Brown Widow with Egg Sac

Subject: Is this a Dangerous Spider – Sure looks like it to me
Location: West Los Angeles
July 10, 2017 5:39 pm
Hi Bugman,
As much as I love butterflies, I don’t get along with spiders. Can you please let me know if this one is dangerous?
These are the best pics Icould take, but if you enlarge them the spider is quite visible.
Signature: Jeff Bremer

Brown Widow and Egg Sac

Dear Jeff,
Both the Brown Widow Spider and her egg sac which are pictured in your image are quite recognizable.  According to BugGuide:  “The brown widow is highly variable in color. It may be almost white to almost black. Typically, it is a light to medium brown, with an orange-to-yellow hourglass marking on the underside of the abdomen; the coloration of the hourglass often is a good indication of this species. The leg segments are banded, with one half of each segment lighter in color than the other half. The back often has a row of white spots (rarely orange or light blue), and there are a few white stripes on each side. Darker individuals lack these markings and are difficult to distinguish from black widows. If an eggsac is present, this is the best identifying characteristic. Brown widow eggsacs are tan, spherical, and have many small tufts of silk sticking out from them. They resemble a ‘sandspur.’ The other widows make white, smooth eggsacs that tend to be pear-shaped. ” BugGuide also provides this information:  ” Widow Bites:  NOTE: It is recognized that this particular species of widow is most likely not medically significant (not an immediate medical concern to those who are bitten). The brown widow produces clinical effects similar to that of the black widow but the typical symptoms and signs being milder and tending to be restricted to the bite site and surrounding tissues. (Print Ref 1)  Brown widow spiders usually curl up into a ball, and drop to the ground as a primary defense. It is highly recommended that people leave this spider alone; observe, but don’t touch.  The brown widow is an extremely timid spider which has rarely been reported to bite.”  The Brown Widow is a non-native, introduced species that has gotten quite common in Southern California as well as the entire southern portion of the U.S.

Thanks Daniel,
It’s hard to know when to be worried and when not.

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