I dont guess you felt of the protrusions to see if they would push back inside or not? Kinda looks like a craw claw trying to be expelled.

.10 surface acre pond, 10.5 foot deep. SW LA. The epitome of a mutt pond. BG, LMB, GSF, RES, BH, Warmouth, Longear Sunfish, Gambusia,Mud Minnows, Crappie, and now shiners!!...I subscribe!!