#exaerete

Orchid Bees (tribe Euglossini, family Apidae)

Manu Biological Station, Madre de Dios, Peru

One of my favorite insect encounters at Manu was with orchid bees! The volunteer coordinator, who is also an entomologist, showed me their method for attracting and surveying them.

They pin squares of cardboard to a tree, and dab on scents (which are usually essential oils or extracts). The male bees show up and "gather the scents" which helps them to attract females (so its win-win for the bees and the entomologists).

Here we see 4 species of orchid bee:

Euglossa analis (shiny blue/purple)

Euglossa sp. (smaller shiny green)

Knob-fronted Cuckoo-Orchid Bee, Exaerete frontalis (large black-winged shiny green)

Eulaema sp. (Black front, yellow/black/red abdomen)

Orchid bee

Giant Metallic Orchid Bee (Exaerete frontalis)

Exaerete bees belong to a tribe of bees known as the Euglossini (Orchid Bees). The Exaerete are, without a doubt, the most spectacular of the Neotropical bees. They are characterized by their large size, metallic green coloration and very long tongues, which they use to extract nectar from flowers with long corollas (particularly orchids) and by their cleptoparasitic habits. There are five genera of Euglossini bees and while three of those genera (Euglossa, Eulaema, and Eufriesea) collect pollen and construct nests, the other two genera (Exaerete and Aglae) have evolved as cleptoparasites of Eulaema and Eufriesea. These cleptoparasites act as cuckoos, destroying the eggs of their preferred host and replacing them with their own eggs. Exaerete (pictured) is a genus comprised of 6 species while Aglae is a genus that contains only one species: Aglae caerulae. Females search out the nests of their preferred host and then kill the host’s eggs (and possibly first instar larvae as well). There is also evidence that the developing cleptoparasitic larvae are capable of killing the eggs and young larvae of other cleptoparasites, should another cleptoparasitic female try and use the nest. Bees in the genus Exaerete have a broad geographic range and are found from Mexico to northern Argentina. The specimen pictured was collected in Peru.