Wednesday, November 16, 2016

Along came a spider

We were walking along a trail in Bodega Bay last night when I noticed a rather large invertebrate moving quickly across the path.  I was a little surprised by its size, so I bent down to take a closer look with my headlamp.  I couldn't help saying, "Whoa!" out loud, so Eric turned back to see what it was:


This is a large spiderfrom leg tip to leg tip it was ~5 cm (2 inches) long!  Here's a picture with a ruler for scale:


I'm pretty sure it's a "false tarantula."  (It's smaller than a true tarantula, and has finer hairs.)  Within this group, it sounds like the most common species in this area is Calisoga longitarsus.  (If there are any spider experts out there who can confirm the identification, I'd appreciate any feedback.) 

When the spider started to walk away, Eric placed the ruler in front of it so I could try to get one more picture.

Here's what happened:


The spider reared up on its hind legs, raised its front legs, and exposed its impressive fangs (see close-up below).


Although they live in burrows, during the fall the males walk around looking for females.  Best to let them continue along their way!

I'm curious Have you seen this species locally?

5 comments:

  1. Yikes!!!!!! I would stay far away!!!! he is scary looking. :)

    ReplyDelete
  2. Hi, Jen!

    Yes, we gave this spider lots of respect! It actually didn't seem that interested in us, unless we got too close, when I presumed it then felt threatened.

    :) Jackie

    ReplyDelete
  3. Along came a spider, indeed, but is was not so itsy bitsy. Thanks for sharing. Very cool!

    ReplyDelete
  4. I sent this link on Facebook with my friends Charles Griswold, retired (and world-wide respected) Arachnologist at the Calif. Academy of Sciences, and his wife Teresa Meikle, an entomologist. Charles confirmed your identification, and Teresa had this further comment to make:

    "Great pictures! They do have a startling defensive pose when threatened, They will follow through with a bite if you don't back off. A friend of ours, a professional violinist, had one of these as a pet until it bit her. Our friend had a numb finger for a few days, but was fine after that. She gave us the spider, which lived for another 10 years, and our friend is still an awesome violinist."

    ReplyDelete
  5. Yes, that's Calisoga longitarsus, which is sometimes called the aggressive false tarantula because of it's immediate defensive behavior which you witnessed. I live in Bodega, where they are abundant---in late summer I see their burrows all over the yard, and in winter during rains, they routinely come into our living room (our old farmhouse settles every which way, so there is a large gap under the front door). I occasionally keep one or two of the trespassers; currently have a female I've had for 5 or 6 years, and had another female for 8 years. One produced a batch of offspring which I released outdoors, but the current specimen has not, despite repeated matings I've observed with different males over the past couple of years. The spiders are also common on the Santa Rosa Plain, where they often get caught in pitfall traps set for tiger salamanders.

    ReplyDelete