L= 0.75" (19mm). All brown with difficult-to-see,
violen-shaped marking right behind eyes. Brown Spiders
have only 6 eyes (unlike most spiders which have 8), and the eyes are
arranged in three pairs (see Vetter
1999 for more information).
NATURAL HISTORY: Dangerously Venomous (potentially
fatal -- when bitten, call the Arizona
Poison and Drug Information Center
at 626-6016 in Tucson and 1-800-362-0101 elsewhere in Arizona.).
The venom generally causes a sore that enlarges over time (see picture
to right) and may cause permanent tissue damage (and possible death)
if not treated by a physician (see Vetter
and Visscher 1998 for more information). Brown spiders use irregular
webs built underneath rocks and debris to catch their arthropod and
other invertebrate prey.
confuse the dangerous Brown Spider with the harmless Wolf
Spider (Hogna carolinensis). Wolf Spiders have 8 eyes instead
of 6 and often are larger and stockier than Brown Spiders. Also Wolf
Spiders have a lighter, peach-colored stripe down their cephalothorax
(combined head and thorax) compared to the darker, brown, fiddle-shaped
marking on the cephalothorax of the Brown Spider.