2. BACKGROUND ^ * Greek for “away from dog” -> in reference to some taxa used as dog poison ^ 411 genera; 4650 species ^ Worldwide distribution, mostly present in tropical regions. ^ Economic importance: used as cultivated ornamentals Nerium(oleander), Plumeria, Stapelia, and Vinca(periwinkle) medicinal uses
3. APOCYNACEAE ^ Belongs to the order Gentianales ^ often treated as two families, a) Apocynaceae (Dogbane family) b) Asclepiadaceae (Milkweed family) ^ *the latter now usually classified as subfamily
4. CHARACTERISTICS ^ Plant habit -> lianas, trees, shrubs, or herbs ^ Stems -> succulent in some ^ Leaves -> simple, undivided, sometimes reduced, opposite, whorled, or rarely spiral, and is usually exstipulate ^ Inflorescence -> either a cyme, raceme, or of solitary flowers
5. CHARACTERISTICS ^ Gynoecium -> syncarpous, often only apically (with ovaries distinct), with a superior or a rarely half inferiorovary ^ Ovules -> anatropous, unitegmic ^ Stigma(s) -> capitate, a single, broad fusion product in Asclepiadoids ^ K(5) C (5) A 5 or (5) G(2) [(-8)], superior, rarely half-inferior
6. CHARACTERISTICS ^ Placentation -> apical and pendulous or marginal ^ Nectaries-> sometimes with 5 nectar glands or a disk at ovary base ^ Fruit -> variable and can be a berry, drupe, or follicle ^ Seeds -> endospermous