 2022 authors specifically note that the original 1846 description did not mention the purple flower spots. This likely contributed to later misidentifications. Modern field photographs show that the same species can appear to have quite different flowers, particularly when comparing plants from different localities and collections.

The green, cup-shaped calyx behind each flower is small, around 1.5–2.2 mm long, with five projections that are usually about 0.5–1.5 mm long, occasionally reaching 3 mm. These may stand upright or spread outward. Their length changes across populations, especially between some São Paulo and Minas Gerais collections and those from Rio de Janeiro or Espírito Santo.

Each flower has five stamens. The anthers begin yellowish and can become reddish-brown or grey-purple after releasing pollen. A ring of tiny glandular hairs lines the inside of the corolla tube. Beneath the style, the small ovary is connected to a nectar-producing structure, as in other members of Capsicum.

Fruit, pungency & black seeds

The fruits are small, round berries measuring only 7–9 mm across. They begin green and mature to a greenish-golden yellow colour, rather than the scarlet red of many familiar bird peppers. The berry wall is relatively thin and translucent. At maturity, the fruit may detach from the stalk.

The 2022 botanical monograph describes the ripe berries as pungent. Earlier evolutionary work characterises the ripe fruit of the Atlantic Forest group as scarcely pungent. These descriptions are compatible with a pepper that can have heat, but much less than the strongly pungent cultivated chillies. There is no reliably established species-wide Scoville figure in the principal botanical descriptions, so a precise heat value should not be assigned to it.

When fruit develops, the stalk becomes longer, about 20–32 mm, and curves downward. The green calyx persists under the berry as a small disc. Its five slender projections may spread around the fruit, reaching about 0.7–3.5 mm in length. The combination of round golden berries, a bent hanging stalk and five calyx teeth is a useful identification clue.

Each berry generally holds three to eight seeds, although counts as low as two and as high as ten are documented. They are comparatively large for such a small fruit: approximately 2.5–3.2 mm long, curved and brownish-black to black. Under a microscope, the seed coat has a net-like surface with tiny raised projections along its margins. This differs noticeably from the pale, relatively smooth seeds of many domesticated peppers.

The 2022 anatomical study also recorded enlarged cells in the inner fruit tissues and a textured inner fruit wall. These small structural details help botanists compare Capsicum species independently of their visible fruit colour.

Native range, habitat & flowering

Capsicum mirabile is endemic to Brazil. The detailed 2022 treatment records it from Bahia, Espírito Santo, Minas Gerais, Rio de Janeiro and São Paulo, spanning part of eastern and south-eastern Brazil. This distribution covers several mountain ranges and forest blocks, rather than a single tiny locality.

Its principal home is the humid Atlantic Forest, or Mata Atlântica. The species occurs inside forest, in the understorey and at woodland edges. It is especially associated with dense, moist montane forest, known in Brazilian vegetation classifications as Floresta Ombrófila Densa Montana. Recorded elevations are usually between 800 and 1,900 metres above sea level.

In such mountain forests, the vegetation is layered and the air often remains comparatively humid. The shrub can occupy shaded areas beneath taller trees as well as more exposed margins. Its natural habitat is very different from the hot, exposed agricultural fields commonly used for cultivated chilli production.

Field and herbarium observations place flowering mainly from November to April and fruiting from December to May. Those are observations from Brazil, not a fixed flowering calendar for plants cultivated in other climates.

The São Paulo common name pimenta do sapo translates literally as toad pepper. The 2022 monograph documents this local name from Hunziker's collections. Its scientific name, local name and delicately patterned flowers have all attracted interest among collectors of wild peppers, even though the species has no established commercial crop history.

Genetics & evolutionary history

Chromosome studies of C. mirabile record 2n = 26, or thirteen pairs of chromosomes. Studies have also recorded the haploid number n = 13. Some of the research material was previously listed under Capsicum buforum or an unnamed Capsicum accession, showing how changes in species identification can affect scientific databases.

