Oleander aphids

Description:

Yellow-orange with black cornicles, legs and antennae. Alates have pigmented thorax. Common on milkweed, oleander. (information from BugGuide)

Notes:

Native to the Mediterranean, now cosmopolitan. NA populations are parthenogenetic. Like the Monarch and related butterflies, these aphids pick up deadly cardiac glucosides from the host plant and deposit them in their bodies. The noxious chemicals also become part of their cornicle secretions (exuded from the tubes on the rear end). Their bright orange color serves as a warning to predators- at best they taste awful, at worst they can kill. Larvae of lacewings and lady beetles that feed on Aphis nerii may have developmental problems during pupation, and either emerge with deformities (especially of the wings), or fail to emerge at all. (information from BugGuide)