HippocastanaceaeHorse-chestnut family

  - Large trees.
  - Leaves opposite, compound with 3 leaflets.
  - Stipules absent.
  - Flowers bilaterally symmetric with 5 free petals.
  - Large, leathery fruit, with one or two large seeds.

Diagnosis: Trees, without stipules, large opposite leaves with 3 leaflets, entire and glabrous.

Local distribution: One species on high cloud forest ridges, the other on both slopes at about 700 to 1400 m.

Similar families
Bignoniaceae: leaves opposite, but with more than three leaflets.
Rutaceae: a few species have opposite 3-foliolate leaves, but they are small trees with translucent yellow dots and aromatic odor.

Diversity: Total: 2 genera, 2 species. Trees: 1 genus, 2 species.

Comments: Both species can reach a large diameter. Billia is the only genus in Costa Rica.

Credits: Images and text copyright 2000-2007, William A. Haber, http://efg.cs.umb.edu/