Note: This family has recently been merged into the dogbane family (Apocynaceae).
Heartleaf Milkweed, Purple Milkweed: Asclepias cordifolia (Synonym: Gomphocarpus cordifolius)
Mexican Whorled Milkweed, Narrowleaf Milkweed, Narrow-leaf Milkweed: Asclepias fasicularis (Synonym: Asclepias mexicana)
Greek Milkweed, Showy Milkweed: Asclepias speciosa (Synonym: Asclepias giffordii)