What is this?

[CHSUB]

Came from Tampa Bay Live Rock.

 

[Subsea]

Looks a little like a bristle worm.

 

[CHSUB]

Looks a little like a bristle worm.

Maybe? It’s very hard, almost like armor and thick as my finger. Not like any bristle worm I have ever seen, but it could be?
Thanks

 

[Subsea]

10,000 species

Members of the annelid family, the term bristle worm encompasses more than 10,000 species. Generally found in the ocean (but also occasionally in fresh water), they're characterized by segmented bodies with bristle-like protrusions—called chaetae—along their sides.Nov 21, 2023

All About Bristle Worms - The Spruce Pets​

The Spruce Pets

 

[ISpeakForTheSeas]

Came from Tampa Bay Live Rock.

The picture is pretty blurry, but my first thought would be a sea cucumber of some variety.