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Photo#34659
Guide Plate for the Southern Black Widow - Latrodectus mactans

Guide Plate for the Southern Black Widow - Latrodectus mactans
The female is on the left and the male is on the right.

Is the size comparison accurate?

identification of L. mactans
This is a very good article but it still presents somewhat conflicting information about the identification of L. mactans.

The article says:
"The adult female black widow spider has a glossy jet black color all over, including body and legs. The only red marks are the bright red hourglass mark on the underside of the abdomen, and a red spot just behind and above the spinnerets."

But this diagram shows read marks on the dorsal side of the abdomen. I have seen some pictures where these marks are very distinctive. Do the marks disappear as the spider ages? Is this just a variation between individuals? Does L. mactans almost always have at least one read dot above the spinnerets?

Gut feeling
that the male is a bit smaller. I was amazed how small he was when I found one the other day. I thought it must be an immature male, but was ID's as mature.

 
Male Black Widow
I will make the male a bit smaller. Thanks for your help!

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