Dilleniaceae

Hibbertia stellaris

Dilleniaceae is a family of flowering plants, consisting of about 500 species divided among 10 to 14 genera. The family is named after the German botanist Johann Jacob Dillenius, and it is widely distributed in tropical and subtropical regions of the world, with a particular concentration in Australasia and the Indo-Pacific. Members of the Dilleniaceae family are diverse, including trees, shrubs, and rarely herbs, known for their often large and showy flowers.

Characteristics

Plants in the Dilleniaceae family typically have simple, often glossy leaves that are usually alternate, though sometimes opposite. The leaf margins can be entire or toothed. One of the distinctive features of this family is the presence of stipules or stipule-like structures at the base of the leaves in some genera.

The flowers of Dilleniaceae are usually large and conspicuous, with five (rarely four) petals that can be white, yellow, pink, or purple. The flowers are hermaphroditic, containing both male (stamen) and female (pistil) reproductive structures. The stamens are often numerous, and the ovary is superior, with two to many carpels.

Fruits in the Dilleniaceae are typically capsules, berries, or rarely, drupes. The seeds are often surrounded by a fleshy aril, which can be colorful and attractive to animals, aiding in seed dispersal.

Genera

The Dilleniaceae family includes several genera, the most well-known of which include:

• Dillenia – The type genus, which includes species like Dillenia indica, commonly known as the elephant apple.
• Hibbertia – A large genus of shrubs and climbers, notable for its yellow flowers.
• Tetracera – Known for species with climbing habits and often used in traditional medicine.

Distribution and Habitat

Dilleniaceae species are found in a wide range of habitats, from rainforests to dry deciduous forests, and from sea level to mountainous regions. They are primarily distributed in the tropics, with a significant number of species in Australasia, Southeast Asia, and the Pacific Islands. Some species are also found in Africa and the Americas, demonstrating the wide ecological adaptability of the family.

Ecological Role

Members of the Dilleniaceae family play significant roles in their ecosystems. Their flowers are important for pollinators, including bees, birds, and bats, while their fruits are a food source for various animals, contributing to seed dispersal. Some species are used by local communities for timber, medicine, and as ornamental plants.

Conservation

While many species within the Dilleniaceae are not currently considered at risk, habitat destruction and climate change pose threats to their survival, especially for those with limited distributions or specific habitat requirements. Conservation efforts are necessary to ensure the preservation of this diverse plant family.

See Also

• Botany
• Flowering plant
• Pollination
• Seed dispersal