Beach Flounder, Syacium latifrons
The Beach Flounder, Syacium latifrons, whose common Spanish name is lenguado playero, is a member of the Sand Flounder or Paralichtyidae Family, known collectively as lenguados areneros in Mexico. Globally, there are only eight members of the genus Syacium, six of which are found in Mexican waters, three in the Atlantic and three in the Pacific. All family members are left-eyed fish and have either a straight or arched lateral line.
The Beach Flounders have oval-shaped bodies with a depth that is 42 to 46% of standard length. Their eye side is a uniform brown color with numerous dark spots covering the head and body. Males have one or two dark lines between their eyes and the tip of their snout. Dark spots are found along the top profile of their head. Their body is darker in color than their fins. Their anal and dorsal fins have regular rows of dark spots, their caudal has indistinct spots, and their pectoral fin has four indistinct bars. Their blind side is yellow-white. Their head has a convex upper profile with a small concave notch between the tip of the snout and the top eye. They have a medium-sized mouth that ends under the front edge of their eyes. Their lower eye is slightly in front of their top eye. Their eyes are well separated by a flat spot with the gap being larger in males than in females. There is a distinct notch before the top eye on the snout profile. They have 63 to 74 anal rays and 81 to 93 dorsal rays. Their caudal fin has a wide base and is rounded. The pectoral fin on their eye side varies in length from half to twice the head length depending on sex with the males having exceeding long pectoral fins. They have seven or eight short fat serrated gill rakers on their lower arch. They are covered with large rough scales on their eye side and smooth scales on their blind side. They have straight lateral lines.
The Beach Flounders are bottom dwellers found over and within sandy and muddy bottoms at depths between 40 feet and 310 feet. They reach a maximum length of 25.0 cm (9.8 inches). They are opportunistic and well-camouflaged ambush predators that lie in wait half submerged on the ocean floor. They prey on small fish and a wide variety of crustaceans.
In Mexican waters the Beach Flounder are found in all waters of the Pacific with the exception that they are absent from Magdalena Bay northward along the central and northwest coasts of Baja.
The Beach Flounder can be confused with a four Sanddabs and three Flounders found in Mexican waters of the Pacific: the Bigmouth Sanddab, Citharichthys gilberti (12 to 16 gill rakers), the Five-Rayed Sanddab, Citharichthys mariajorisase (eyes set close together), Longfin Sanddab, Citharichthys xanthostigma (pointed snout), (the Oval Flounder, Syacium ovalis (eyes set close together), the Pacific Sanddab, Citharichthys sordidus (body depth 34 to 39%; 12 to 16 gill rakers), the Pompadour Flounder, Syacium longidorsale (first pectoral ray long), and the Speckled Sanddab, Citharichthys stigtmacus (12 to 16 gill rakers).
The Beach Flounder is small, rare and of limited interest to most. I catch about one per year out of 100 foot water over sand bottoms utilizing very small hooks baited with cut squid.
Beach Flounder, Syacium latrirons. Fish caught from coastal waters off Puerto Adolfo Lopez Mateos, Baja California Sur, April 2016. Length: 22 cm (8.7 inches).