I was thinking of how Barty Crouch Sr. was killed. After that was he (and other bodies) visible on the map?
It’s never specified, but the map likely won’t show dead bodies.
The Marauder’s Map was created so that James Potter and his friends could sneak around the castle without being caught. Having it still showing people’s corpses after they’re already dead wouldn’t be very useful to them, since dead bodies wouldn’t stop them from doing mischief. Its main purpose is to show the movement of every person in Hogwarts. (It shows ghosts as well, who are all ‘dead’ but still moving, able to speak, and capable of disrupting their plans.)
“It was a map showing every detail of the Hogwarts castle and grounds. But the truly remarkable thing was the tiny ink dots moving around it, each labelled with a name in minuscule writing. Astounded, Harry bent over it. A labelled dot in the top left corner showed that Professor Dumbledore was pacing his study; the caretaker’s cat, Mrs Norris, was prowling the second floor, and Peeves the poltergeist was currently bouncing around the trophy room.”
- Harry Potter and the Prisoner of Azkaban, Chapter 10 (The Marauder’s Map)
The J.K. Rowling Pottermore writing on the Marauder’s Map goes into further details on how it was created, and the charm they used for that was intended to allow them to track the movements of everyone in Hogwarts. This probably wouldn’t apply once they’re dead and no longer moving.
The magic used in the map’s creation is advanced and impressive; it includes the Homonculous Charm, enabling the possessor of the map to track the movements of every person in the castle, and it was also enchanted to forever repel (as insultingly as possible) the curiosity of their nemesis, Severus Snape.
- The Marauder’s Map (Pottermore)
Though we don’t know for sure, it seems unlikely that the Marauder’s Map would show corpses.