The prefix "mulloid" in its genus name comes from the Latin mullus, meaning "soft," while "ichthys" is Greek for fish.

[3] M. dentatus is found in the Central-Eastern Pacific Ocean, from southern California to Peru.

Its range includes the Galápagos Islands and is rare north of the Baja California peninsula.

[1][3] It mainly sticks to the coast and coral reefs, living in the sandy, muddy, and rocky bottoms near the shore.

[2] M. dentatus was evaluated by the International Union for Conservation of Nature in May 2007, which placed it as Least Concern on the IUCN Red List.