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Antrodiaetus riversi - Atypoides riversi

Antrodiaetus riversi - Atypoides riversi
Long Ridge OSP, Santa Cruz Mountains, Santa Clara County, California, USA
September 22, 2007
Here is a better photo that I took later. It is the same burrow.

Images of this individual: tag all
Antrodiaetus riversi - Atypoides riversi Antrodiaetus riversi - Atypoides riversi Antrodiaetus riversi - Atypoides riversi


Antrodiaetus riversi
This is without doubt Antrodiaetus riversi, formerly in the genus Atypoides.

Moved from Spiders.

Have you positively ruled out a wolf spider? I can vaguely make out the eyes, which don't look like the eye arrangement of a mygalomorph (or am I just seeing reflections off the chelicerae?). Any chance you can take an image of the spider itself, coaxing it out of the burrow and replacing it once you have a few images?

More info
I haven't positively ruled out anything :-) . I can say that the opening of the turret was about 12-15 mm. There were three in this area, one without the redwood needles, and more down the trail about 10 feet which I didn't personally see.
I'll put up a closer crop of the opening. I can't make out anything that looks like eyes except possibly a round shiny spot between the two middle legs.
The turrets were on the side of the trail, on the dirt wall coming up from the trail, under a mossy overhang with a tree above. It was a wooded area.
We did see a couple of wolf spiders on another trail off a grassy area, one carrying babies. They were much bigger and were more of a light tan color.

My mistake.
It was a reflection off the chelicerae that I was seeing....I suspect this is a juvenile mygalomorph of some kind then. An adult Atypoides is not a small spider! I had a male specimen once, taken by a friend near Bend, Oregon. Males have incredible horn-like processes coming off the jaws, so are easy to recognize. Females not so much:-) Detailed images of the actual spider will be necessary for even a family ID, and if these 'are' immature, not sure even that would help. You might consider pitfall trapping right now, for wandering adult male specimens of whatever this is.