Tooth?

[Inkslinger10]

 This caught my eye while scouting (and wading, still in the low 90°'s in MO) an stretch of Sugar Creek that was new to me.

[Darktooth]

Not a tooth. There is no enamel.

[Inkslinger10]

I realized that and wondered, but I've seen croc teeth in this simulator condition?

 

[Fossildude19]

No serrations or growth lines, either. 

This is a rock, rather than croc.  

[Inkslinger10]

Yep, that was my instinct. "Go with your gut!" Lol. But post on Fossil Forum just in case! 

[sixgill pete]

When you post asking for an ID please give us some info on the geologic age of the sediments where your find is from. This information is crucial to getting a good ID. Most of us on hete have never heard of Sugar Creek in Missouri  some from outside of the U.S. may not have even hear d.c. of Missouri. Please read some of the pinned topics on how to get your item identified.

And unfortunately as @Fossildude19 said its a rock, not a croc. But keep looking.