Coffee Varieties Explained: The Family Tree of Arabica

Almost every arabica tree in the world descends from two lineages that spread out of Yemen centuries ago: Typica and Bourbon. Most of the other names you see on coffee bags — Caturra, Catuai, Pacamara, the Catimors — are mutations of those two, crosses between them, or crosses with a single, accidental hybrid of arabica and robusta found on the island of Timor a century ago.

Once you see the family tree, coffee bags become much easier to read.

Species and varieties

First, the terms. Arabica (Coffea arabica) and robusta (Coffea canephora) are different species, and the arabica and robusta guide covers how they differ. Varieties are distinct populations within a species: Typica and Bourbon are both arabica, in the same way that different apple varieties are all apples. You will also see "varietal" used on coffee bags; strictly it is an adjective, but in coffee it is used loosely as a synonym.

Why arabica's family tree is so narrow

Arabica began in Ethiopia's forests, and Ethiopia still holds a great deal of its genetic diversity — the Ethiopian coffee guide covers this. But very little of that diversity left the region. A 2024 genome study in Nature Genetics estimated that cultivated arabica has an effective population size of only 10,000 to 50,000 individuals, the result of a series of genetic bottlenecks.

In practice, most of the coffee grown outside Ethiopia and Yemen descends from a few plants that travelled along colonial trade routes. That is why the family tree below has so few roots, and why a single disease can threaten so much of it.

The two great lineages

Typica

According to World Coffee Research, Typica was taken from Ethiopia to Yemen in the 15th or 16th century and reached India by about 1700. Between 1696 and 1699 coffee seeds were sent from India's Malabar coast to Java, then a Dutch colony. A single plant reached the botanical garden in Amsterdam in 1706 and was shared with France in 1718. From there, the Dutch introduced coffee to their colonies in Guiana, the French to Martinique in 1723, and the English from Martinique to Jamaica in 1730 — after which Typica spread through the Caribbean and Latin America.

Typica produces good coffee, particularly at high altitude, but it yields very little and is susceptible to the major coffee diseases. Most Latin American plantations grew it until the 1940s; since then it has largely been replaced.

Bourbon

French missionaries carried Bourbon from Yemen to Bourbon Island, today La Réunion, in the early 1700s — which is where its name comes from. It stayed there in relative isolation until the mid-1800s, then spread to Africa and the Americas, reaching Brazil around 1860.

Bourbon gives excellent cup quality at high altitude, with relatively low yields and susceptibility to leaf rust and nematodes. It is still grown in parts of El Salvador, Guatemala, Honduras and Peru, and it is a parent of much of what came after.

Mutations and crosses

The twentieth century was about getting more coffee from each hectare.

• Caturra is a natural mutation of Bourbon, discovered on a farm in Minas Gerais, Brazil, between 1915 and 1918. A single gene makes the plant compact, so trees can be planted closer together and the farm yields more. It has good quality potential but is very susceptible to leaf rust.
• Catuai crosses Mundo Novo with Caturra. It was created by the Instituto Agronômico in Campinas, Brazil, in 1949 and released in 1972. It is smaller still, allowing very dense planting and very high yields — and it is also very susceptible to rust.
• Pacamara crosses Pacas with Maragogipe. Pacas is a Bourbon mutation found in 1949 on the Pacas family farm in El Salvador's Santa Ana region; Maragogipe is a Typica mutation found near the Brazilian city of the same name in 1870, famous for enormous beans. Developed by El Salvador's coffee research institute, Pacamara has very large beans, low yields and exceptional quality potential, and it regularly does well in El Salvador's Cup of Excellence competitions.

These compact, high-yielding varieties transformed Latin American coffee. Their shared weakness was about to matter.

The robusta accident that saved arabica

Arabica and robusta almost never cross naturally. In the 1920s, on the island of Timor, they did: a plant from one arabica and one robusta parent was found growing on a farm. It became known as the Timor Hybrid (Híbrido de Timor).

It inherited something arabica badly needed: resistance to coffee leaf rust, from its robusta side, while keeping cup quality close to arabica. As rust spread across the coffee world, breeders crossed it with compact arabicas:

• Catimor — Caturra × Timor Hybrid.
• Sarchimor — Villa Sarchi, a compact Bourbon mutation from Costa Rica, × Timor Hybrid.

Those two families, and the varieties bred from them, now underpin rust-resistant coffee from Latin America to Asia, including newer releases such as Marsellesa and Obatã. Nearly every modern rust-resistant arabica has the Timor Hybrid somewhere in its ancestry.

The trade-off has been flavour. Early Catimors had a reputation for a flatter, less refined cup, which specialty buyers held against them for years. Breeding has narrowed that gap considerably, and a rust-resistant variety grown at altitude and processed carefully can be excellent.

Africa's own lines

Two of the most celebrated groups grew up separately from the Latin American story:

• Ethiopian landraces — locally adapted populations, plus research selections such as 74110 and 74112, usually sold as "heirloom." See the Ethiopian coffee guide.
• SL28 and SL34 — selected in Kenya in the 1930s and famous for intense, bright coffee, with the resistant Ruiru 11 and Batian bred later. See the Kenyan coffee guide.

And then there is Gesha, an Ethiopian variety that spent decades as an obscure disease-resistance specimen before a Panamanian farm made it the most expensive coffee in the world.

At a glance

Does variety change the taste?

Yes, though less predictably than wine grapes. Variety sets a coffee's potential — its sweetness, acidity, aromatic intensity — and some varieties have a higher ceiling than others. But altitude, soil, farming, harvesting, processing and roasting decide how much of that potential arrives in your cup. The same variety can taste quite different from two farms a valley apart.

Read the variety on a bag as one clue among several. It is most useful when combined with the region, the altitude and the processing method — and most fun when you taste two coffees that differ only in variety, side by side.