Dragon fruit is a cactus. It belongs to the family Cactaceae, making it a direct relative of prickly pear, the saguaro, and dozens of other spiny, drought-adapted plants found across the Americas. That surprises many people who encounter the bright pink fruit in a grocery store without realizing it grows on a sprawling, vine-like cactus native to Central America.
Dragon Fruit’s Place in the Cactus Family
The plant that produces dragon fruit was long classified in the genus Hylocereus, a group of climbing cacti with thick, triangular stems. More recent genetic and anatomical work showed that Hylocereus isn’t actually a separate lineage from the closely related genus Selenicereus, so scientists folded the two together. The dragon fruit you’re most likely to find at a store, the white-fleshed variety with pink skin, is now formally called Selenicereus undatus. The red-fleshed variety is Selenicereus monacanthus.
Both species are native to southern Mexico and the Pacific coasts of Guatemala, Costa Rica, and El Salvador. They evolved to thrive in dry tropical climates with moderate rain, clinging to trees and rock faces with aerial roots, much like an orchid or a philodendron would. That climbing habit sets them apart from the squat, ground-hugging cacti most people picture.
Its Closest Relative: Yellow Dragon Fruit
The yellow-skinned dragon fruit sold at specialty markets is the closest well-known relative. Formally called Selenicereus megalanthus, it has spiny skin rather than the smooth, leafy bracts of the pink varieties. Its taxonomy has bounced around for decades. Early botanists noticed its stems looked like Hylocereus while its spiny fruits looked like Selenicereus, so they placed it in its own genus, Mediocactus, to signal its in-between nature.
Genetic studies eventually clarified the picture. Yellow dragon fruit is a tetraploid, meaning it carries four sets of chromosomes instead of the usual two. Researchers believe it arose from a natural cross between two closely related diploid species. Its genome composition is most similar to Selenicereus ocamponis and Selenicereus grandiflorus (the famous “queen of the night” cactus). Breeding experiments found that the red-fleshed dragon fruit crosses most successfully with the yellow variety, suggesting a particularly close genetic relationship between those two.
Other Edible Cactus Relatives
Because dragon fruit sits within the enormous cactus family, it has a wide web of fruit-bearing cousins. Here are the ones you’re most likely to encounter:
- Prickly pear (Opuntia ficus-indica): The best-known edible cactus fruit worldwide. Called “tuna” in Spanish, it has a sweet taste sometimes compared to watermelon. Several other Opuntia species, including O. streptacantha and O. cardona, are cultivated for their fruit as well. Prickly pear and dragon fruit are in the same family but belong to different genera, so they’re relatives in the way cousins are rather than siblings.
- Peruvian apple cactus (Cereus repandus): A tall, columnar cactus that produces an apple-sized, berry-like fruit. It grows commercially in parts of South America and is sometimes called “cardon lefaria.”
- Koubo (Cereus peruvianus): Another columnar cactus grown commercially for its edible fruit, which is similar in size and texture to the Peruvian apple cactus.
- Saguaro (Carnegiea gigantea): The iconic giant cactus of the Sonoran Desert produces red fruit that Indigenous peoples of the region have harvested for centuries. The fruit is considered excellent quality.
- Garambullo (Myrtillocactus geometrizans): Produces small, bluish berries sold in Mexican markets. They look and function more like blueberries than like the large fruits of dragon fruit or prickly pear.
- Pitaya of Stenocereus: This is where naming gets confusing. In Central America, the fruits of Stenocereus cacti are sometimes called “pitaya,” while dragon fruit goes by “pitahaya.” Both are cactus fruits, but they come from different genera and look quite different. Stenocereus species tend to be columnar desert cacti, not climbing vines.
Why Dragon Fruit Doesn’t Look Like a Typical Cactus
Most people associate cacti with barrel shapes, sharp spines, and bone-dry desert landscapes. Dragon fruit breaks nearly every one of those expectations. Its stems are long, flexible, and climb up supports. Its spines are small or absent on mature growth. And the fruit itself is covered in fleshy, leaf-like bracts (the green or pink “scales” on the outside) rather than the tough spines you’d find on a prickly pear fruit.
These differences reflect the plant’s habitat. Dragon fruit cacti evolved in tropical forests, not open desert. They grow in the understory or along tree trunks where rainfall is moderate and humidity is higher than in a classic cactus environment. The climbing growth habit lets them reach sunlight through the canopy, and their reduced spines make sense in a setting where water theft by animals is less of a threat than in the desert. Despite these adaptations, the plant retains classic cactus traits at the cellular level: water-storing tissue, a specialized form of photosynthesis that conserves moisture, and flowers that open at night to attract bat and moth pollinators.
How the “Pitaya” and “Pitahaya” Names Overlap
The naming confusion around dragon fruit and its relatives trips up even experienced growers. In much of Central and South America, “pitahaya” refers specifically to the climbing cactus fruits of Selenicereus, the dragon fruits most of us recognize. “Pitaya” is used more broadly for cactus fruits from columnar species like Stenocereus. But the terms are used interchangeably in many regions and almost all English-language marketing.
All pitaya-type fruits fall into four main genera within the cactus family: Stenocereus, Cereus, Selenicereus, and the now-merged Hylocereus. When you see “dragon fruit” at a store, it’s almost always Selenicereus undatus (white flesh) or Selenicereus monacanthus (red flesh). Everything else tends to stay in regional markets or specialty shops.