miketroll 的鑑定

I guess this is a spider burrow: a conical silk-lined structure incorporating forest debris. Seen in a forest of Douglas Fir and Coast Redwood.

Several others were nearby with smaller apertures; the fourth photo is one of these.

Similar structures with the Foldingdoor Spider Anthrodiaetus riversi have been posted from Pepperwood.

Most of my attempts to illicit strike responses from turret spiders end in failure, but for whatever reason Trent was able to get this one to cooperate. I tried to reciprocate but again without luck. Trent was gently stroking the edge of the turret with a twig, whereas I was poking it, so maybe the key is to immitate a smaller insect. There's anecdotal evidence to suggest that they eat ants, so maybe think ant-sized movements. Also, you need to do it under cover of full darkness for them to be staged near the burrow entrance (though they seemed willing to strike under flashlight illumination).

Note the deep, transverse foveal groove and the sclerite on the abdomen, both indicative of the former genus Atypoides (Adams 2014).

Turret spider burrow

http://en.wikipedia.org/wiki/Turret_spider

The Natural History of the California Turret Spider Atypoides riversi (Araneae, Antrodiaetidae): Demographics, Growth Rates, Survivorship, and Longevity
Leonard S. Vincent
Journal of Arachnology
Vol. 21, No. 1 (1993), pp. 29-39
Published by: American Arachnological Society
Article Stable URL: http://www.jstor.org/stable/3705376