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Black Wooly Bear

Black Wooly Bear
Puyallup, Pierce County, Washington, USA
September 7, 2009
We were down at the frog pond tonight, and spent most of the time gingerly stepping around two things; banana slugs & wooly bears. We really would've squished something with every step if we weren't careful. Obviously with that many wooly bears I'm assuming this is one... just an all black one.

Moved from Arctiina.

Moved from Arctiini.


Moved from Tiger Moths.

I have doubts on this
I've never seen the adult in my area.

Move again to taste.
Move again to where you like it. I was doing a bulk move by request. I don't know anything about these guys.

Platarctia parthenos larva
They can become common in the fall. I found one that died of an overdose of conifer resin...

I totally agree.
This looks like Platarctia parthenos. I don't think this is Pyrrharctia isabella.

on second thought
Platarctia parthenos larvae do not have setae this bristly. Their setae are longer, more like Arctia caja.

My experience
All the Platarctia parthenos larvae i have seen so far look exactly like this one. Mind you, this is not a commonly encountered species as an adult or as a larva. Arctia caja larvae look very different and they do not have the black protuberances on their body that cause those metallic reflections.

Latelly I have been researching these Arctia caja and Platarctia parthenos. Here is an image I found:

Note the big white spots. Arctia caja does not have white spots this big.

That image shown is © Jason
That image shown is © Jason Dombroskie from the Moth Photographers Group.

I agree with you, but i have never seen Platarctia parthenos larvae with those white spots. There is some variation between different populations. Both pictures are similar in that those small tubercles are present. Their colour can be black or white apparently. Arctia caja has very long hairs and spiracles visible. Younger instars are generally dark reddish.

The hairs were short and bristly. I still think it's a wooly bear. I wish I had collected it!

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