It almost looks like a black Blister Beetle, but not quite. Best guess.

Those ribbed wing covers have me thinking ground beetle. You may want to ask in the Insects forum. Where are you located?

tj

Ground beetle would be my guess as well. In most cases they are considered beneficials. They are predatory carnivores, consuming any invertebrates they can catch and leaving plant parts alone.

It's not a root weevil?

I really doubt it. We have lots of root weevils in my area. They tend to be smaller, more triangular in shape and almost wholly nocturnal.

There's a free app you can get called picture insect that is good at identifying insects from your photos. If you get it, let us know what it thinks!

App says asiatic oak weevil

I thought it had that weevilish look. The weevil family can be frustrating! The larvae feed on roots and are inaccessible, then the adults come out and chew notches out of the edges of leaves. Hopefully you only have a few and can ignore them. I get a lot of the vine weevils in my yard and they especially like to make a mess out of the leaves of hydrangeas, but they are very hard to battle so I mostly just ignore them. Was it eating your tomato leaves or just wandering around?

Looks very much like a dark version of the ilttle leaf notchers and Sri Lankan weevils we get here...