Subject: Large horned caterpillar
Geographic location of the bug: Kealakekua, HI 1650 feet
Time: 05:48 PM EDT
Your letter to the bugman: Cat brought this in today and we rescued it. Pinked spotted hawkmoth?
How you want your letter signed: Sue
While this is not a Pink Spotted Hawkmoth Caterpillar, it is a hornworm from a different species in the same family. We believe this is a pre-pupal Privet Hawkmoth Caterpillar,
Psilogramma menephron, which is pictured on Sphingidae of the Americas where it states: “This caterpillar is green with a strong curved horn on its tail pointing backwards, and a series of diagonal white stripes on its sides. The coloration of the Caterpillar looks very striking, but when the Caterpillar is on a Privet bush, the spacing of the stripes is about the same as that of the leaves, and the Caterpillar becomes very hard to see. This use of colour to hide is a form of camouflage called disruptive coloration. The Caterpillar is most easily located by observing the black fecal pellets under the bush where it is feeding. When disturbed, the Caterpillar lifts the front of its body, and bends its head underneath, exposing a series of white warts on its shoulders. It grows to a length of about 90–110mm and has both green and brown forms.”
Thank you so much! With your info I was able to find out more and wish now I’d killed it as is a newer species here in Hawaii .
Update: January 28, 2019
Daniel, just found another that could be our caterpillar and is an endangered native. I’ve seen a sphinx moth similar to this a few times so hopefully this is it. https://dlnr.hawaii.gov/