Every pepper belongs to the genus Capsicum, in the tribe Capsiceae, subfamily Solanoideae, family Solanaceae. Kew's Plants of the World Online currently accepts 43 species in the genus, matching the 2022 monograph by Barboza and colleagues. Five of those 43 carry a domestication history: C. annuum, C. chinense, C. baccatum, C. frutescens and C. pubescens. The other 38 grow wild, mostly in South America. Our full Kew species list names all of them with authorities and native ranges.

Where Capsicum sits in the hierarchy

One caution before the table. The ranks above family come from competing classification systems, and databases mix them. Tracheophyta and the angiosperm groupings follow the modern phylogenetic treatment that Kew and Catalogue of Life use. Magnoliopsida belongs to the older Cronquist scheme that USDA PLANTS still carries. Both point at the same plant. Neither one is an error, and no rank above Solanales changes anything a grower does.

RankNameNote.
DomainEukaryaCells with a nucleus.
KingdomPlantaeMulticellular photosynthetic organisms.
Phylum (division)TracheophytaVascular plants. Kew and Catalogue of Life use this rank name.
ClassMagnoliopsidaCronquist-era name for dicots, retained by USDA PLANTS. Phylogenetic treatments drop it for "eudicots".
OrderSolanalesNightshades, morning glories and relatives.
FamilySolanaceaePeppers, tomatoes, potatoes, eggplant, tobacco, petunia.
SubfamilySolanoideaeThe fleshy-fruited core of the family.
TribeCapsiceaeTwo genera only: Capsicum and its sister genus Lycianthes.
GenusCapsicum L.43 accepted species in Plants of the World Online.
Speciesannuum, chinense, baccatum, frutescens, pubescens, and 38 wild speciesThe epithet stays lowercase and italic, always.

The five domesticated species

Author abbreviations and dates come from the Kew record. Linnaeus described two of the five in Species Plantarum in 1753, more than two centuries before anyone measured a Scoville rating.

SpeciesAuthor and yearNative rangeField marks.
C. annuumL., 1753Southern USA to Brazil and the CaribbeanWhite flowers, one per node, tan seeds. Bells, jalapeños, cayennes, poblanos.
C. frutescensL., 1753Southern Mexico through tropical AmericaGreenish-white flowers, small upright pods. Tabasco types.
C. baccatumL., 1767Colombia to northern Argentina and BrazilYellow or green spots on the corolla. The single most reliable mark in the genus. Aji types.
C. chinenseJacq., 1777Southern Guyana to Suriname and northern BrazilTwo or more flowers per node, a calyx constriction, floral aroma. Habaneros, scotch bonnets, superhots.
C. pubescensRuiz & Pav., 1799Peru to BoliviaPurple flowers, black seeds, hairy leaves. Rocoto and manzano.

What does the species name tell a grower?

More than the cultivar name does. Species identity predicts maturity time, cold tolerance and cross-compatibility, and those three decide how you plan a season. C. chinense germinates slowly, sulks in cool weather and wants 90 to 120 days from transplant. C. annuum moves fastest and covers the widest range of pod shapes of any species. C. pubescens handles cool Andean conditions better than any other domesticated pepper and sets fruit poorly in sustained heat, which is why growers in hot climates fail with rocoto and blame themselves.

The epithet also misleads. C. chinense has no connection to China. Nikolaus von Jacquin named it in the 1770s on a mistaken assumption about its origin, and the plant traces to the Amazon basin. C. annuum means "annual", which the plant is not: it lives for years anywhere that frost stays away.

Can different Capsicum species cross?

Some can, and the pattern follows the genetic lineages rather than convenience. C. annuum, C. chinense and C. frutescens form one closely related complex, and crosses among them succeed routinely enough that commercial superhots carry genes from more than one. C. baccatum sits further out, and crosses with the annuum complex set poorly and produce weak or partly sterile offspring. C. pubescens sits furthest out of all. The Chile Pepper Almanac states flatly that it will not cross with the other domesticated species, and lists C. eximium as compatible with the pubescens group instead. That matters for seed saving: a pubescens plant next to a habanero stays clean, while two annuums twenty feet apart will not.

How binomial nomenclature works

Linnaeus gave every species a two-part Latin name: a capitalized genus followed by a lowercase epithet, both italicized, with the describing author's abbreviation after it. Capsicum annuum L. tells you Linnaeus published the name. Capsicum chinense Jacq. credits Jacquin. When a later botanist moves a species into a different genus, the original author's name goes in parentheses, which is why the wild species list carries entries like Capsicum coccineum (Rusby) Hunz. Cultivar names sit outside this system entirely: 'Carolina Reaper' is a cultivar of C. chinense, in single quotes, not italics. Our page on species, landraces and cultivars draws those lines, and classification systems covers how USDA GRIN and the trade indexes differ from the botanical treatment.

Why the count keeps moving

Barboza's team added several species in the 2010s and 2020s from Brazil, Bolivia and the tropical Andes, and molecular work continues to reshuffle boundaries. The 43 figure holds today. It held at a lower number a decade ago and may not hold in another decade. Anyone citing a round number like "about 30 species" is quoting an older count. Check the Kew list rather than a secondary source, and cite the date you checked.

Sources & Further Reading