might be helpful to review how fish are sold at la poissonerie.
y'all help me here, but I think: daurade is usually sold in whole fillets; wahoo is usually sold in steaks (also called darnes); tuna usually sold in pavés or tranches (thick slices from large filets) or as filet at the tail end; smaller fish like fino or oeil de boeuf usually sold whole and cleaned (entier et vidé) or filleted for you; langoustes always sold live but will split and clean guts for you if you keep on ice and cook within couple of hours.
please feel free to add to or edit.