Wednesday, July 13, 2016

Carnivorous Butterfly

Carnivorous captive - Kevin Firth
Kevin Firth sent me these photographs of his fearlessly holding a carnivorous harvester butterflyFeniseca tarquinius, that he had found on Rocky Barrens CA north of SpringfieldThis is the only carnivorous butterfly species in North America.

Chilling out with Kevin Firth
Short proboscis - Kevin Firth
Kevin's feat isn't as reckless as it sounds.  The butterfly itself isn't carnivorous but obtains its nutrition by using its short proboscis to sip honeydew from aphids rather than nectar from flowers.  Scale insects and aphids sucking high pressure phloem from plants excrete the sugary fluid out their intestines where it is collected by some species of ants, bees and wasps and sometimes car windows.

Woolly aphid - Mark Bower

The carnivorous behavior occurs earlier in its life cycle.  The females lay their eggs in colonies of woolly aphids and sometimes scale insects.  The caterpillars then eat the aphids, sometimes protecting themselves under a silk mat with a coating of aphid carcasses.  You may recall the woolly aphids from last month's blog.

Caterpillar camouflaged by aphids-Tom Murray CC

Early instar wax covered
Jerry F. Butler

Interesting that an aphid camouflaged by material on its back is devoured by a caterpillar that uses aphids' bodies to cover itself, the insect version of Russian nesting dolls.

The caterpillars share a chemical profile with the aphids, and that, plus their cover of aphid bodies are felt to serve as protection from ants that will farm these aphids like cattle, collecting their honeydew.  Just another example of the complex networks of symbiosis, parasite and prey relationships in nature.

July 20, 2016 update
Kevin raised the caterpillars and now has the pupa.  Congratulations, Dad!

Carnivorous caterpillar- Kevin Firth

Read a more detailed account with photographs at this Florida University site.

F. tarquinius chilling out- Linda Ellis
Want to photograph a butterfly on your finger?  Unless you are lucky enough to have one land on you like Linda Ellis, try chilling it in the refrigerator for a while, then shoot fast before it warms up and flies away.

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