By Ethan Harry, Cecilia Zumajo-Cardona
Oct 27 2025
Clusia venusta, a species of the Clusiaceae family, is native to the forests of Ecuador and parts of northern South America. Known for its rose colored flowers, Clusia venusta grows primarily as a small shrub, at elevations between 650 to 1,200 meters above sea level. These environments are known for humid conditions and moderate temperatures, ranging between 16°C to 22°C (60–72°F). The species is commonly found in the cloud forests near Santo Domingo de los Tsáchilas, Ecuador.
The genus Clusia is notable for its versatility. Many species can grow both epiphytically and terrestrially, and Clusia venusta follows this pattern. Its thick, leathery leaves reduce water loss, which helps it survive dry areas and wet forests.
Pollen and Pollination
The pollen of Clusia venusta is tricolporate, meaning it has three furrows and accompanying pores. This pollen morphology is typical for eudicots and is central in the plant’s specialized pollination system. Clusia venusta gets pollinated by bees, specifically oil-collecting bees like Centris or Trigona. Rather than offering nectar, Clusia flowers produce floral oils, secreted from glands called elaiophores. These oils are harvested by female bees and used to line their nests or feed their larvae. In the process, bees brush against the anthers and carry pollen to other flowers. Clusia venusta grows in dense populations, likely due to this close plant–pollinator relationship.
Fertilization
Clusia venusta fertilization begins after pollination, when pollen is transferred to the flower’s sticky stigma. From the time the pollen grain adheres to the stigma to when it reaches the ovary to fertilize the ovules, around 1–2 days have passed. Once the pollen tube reaches the ovule inside the ovary, it releases two sperm cells. Clusia venusta, undergoes double fertilization. One sperm fertilizes the egg cell, forming a zygote, which develops into the plant embryo. The second sperm fuses with two polar nuclei to form the endosperm, which will nourish the embryo as the seed matures. After successful fertilization, the ovary develops into a woody capsule fruit, and within that the ovule transforms into a seed. Over the next few months, the fruit matures, dries out, and eventually splits open to release seeds into the environment.
View slides of Clusia venusta morphology from the Maguire slide collection, held at the Pfizer lab.
Overall, Clusia venusta is one of the most fascinating tropical plants, from its unique oil-based offerings to its fruiting cycle that adapted to the highlands of South America. Its ability to thrive both epiphytically and terrestrially, makes it not only a botanical marvel but also a vital part of its native cloud forest ecosystem.
