Is it possible to ID a spider by it's molt

[Godzirra]

Just wondering if it is so, last year i took a close up picture of a molting my husband found in our garage. It was big, red & leathery.

So if it is possible I'll probably put effort into finding the picture, it's been on my mind ever since.

[What]

Generally no, but if it happens to be a fairly distinctive species, it might be possible.

[Dark Raptor]

You can ID spider mostly to the family level (if you have all the parts ot the exuvium). And if you know which species are the commonest (or live in a specific habitat), you can guess which one is that. There are also very characteristic species that are very easy to ID, like European genus Atypus, which can't be missidentified with anything in my area :)

The best solution - give the exuvium to the arachnologist with the microscope ;)

[Widowman10]

it might be pretty hard to do, but it's possible. if you can get some pretty good pics of certain areas, and post em up here, you might get some guesses (who knows if you'll get the right one though... :rolleyes:).

there are some distinctive ones, and if you know what spiders frequent your area, that will help. around my house, i could tell you 75% of the time which molt belongs to which spider. and that's just because i know most of the species around my house.

[Godzirra]

this is the pictures i took
http://i3.photobucket.com/albums/y98/la_exotique/Ranchy/spidermolt02.jpg
http://i3.photobucket.com/albums/y98/la_exotique/Ranchy/spidermolt01.jpg

is it even a molt?

[What]

A dead mature male mygalomorph...

Maybe Myrmekiaphila sp...

[jsloan]

Looks like it might be a male Antrodiaetidae, possibly Antrodiaetus sp. Either that or Cyrtaucheniidae. I'm leaning more toward the first because of what looks to be a patch of spines on the ventral side of leg I in the second picture (you can see the spines poking out from either side of the leg. Taken together they look brushlike). Similar to to Antrodiaetus pacificus males I used to find in Oregon.

To better see, though, if you can remove that green thing wrapped up in the web with it, on its underside, that might help. Cyrtaucheniidae males will have a pronounced indentation, or c-shaped bend, on the metatarsus of leg I. Also, I can't tell from these pictures, but in Antrodiaetus the fovea will run longitudinally (front to back), while in Cyrtaucheniidae it runs transversely (side to side).

Both families are mygalomorph trapdoor spiders.

This isn't a molt, it's a dead spider. This looks like a male that was caught while out wandering around, probably looking for a female. As you can see, they make good food for other spiders.

Where in the US did you find this, what state?

As to identifying the species based on pictures, I doubt it. You might be able to if you take it to a specialist.

[What]

Also, I can't tell from these pictures, but in Antrodiaetus the fovea will run longitudinally (front to back), while in Cyrtaucheniidae it runs transversely (side to side).

Sorry in advance for how this will sound but... Are you blind?! The spider's fovea is quite clearly procurved. Which means it is either Myrmekiaphila or Promyrmekiaphila.

But I seem to remember that Godzirra is from somewhere on the east coast...hence Myrmekiaphila being the most likely option.(If she is in California then it is Promyrmekiaphila).

[jeff h]

I second What.
Also note the spider appears to have been the victim of a Theridiid or Pholcid.

Also, Godzirra-the images of your jumpers in the other thread are of regius and otiosus (the yellow and black females). Do you have images of the audax?

[jsloan]

Sorry in advance for how this will sound but... Are you blind?! The spider's fovea is quite clearly procurved.

Now that you mention it, yes it is. Chalk it up to my being at least half blind.

[Godzirra]

You guys are super, all very interesting.
I live in West Virginia, My house is in the woods - and right next to a ditch. The specimen was pulled out of the garage which is right next to the ditch.

Hope that helps.

Jeff, the Orange & black jumping spiders i think are Regius (very light orange color), I'll get pics of the Audax soon when it's not in an awkward angle hiding from me....he's pretty sturdy.

[jsloan]

Speaking of Myrmekiaphila, here is a recent "taxonomic review" of the genus by Bond and Platnick:

http://digitallibrary.amnh.org/dspace/bitstream/2246/5892/1/N3596.pdf

According to the authors, M. foliata is the only Myrmekiaphila found up to now in West Virginia.