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I found this bug on a Hosta leaf. What in the world is it? Alice, Old Lyme


What you have is a saddleback caterpillar, Acharia stimulea. The caterpillar is the larva of a species of slug moth native to eastern United States and it is found from Massachusetts to Florida.

Even though they are beautiful caterpillars, they are covered with strong, hollow spines or hairs that are connected to poison glands beneath their skin that are loaded with venom. Saddleback caterpillars are the second most venomous caterpillar in North America and not to be taken lightly. If the spines touch you, you will experience intense pain (worse than a bee sting) and possibly a host of other reactions such as swelling, rash, nausea and migraines. If you are allergic to bee stings, contact your physician immediately. Try to get the spines out of your skin right away to minimize the venom spread - sometimes adhesive tape can help get them out. Also, be aware the spines can fall off the caterpillar and get on surrounding objects like chairs and tablecloths so be careful to clean up around where they've been. The spines easily penetrate garden gloves and long pants, so be very observant when working in your garden!

In this area, each female saddleback caterpillar moth lays 30-50 eggs in June and July and after about ten days the caterpillars hatch. It takes about 4 months for them to reach full size, which is why you might notice them best in the fall. You can find these caterpillars on virtually any tree or plant.

Know what saddlebacks look like and look but don't touch!

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About Linda Lillie

Linda K. Lillie is the President of Sprigs & Twigs, Inc, the premier landscape design and maintenance, tree care, lawn care, stonework, and carpentry service provider in southeastern Connecticut since 1997. She is a graduate of Connecticut College in Botany, a Connecticut Master Gardener and a national award winning landscape designer for her landscape design and landscape installation work.


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