Large black spot on Lysmata shrimp

[Calm Blue Ocean]

This guy is close to 2 years old and recently developed this large black spot in the middle of his back. My first guess is an injury (he lives with my tiger pistol shrimp, yes, they really share a cave). I've seen mentions of a black spot disease of some sort that cleaner shrimp can get but I don't think this matches that description. His behavior seems normal, and he is active and eating well. Is it likely that this sort of thing will clear up with his next molt or am I looking at something more insidious?

 

[G Santana]

I would feed it well, hopefully you could accelerate its molt and perhaps it will molt out of that bruise. My blood shrimp molts every 3 weeks but when it's fed more than average, it will molt quicker.

 

[vetteguy53081]

Its a bacterial infection that sometimes is on a given shrimp and often goes away during a molt

 

[Calm Blue Ocean]

Good news, he molted tonight, and the spot is pretty much gone. There might be a very slight discoloration where it was but nothing so obvious as it was before.