Do mud deposition events on sandy beaches affect surf zone ichthyofauna? A southern Brazilian case study

► Mud events occur episodically at Cassino Beach, changing surf zone hydrodynamics. ► We examined the mud influence on the ichthyofauna inhabiting the surf zone. ► Mud sites exhibited the lowest richness and equitability values. ► Mud area higher abundance values are likely associated to small juvenile individuals. ► We proposed three hypotheses to explain juvenile concentration at mud areas.