Mountain spider - Aculepeira carbonarioides

Moved

… Lynette Elliott, 4 September, 2009 - 6:48pm

Aculepeira carbonarioides

Ok, so I think I have it. The image in The Insects and Arachnids of Canada Part 23 on page 180 is a good match for pattern. It also shows a hairier abdomen than packardii, which again matches. It is found in CO at higher elevations, such as alpine meadows. I believe this may be the first image of this species on the web??

My only slight hesitation is that the world spider catalog lists one more species, A. aculifera. The book I'm using to make the ID (above) doesn't recognize that species in our range. It claims we only have the two species carbonarioides & packardi.

… Lynette Elliott, 4 September, 2009 - 6:36pm

Congratulations, Lynette -

Looks like good detective work, and a useful INFO page. Based on what you write, this spider may well be the orb weaver A. carbonariodes.
I don't have the book you mention, & only occasionally dabble in spiders. I've been told a number of times that in most cases you need to dissect genitalia and good magnification for a positive ID.
The other species you mention, A. aculifera, is listed as occurring from the USA to Guatemala, on the Nearctic Spider Database (canadianarachnology). Herbert Levi (1992) included a description of aculifera in a paper mostly concerned with American Neoscona. You can download it in PDF format. I don't think this helps with ID from photos, though.

… Hartmut Wisch, 4 September, 2009 - 10:37pm

I don't have this book either...

I borrowed it through interlibrary loan from Colorado! I'm planning to put it to good use while I have it. And you were right that PDF article did not offer much, but thanks for pointing it out.

… Lynette Elliott, 4 September, 2009 - 10:55pm

WOW -

I should try more of those inter-library loans!
In case you haven't perused the CO collection records, here they are, several pages: DMNH. Mostly records of packardi, though of the 3 records for carbonarioides one is from "base of Andrews Glacier, Rocky Mountain National Park", Larimer County.

… Hartmut Wisch, 5 September, 2009 - 10:11am

What timing

I was trying to get into the DMNH when you posted this. It kept telling me 'not available', but your link worked perfectly. I'd say that info clinches the ID as aculifera was not found in CO. Thanks!

… Lynette Elliott, 5 September, 2009 - 10:42am

I've placemarked the coordinates for

John's spider, as well as the "base of Andrews Glacier" record & e-mailed the Google Earth view to you.

… Hartmut Wisch, 5 September, 2009 - 11:02am

I still think ID is correct BUT

It seems aculifera is found in CO & NM. See this site.

… Lynette Elliott, 5 September, 2009 - 11:18am

Great shots

I don't recognize this right off. It is very hairy for an orb weaver. The hairiness reminds me of Aculepeira.

… Lynette Elliott, 31 August, 2009 - 9:14am

Not an ID -

I merely recall seeing this shape and pattern in Neoscona, a genus of orbweavers.
Actually, Lynn, at least some Neoscona are very hairy. Still, I don't know whether this spider is in that genus. We'd need someone with more experience. Meanwhile, John, I recommend you check out information on the following two websites: Nearctic Spider Database, and the Colorado Spider Survey of the Denver Museum of Nature and Science (used to take my tour groups there).

… Hartmut Wisch, 31 August, 2009 - 2:19am