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Help identify red crab-like spider - Antrodiaetus montanus - male

Help identify red crab-like spider - Antrodiaetus montanus - Male
Eagle Mountain, Utah County, Utah, USA
October 10, 2008
Size: 2"
I live in Eagle Mountain, Utah, United States. I found this spider in my garage on the ground hiding in a crack in the foundation. No webs nearby. I was surprised because I had sprayed the entire garage with bug spray which said it would also kill spiders. It had killed other spiders like wolf spiders. I poked this one with a stick to see if it was alive and it was but it moved slowly and sort of disoriented/drunken back and forth as if it were drawing a star on the ground, so it was probably dying slowly.

It was the afternoon. It's dry here and Eagle Mountain is very desert like. Not a lot of houses. Lots of wide open fields. We see all kinds of bugs. This one looked like it could be a hobo spider to me, but it only has one cluster of eyes. Also the pattern on the back does not match, and it's reddish not brown.

Very large boxing glove pedipalps so I believe it is a male seeking a female before it dies.

I believe you can see spinnerets on the abdomen so it must be a capable of building webs or something.

The thorax resembles a crab shape to me.

Fuzzy legs.

Any ideas what it could be?

Moved from Antrodiaetus.

Folding-Door Spider
Looks like something from Family Antrodiaetidae.

yes, how about Antrodiaetus unicolor?
I can see a lot of similarities. Maybe an expert can say for sure. Neat spider!

Yes, exactly! Thank you! :)
Yes, that's exactly it! Just like this one:

He was even doing that defensive posture where he sucks all his legs in like that! I wonder if that is unique to this spider or a general spider defense tactic?

Thank you.

great pet?
From what I've read, their bite is not a threat to humans and they are very non-aggressive and will even try to continue running when cornered. Some people keep these spiders as pets:

Red Trapdoor Spider

Red Trapdoor Spider (The Failed Hunt)

my african red trap door spider digging her burrow

Trapdoor spider attacks chopstick

Not unicolor
Just like the hobo, unicolor isn't found in Utah. A. montanus is more likely.

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