Small fly? Grain beetle? Neither? NJ, USA

[bugs9374]

About one week ago I disposed of everything in my pantry and bought dozens of airtight plastic containers to store all foods in after finding several sawtoothed grain beetles in my flour.

I suspected I was getting some flies out of my shower drain on the second floor, taped over the drain, and my suspicions were confirmed. After pouring a pot of boiling water down the drain, I put the pot on the stove to cool, and later came back to this bug in the bottom of the pot. It is very small, about 4mm, the size of a typical "gnat" type insect. I just cannot tell what it is. I wish I could take clearer photos, these are from a cell phone camera.

I'm trying to figure out if I still have some grain beetles around if or this was just a one off bug that found its way in, or maybe even another fly from a drain. Thanks for you help in advance!

Hudson County, NJ, USA

Photos here: imgur.com/a/IhSyG1o

[kevinkk]

That looks like a beetle.
There are small flies that appear out of nowhere seemingly, about a week ago, we
had some unusual warm weather and after cleaning up fallen leaves there were small flies
in the hundreds, all attracted to light colored surfaces.
Mom panicked, called it an invasion of millions...and used 2 cans of bug spray.
Luckily, for me all my livestock was safely in the fridge.

[bandrow]

Greetings,

Your images are a bit unclear, but I'm confident that your specimen is a small species of ground beetle in the family Carabidae. It's likely something in the Bembidiini, close to the genus Tachys. For some images, start at the link below and surf the gallery on BugGuide and see if you find something close.

BugGuide Tachys

They are readily attracted to lights, and can be difficult to ID to species, even by specialists. In a home, they'd just be an adventive - they're mini-predators on other tiny invertebrates and are harmless to humans, and not likely to persist indoors. Probably came in through a screen or door jamb and ended up in hot water!

Cheers!
Bandrow

[bugs9374]

That has a pretty strong resemblance to my beetle, thanks!. I've only seen just the one, so it does seem to be one that wandered in somehow.

I did also see (unrelated) about half a dozen small flies had gotten through the screen in my bathroom window and were trapped between the screen and glass. We had some warm, rainy weather so I guess they were attracted to the bathroom lights through the window!