Apocynaceae

Plant Sex: Flowers bisexual.

Flowers: Actinomorphic; in Asclepias-type flower. Petals modified into a CORONA: HOOD & HORN. Filaments, anthers, and style adnate – whole structure referred to as a GYNOSTEGIUM. Pollen in coherent masses called POLLINIA with two anthers connected by TRANSLATOR arms and a GLAND (attaches to pollinator).

Inflorescence: Umbels and cymes.

Fruits: Follicles.

Seeds: With a COMA of long hairs at the tip (wind dispersed).

Habit: Herbs, vines, trees, shrubs. Some succulent members (e.g. Stapelia). Sap often milky (latex).

Leaves: Opposite, alternate, whorled, simple, no stipules.

Pollinial clade

Asclepias

A. curassavica (bloodflower). Flowering plant. Inflorescence. Flower, lateral view, with one corona (hood and horn) removed. Flower, lateral view, partial dissection and L.S.
A. syriaca (common milkweed). Flowering plant. Inflorescence. Flower. Flower with trapped fly. Fruiting plant.
A. tuberosa (butterfly weed). Flowering plant. Flowers.
Some interesting Asclepias species: A. physocarpa, A. crispa, A. incarnata.

Stapelia

S. gigantea (carrion flower). Flowering plant. Close-up view of central part of flower with visiting fly.

Ceropegia

C. woodii (rosary vine). Flowering plant. Flower. Flower L.S. Flower, basal part dissected.

Hoya

H. carnosa (wax plant). Flowering plant.
H. grandiflora. The large waxy flowers are spectacular!

Cynanchum

C. laeve (shallow-wort, bluevine). Flowering plant. Inflorescence with aphids! Flower. Flowers L.S. Fruit.

Calotropis

C. procera (mudar). Habit of plant in flower. Closer view of flowers. Fruiting plant. Fruit opened up.

Non-pollinial clade

Allamanda

A. cathartica (golden trumpet). Flowering shoot.

Apocynum

A. canabinum (dogbane). Fruiting plants.
A. sibiricum (dogbane). Flowering plant.

Catharanthus

C. roseus (Madagascar periwinkle). Flowering plant. Flowers.

Nerium

N. oleander (oleander). Flowering shoot. Flowering shoot with young fruit.

Plumeria

P. rubra (frangipani). Flowering shoot.

Vinca

V. minor (periwinkle). Flowering shoot. Flower face view. Flower L.S.

SIUC / College of Science / Elements of Plant Systematics
URL: http://www.plantbiology.siu.edu/PLB304/Lecture21Solan/Apocynaceae.html
Last updated: 10-Apr-08 / dln