Odd little spider - Ero canionis

Moved

Moved from Spiders.

… Lynette Schimming, 20 September, 2009 - 8:43pm

Ero canionis

This has to be Ero canionis, family Mimetidae. It resembles Ero
furcata: http://www.edderkopper.net/Mimetidae.html
http://www.treknature.com/gallery/photo49388.htm
which is non-local. The 2 dorsal humps are real humps
but the lateral ones are (to a great extent) optical illusions created by coloration.

… Lynette Schimming, 20 September, 2009 - 8:41pm

Of course! And one can even s

Of course! And one can even see the series of spines on legs I and II. And now that I think about it, I've also seen this defensive position in Ero.

However, I'm not so convinced about the optical illusion -- looking at the second image, the rear lower bump seems quite prominent. We have two species here in Europe that have the double pair of protusions: E. aphana (listed as introduced in Queensland) and E. tuberculata.

What about the other (two?) Nearctic species: E. lodingi and E. leonina (I'm assuming that E. pensacolae is outside of your area)

Thanks for straightening out this riddle.

-K

[Was just looking at the other Eros images here and my own collection (including one image from Rod) and I must say: they all look strikingly similar (to me, at least). Perhaps in the flesh, with measurements, etc., they are more easily distinguished from one another, but if I didn't know where the specimen came from, I don't think I could separate them without looking much more closely.]

… Kevin Pfeiffer, 21 September, 2009 - 12:57am

Pretty easy according to Rod

He's collected 50 species and they've all turned out to be Ero canionis. Of course there is always a first time. Maybe I'll try to find it and get some other images. I put the ranges on the genus page. I guess the only other possibility is leonina - (aka furcata).

… Lynette Schimming, 21 September, 2009 - 8:45am

Reminds us of your

NoCar image

, but ...

… john and jane balaban, 19 September, 2009 - 10:02pm

I don't think it's Episinus.

I don't think it's Episinus. My first thought was Hyptiotes, of which there are several Nearctic species. I remember reading something about the significance of how many "humps" are visible in the rear view, but I don't recall if this was in connection with Hyptiotes or something else...

-K

… Kevin Pfeiffer, 20 September, 2009 - 5:12am

Or another orb weaver?

Hmmm, I'm not yet so sure about the Uloboridae. Perhaps another orb weaver? Time to pull out Levi's guide to the genus, perhaps.

Actually, I'm reconsidering my rash dismissal of Episinus. There's Episinus angulatus, for example, that seems to bear consideration --- oops, that's a Palearctic species. :-(

-K

… Kevin Pfeiffer, 20 September, 2009 - 5:35am

There is a certain similarity

There is a certain similarity here to the image of Philoponella oweni (Chamberlin, 1924):
http://www.canadianarachnology.org/data/spiders/6331

But this species is found in the southwestern US. If it's in the Uloboridae, it almost has to be U. gertschi, doesn't it? I don't find any other candidates for the northwest.

-K

… Kevin Pfeiffer, 20 September, 2009 - 6:24am

Yes

good thinking. I've sent the images to Rod, I'm hoping they are obvious to him.

… Lynette Schimming, 19 September, 2009 - 10:29pm