The names of the two most common fish served at the bars on the Malecon and elsewhere in Penasco are known as "Pescado Mierda and Pescado Basura".
Funny thing that a sleepy quaint little sea side village on the shores of Mexico's marvelous Sea of Cortez can only regularly depend on "trash fish" to supply the needs of it's local eateries. This is mostly due to the stingy nature of the eateries and the fact that most of the quality fish caught here are shipped out and sold somewhere far from Rocky Point.
What is served depends on where you go and how it is prepared. Drunks at bars aren't too particular about what is on the menu as long as it's spicy and salty especially with a stupid name like buffalo wings del mar or pescado al disco. After eating such they can justify another round to wash the foul tasting crap down with.
As Broken states above Trigger Fish and the various local flat fish species collectively known as Flounder are common. The typical deep fried whole fish with head on, not scaled and guts still in is usually the Bay Bass locally called Cabrilla. After being hauled in with a trawl for shrimp or left dangling from a long line or a gill net for a day or two they are naturally long dead quite bloated and ripe with age.
The tradition in Mexico is to hide or mask that smell and taste of decay with a nice heavy dusting of hot chili powder, garlic powder and salt then deep fry them in some kind of foul reddish brown cooking oil that normally would have been tossed due to the natural rancid taste after days or weeks of use. A whole fish cooked like this is great entertainment for tourists and drunks at bars. The head with white sunken eye balls, the crappy scales that cover every bite, the endless tiny bones piercing your tongue and gums and whatever is still in the gut is of course right there on your plate. After picking through it for awhile they are usually just tossed in the trash or fed to the dogs and cats out back.
Another local dee-lite is the tasty dish known as ceviche. It can be served up with a variety of critters from Trigger Fish and Sierra's to shrimp and octopus.
Many people like to convince themselves that the meat has been "cooked" in the ceviche preparation process. How can anything be cooked in a raw liquid bath of lemon or lime juice with some garlic cloves drifting around in it? If lemon and lime juice can "cook" something then how can the Fruit Fly maggots that infest the fallen fruit in my yard exist on them??
All I can say on that subject is be sure to have a fresh roll of butt wipe and a gallon of fresh water handy to wash down your funky butt on the way back home when Senior Montezuma gets his final revenge.
Some places and I can only name a few do actually serve fresh fish, I really have no idea if it is local caught or not as Sam's Club is just up the street.
Capone's does have local Grouper, JJ's has fresh flat fish, the rest of them leaves me doubtful. Want some really good fresh local caught fish go to Jessie's on the way to the Malecon and cook it yourself.
Just saying,
JJ