Oleanders, commonly called the dogbane family, are a family of angiosperm that consists of herbs, shrubs, trees and lianas.The family numbers around 1,500 species divided in 424 genera. Many of the tree species in the family are characteristic of the tropical rain forests, yet most are distributed in the tropics and subtropics as well.In the moderate climate regions there are numerous herbs and herbaceous plants pertaining to the Dogbane family.
The leaves are simple,usually opposite and decussate or whorled.The flowers are aggregatedin cymose or racemoseinflorescences (rarely fasciculate or solitary).The calyx is five-lobed united into a tube at the base. Inflorescences are terminal or axillary. The stamens number 4-5. Theovary is usually superior. The fruit consists of a drupe, berry-like, a capsule or a follicle.
Some of the widest spread species of the family are: Nerium oleander L.-rosebay, oleander Олеандър; Periploca graeca L., dogbane; Vinca herbacea Waldst. & Kit.- vinpocetin, periwinkle (Vinca) etc.