Help identifying black widows?

Okay, I work in a grocery store, and it's not uncommon for me to find black widows in the grapes (if you eat grapes, this is good information to know). Usually they're dead, but today I found a healthy living specimen. And I was showing it to my coworkers and saying, "check it out, I found a black widow in the grapes!"

But they were all like, "I don't think that is a black widow." And I was like, "the hell it isn't."

But anyway, I wanted to prove them wrong, so I took the spider home and tried to identify the species. But I'm having trouble identifying it.

I assumed that it would be Latrodectus hesperus, since I've been reading that L. hesperus comes from the western USA. The thing is, the pictures I've seen of L. hesperus don't have broken hourglasses. The spider I just caught DID have a broken hourglass.

I also looked up L. mactans. But the pictures of L. mactans that I've found have ALSO shown solid hourglasses as opposed to broken hourglasses.

Now, I DID manage to find a species of black widow that has a broken hourglass (Latrodectus variolus). But from what I've been reading, L. variolus has red spots on the dorsal surface of its abdomen, while the spider I found had NO spots on its dorsal surface.

So, like, I KNOW it's a black widow. But what species could it be? Are there regional populations of L mactans or L hesperus that have broken hourglasses? Are there regional populations of L variolus that don't have spots on the dorsal surface of their abdomens?

Does anyone here know anything about identifying black widows?

The grapes probably originated from CA right?
It is more than likely L.hesperus. Sometimes L.hesperus appear to have broken hourglasses - sometimes they are very faint.
Location is what it boils down to.
Sounds like this is a perfect opportunity to educate your co-workers now!

JPD said:

The grapes probably originated from CA right?
It is more than likely L.hesperus. Sometimes L.hesperus appear to have broken hourglasses - sometimes they are very faint.
Location is what it boils down to.
Sounds like this is a perfect opportunity to educate your co-workers now!

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The grapes DEFINITELY originated from California, I'm just not 100% sure that the spider originated from California. While the spider propably originated from the same place as the grapes, it's POSSIBLE that the spider originated from anywhere between California and Northern Florida.

So, the spider could be L hesperus from california vineyards. That's the most likely scenario.

But it's also possible that an eastern L mactans somehow made it into the grapes after being put onto the shelf.

And, I've been reading that the range of L variolus extends into Northern Florida. Since I live in Northern Florida, I can't immediately rule that out either.

But Latrodectus hesperus does seem to be the most likely possibility, so that's what I'm going with. Much appreciated!

I think I automatically win by default just for knowing that there is more than one species of black widow found in the USA.

I'd be willing to bet it's L. hesperus. I've seen plenty of L. hesperus with broken hourglasses. On the other hand, none of the mactans I've personally collected have had them, and I've caught plenty (they're one of the most common spiders in parts of South Carolina).
Variolus I have no experience with.

I think I automatically win by default just for knowing that there is more than one species of black widow found in the USA.

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Very true my friend!
Anytime you would like to go Widow collecting for me in your native haunts let me know!