The pequi tree grows up to 10 m (30 ft) tall. It is common in central Brazilian cerrado habitat from southern Pará to Paraná and northern Paraguay. Its leaves are large, tough, hairy and palmate, with three leaflets each. Unlike most other cerrado trees, it bears flowers in the dry winter months, approximately July to September. The yellowish-white flowers are hermaphroditic and bear many stamens; they somewhat resemble a huge pale St John's Wort flower (a distant relative among the Malpighiales). There are often two dozen or more flowers per inflorescence.
Pollination is mainly by bats, and as usual in such cases the flowers do not have a pleasant smell but produce copious thin nectar. Flowers open in the evening and produce nectar throughout the night, ceasing in the early morning. As it seems, each night's last nectar, produced around dawn, is richer in sugars than that produced in the night, though it is much less in quantity already. Moths, nocturnal wasps and ants also visit the flowers at night; the former two might also do some pollinating but they are not known to be of major importance. During the day, the flowers are visited by bees and wasps which feed on remaining pollen. From dusk to the cessation of nectar production, hummingbirds may visit the flowers. While most of them only do this opportunistically, some species – e.g. the Fork-tailed Woodnymph (Thalurania furcata) and in particular the Glittering-throated Emerald (Amazilia fimbriata) – appear to visit pequi tree flowers on a regular base. More significantly, visits by small "tanagers" of the Thraupidae and Cardinalidae around dusk are noted. In particular species like the Guira Tanager (Hemithraupis guira), White-lined Tanager (Tachyphonus rufus) and the Palm (Thraupis palmarum) and Sayaca Tanagers (T. sayaca) seem to be quite fond of pequi flower nectar and spend considerable time feeding on it when available. But even Curl-crested Jays (Cyanocorax cristatellus) have been observed to hang about flowering pequi trees at daybreak, though perhaps not just for the nectar, considering many insects attracted by it earlier would still be around on the tree. As the stigmata dry out at daybreak, it is not clear whether birds, particularly "tanagers", play a role in pollination also or are merely making use of an easy early-morning snack, particularly considering that during the flowering season of C. brasiliense, little such food is available.
Fruits start off dark purple, turning olive green and finally buffy green as they ripen, taking about 5–6 months. Ripe fruits are about the size of an orange. They resemble a mangosteen (another distantly related member of the Malpighiales) in having a few (usually 1-4) segments of pulpy pericarp inside the skin, yellow and with a typical strong taste and smell mixing sweet, fruity and cheesy aromas; this is derived mainly from volatile ethyl esters. Embedded in the mesocarp is a light-colored seed enclosed in a blackish shell covered with thin and tough woody spines, though spineless individuals exist in the wild. Both the mesocarp and the seed are edible for humans as well as many animals, including usually carnivorous species like the Yellow-headed Caracara (Milvago chimachima).
Read more about Caryocar Brasiliense: Use By Humans and Status