Subject: Bright red caterpillar
Location: Southern Arizona ( Santa Cruz county)
August 25, 2017 7:58 pm
I have been noticing these bright red caterpillars during my evening walks.
They are on a plant that I have not found on our property, so that may be their host plant
Do you know what is caterpillar is ?
Signature: Len Nowak ( Salero Ranch )
Dear Len,
This is a Pipevine Swallowtail Caterpillar, and according to BugGuide: “Larvae feed on Aristolochia species. These include ‘Pipevine’ or ‘Dutchman’s Pipe’, Aristolochia species (tomentosa, durior, reticulata, californica), as well as Virginia Snakeroot, Aristolochia serpentaria. Larvae presumably take up toxic secondary compounds (including Aristolochic acid) from their hostplant. Both larvae and adults are believed toxic to vertebrate predators, and both have aposematic (warning) coloration.” The adult Pipevine Swallowtail is sometimes called a Blue Swallowtail and it is a gorgeous butterfly.