Legs are near the head of these critters, so apparently beetle larvae.Looks like Hive beetle larva, pull it out and see if it has 6 legs near the head, if so it is Hive beetle. Moth larva have legs down the body and you often find webs with them.
This is the former. Bottom board has a screen with a tray that slides in under the screen to catch stuff.If this is on a tray under a screened bottom, it means nothing. If it's on the bottom board where the bees can get to it, I would worry more. But that depends on how many etc.