Hag Moth Caterpillar (Phobetron pithecium)
The Hag Moth Caterpillar, also referred to as the Monkey Slug, can be found in Eastern North America and into the Midwest. It's about 1 inch in diameter and is most known for having a very bizarre appearance, like a visual oddity. They are also part of the slug moth caterpillar family, which have sucker's and move just like slugs.
The appearance can vary widely, with many shapes and bright colorations. The caterpillar has 6 hairy appendages, and is cleverly designed to help with camouflaging techniques to avoid predators. When not moving, it could be mistaken for a dead leaf, but when it is moving, it can be mistaken for a tarantula instead!
Although it uses sucker's to move around, the Hag Moth Caterpillar still has itty bitty true legs near its head and under the thorax. Ooh, and its belly is transparent, so you can see their open circulatory system in action!
Now, it is important to note that these guys have spines underneath their small hairs that can be irritating or painful upon contact if you ever come across one. So it is more of a look, do not touch situation.
Despite the extraordinary appearance they have as a caterpillar, they do not metamorphosize into anything just as crazy. The Hag Moth is a mottled brown, super furry, and has tufts of hair that extend from every leg. The males have more of a translucent wing, while the female has light ivory hairs on her legs and is much larger in size. Adult moths are also a lot rarer to find out and about.
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