When we were traveling in Turkey, I got a few chances to photograph some of the wildlife, featured in a recent post, but largely unidentified. Thanks to one of my savvy fellow travelers who found an image of one of the creatures on Flickr, I now have a name for the caterpillar I saw. It turns out the species also occurs in the U.S., even in Minnesota, where it was introduced on purpose to control a noxious invasive called leafy spurge. (Below, leafy spurge was one of the earliest plants to emerge last spring near my backyard.)
This little beauty…is the caterpillar of the Spurge Hawk-moth (Hyles euphorbiae), seen in one of its native lands (asian part of Turkey) on one of its natural food sources, perhaps Euphorbia lambii, the Tree Euphorbia. The plant is native to the Canary Islands, but has been introduced everywhere in the world as an ornamental.
In fact these spurge bushes were crawling with caterpillars, and they were doing a fine job of trimming back the green vegetation to bare sticks. Black coloration with white spots and red trim makes the caterpillars really stands out. When streched out, you can see green segments between the black and white.
Typically such eye-catching coloration is a warning to predators that the prey is inedible at the least, or poisonous at the worst. Its host plants, the euphorb species, are toxic, especially the leaves. However, sea gulls have been observed to pluck the caterpillars right off the euphorb bushes growing near the sea shore, so perhaps their toxicity is mild.
The adult moth is quite attractive with well-defined brown patches on the forewings and pink coloration on the hind wings. They are day-flying moths (like other sphinx moths), and exhibit hummingbird-type flight when visiting flowers, hovering near the flower heads and dipping their long coiled proboscis systematically into each flower.
Photo from: http://ukmoths.org.uk/show.php?bf=1986
After mating, females lay clusters of up to 50 eggs on leafy spurge plants, adhering them to the stems with a sticky gum substance. Easy to see why the plants we saw on our hike were covered with maturing caterpillars.
Photo from: http://en.wikipedia.org/wiki/Hyles_euphorbiae
Even if the caterpillars defoliate the spurge, the plants seem to recover quite nicely. Unfortunately, the moth’s introduction has not provided the biological control for leafy spurge that was hoped for.