Beach Flounder, Syacium latifrons

Beach Flounder, Syacium latifrons. Fish caught from coastal waters off Palmilla Point, Baja California Sur, August 2019. Length: 17.0 cm (6.7 inches). Identification reconfirmed by Dr. Benjamin Victor, Coralreeffish.com.

Beach Flounder, Syacium latifrons. Fish caught from coastal waters off Point Palmilla, Baja California Sur, April 2010. Length: 17.8 cm (7.0 inches).

Beach Flounder, Syacium latifrons. Fish caught from coastal waters off Point Palmilla, Baja California Sur, November 2020. Length: 19.3 cm (7.6 inches).

Beach Flounder, Syacium latifrons. Fish provided by the commercial fishermen of Bahía Kino, Sonora, January 2015. Length: 22.0 cm (8.7 inches). Photograph courtesy of Maria Johnson, Prescott College Kino Bay Center, Kino Bay, Sonora.

Beach Flounder, Syacium latifrons. Fish caught from coastal waters off Loreto, Baja California Sur, October 2019. Length: 23.0 cm (9.1 inches).

Beach Flounder, Syacium latifrons, Male. Fish caught from coastal waters off Loreto, Baja California Sur, October 2024. Length: 26.4 cm (10.4 inches). Identification courtesy of Dr. Benjamin Victor, Coralreeffish.com.

The Beach Flounder, Syacium latifrons, is a member of the Sand Flounder or Paralichtyidae Family, and is known in Mexico as lenguado playero. Globally, there are eight members of the genus Syacium, of which six are found in Mexican waters, three in the Atlantic and three in the Pacific Ocean.

The Beach Flounder has an 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 eyes are found on the left side with the 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 mature animals and in males than in females. There is a distinct notch before the top eye on the snout profile. Their anal fins have 63 to 74 rays; their caudal fin has a wide base and is rounded; their dorsal fin has 81 to 93 rays; and, their pectoral fin on the eye side varies in length from half to twice the head length depending on sex with the males having exceeding long first pectoral rays. They have 7 or 8 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 a straight lateral line.

The Beach Flounder is a demersal fish that is found over and within sandy and muddy bottoms at depths between 12 m (40 feet) and 95 m (310 feet). They reach a maximum of 26.4 cm (10.4 inches) in length as established by the fish photographed above. 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. The Beach Flounder is poorly studied with very limited information available about their lifestyle and behavioral patterns including specific details on age, growth, longevity, movement patterns, diet, habitat use, and reproduction.

The Beach Flounder is a resident of all Mexican waters of the Pacific Ocean with the exception that they are absent from Magdalena Bay, Baja California Sur, northward along the central and northwest coasts of Baja.

The Beach Flounder is most likely confused with the Toothed Flounder, Cyclopsetta querna (larger – maximum length 44 cm (17 inches), highly visible canine teeth); and also with four Sanddabs and three other Flounders found in Mexican waters of the Pacific: the Bigmouth Sanddab, Citharichthys gilberti (12-16 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%; 12-16 gill rakers), the Pompadour Flounder, Syacium longidorsale (first pectoral ray long), and the Speckled Sanddab, Citharichthys stigtmacus (12-16 gill rakers).

From a conservation perspective the Beach Flounder is currently considered to be of Least Concern with stable, wide ranging populations. They are small in stature, rare and of limited interest to most. I catch about one per year out of 30 m (100 feet) water over sand bottoms utilizing very small hooks baited with cut squid, and interestingly never near the beach.