DNA research places it in the Brazilian Atlantic Forest evolutionary group of wild Capsicum. This includes relatives such as C. villosum, C. schottianum, C. campylopodium, C. carassense, C. friburgense and C. muticum. The group shares a forest-adapted growth habit, frequently patterned flowers and small berries, while its species vary in leaf hairiness, calyx teeth and floral colour.

A landmark 2016 phylogenetic study showed that the Atlantic Forest group with 13 chromosome pairs is not simply part of the Andean group, which also has 13 pairs. Instead, the two groups appear to have acquired this chromosome number independently from ancestors with twelve pairs. Later chromosome-evolution research has further supported independent changes to the number 13.

The species belongs to a separate branch from the familiar domesticated C. annuum, C. chinense and C. frutescens peppers. Studying these Brazilian forest species helps reconstruct the broader evolution of the genus, including changes in flower form, seed coats, fruit heat and chromosome number.

Researchers still describe C. mirabile as morphologically variable, with some relationships among its closest-looking Brazilian neighbours not fully settled. Genetic placement is helpful, but examination of real flowers, leaves and calyces remains essential to correct identification.

How to distinguish it from related species

The most reliable identification uses several characters together: almost hairless zig-zag branches, unequal leaf pairs, purple flower buds, white-edged flowers with a purple pattern, five short calyx teeth and round golden-yellow berries. Looking only at the yellow fruit is not enough because multiple Atlantic Forest species share similar colours.

Compared with Capsicum carassense

These are particularly easy to confuse. C. carassense generally has much narrower, longer-looking leaves, more noticeable hairs, shorter petioles, cream-coloured buds with greenish-purple markings, and larger flowers, about 13–20 mm across. C. mirabile has broader elliptic or ovate leaves, sparse hairs, usually purple buds and flowers mostly 10–13 mm across. Its calyx teeth are typically shorter.

Compared with Capsicum villosum and C. muticum

C. villosum is more densely hairy, including its stems and flower stalks. It also generally has smaller flowers with a larger area of white and greenish-yellow. C. muticum is another conspicuously hairy species, but its most useful distinguishing feature is a calyx without the five clear projections characteristic of C. mirabile.

Compared with Capsicum friburgense

These two can occur together near Caledônia in the Nova Friburgo area of Rio de Janeiro. Both bear small yellowish fruit and dark seeds, but C. friburgense has bell-shaped, mainly lilac or pink flowers. C. mirabile has a more star-shaped flower with a multi-coloured purple, white and yellow-green pattern.

Compared with Capsicum recurvatum

This is the species involved in older Santa Catarina misidentifications. Its flowers are mainly white, and the calyx often has five to ten uneven projections, rather than five approximately equal ones. Geographic range also helps: the modern account does not record true C. mirabile from Santa Catarina.

Conservation

The authors of the 2022 Capsicum monograph gave C. mirabile a preliminary Least Concern (LC) assessment. They calculated an extent of occurrence of about 190,249 km² and an occupied area of about 224 km² from the records available to them. These are two different geographic measurements and should not be interpreted as a total count of its forest habitat.

They noted records in many protected areas, including Itatiaia National Park, Serra dos Órgãos National Park, Serra da Bocaina National Park, Caparaó National Park and the Boracéia Biological Station, among others. The authors considered the species fairly widespread and not especially rare within suitable forest sites.

Nevertheless, Atlantic Forest clearance and fragmentation can isolate populations outside reserves. Remaining connected mountain forests therefore matter for maintaining its long-term genetic diversity and natural distribution. The published Least Concern status is a scientific preliminary assessment, not a claim that this page independently confirmed a formal IUCN Red List entry.

Kew also displays a separate automated extinction-risk prediction for the accepted name, but it explicitly marks that prediction as low-confidence. The direct field- and specimen-based 2022 assessment is the clearer basis for this page's conservation summary.