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Photo#40822
Spider - Coras

Spider - Coras
Coloma, Berrien County, Michigan, USA
January 11, 2006
Size: 2.5 cm
Found today in crevice between landscaping stones. Had a sheet web with a tunnel.

Images of this individual: tag all
Spider - Coras Spider - Coras

amaurobiid?
In just looking at the eyes, there seems to be some discrepancy. They appear to be too high and the lower anterior spacing seems a tad too much. I think we should compare with ferox. Are not eyes suppose to be diagnostic within Amaurobius

Reminds us of
. See the discussion we have there with Jeff. It will be interesting to see what these are when we finally get them Id'd. Great images!

 
Definitely looks
to be the same Genus if not specie. If I remember right I use to see these spiders low to middle of fence posts in summer with a fairly large horizontal web (8-12") and a tunnel leading to a dark place. Skittish when walked up on but toss a bug in and they will come out.

 
your description is perfect for the
Agelenidae - Funnel-Web Spiders, which can be found in the guide here, but we don't think your image is a member of that family. It will be interesting to see what the experts discover. Knowing where you found it and the kind of web it had should be a great help.

 
Very interesting.
Coras builds a funnel web, but as Eric mentioned, is no longer a member of Agelenidae, and it is not a cribellate spider. ("hacklemesh weaver" generally pertains to cribellate spiders)
Here are some interesting facts and remarks about this topic from the

Newsletter of the Biological Survey of Canada (Terrestrial Arthropods) Volume 18 No. 1, Spring 1999
Canadian Spider Diversity and Systematics
Robb Bennett

Dictynoidea and Amaurobioidea
Although generally accepted as valid superfamilies, Dictynoidea and Amaurobioidea remain poorly defined and their family level systematics is in disarray (Coddington and Levi 1991). Classically, all members of both groups were considered to be cribellate (the cribellum is a distinctive silk production organ found in some spiders and derived from the ancestral anterior median spinnerets). Lehtinen’s (1967) exposure of “Cribellatae” as paraphyletic and defined by a plesiomorphic character (the cribellum) marked the beginning of the current era of spider systematics which has resulted in massive restructuring of the classification of Araneae from family to subordinal levels. Dictynidae and Amaurobiidae are now seen to contain both cribellate and ecribellate genera, many of the latter transferred there after the sundering of the old, paraphyletic Agelenidae (e.g. Blabomma and Cicurina are ecribellate dictynids; Coelotes, Coras, and Wadotes are ecribellate amaurobiids). The two superfamilies have Canadian representatives in Dictynidae, Cybaeidae, and Hahniidae (Dictynoidea) and Amaurobiidae, Agelenidae, and Titanoecidae (Amaurobioidea). The taxonomy and systematics of amaurobioids and dictynoids has been studied actively in recent years (e.g. Bennett 1987, 1988, 1991, 1992; Griswold 1990) but little has been well resolved above the genus level, various genera are placed only tentatively or uncertainly within one or the other superfamily, and most of the families lack clear diagnosis (except for Amaurobiidae – Griswold 1990). No doubt, if this area remains active, major changes are yet to come.

 
Web similarities --
Howell and Jenkins state that "Coras medicinalis builds an extensive, broad, platform-like web that is equipped with a tubular or funnel retreat. Their webs are often constructed beneath overhanging rock ledges where the platform of the web sags somewhat."

 
Amaurobiidae?
These remind me of something like Coras or Wadotes, which ONCE were in the Agelenidae, but are now in the Amaurobiidae. Go figure.

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