Pacific Sanddab, Citharichthys sordidus

Pacific Sanddab, Citharichthys sordidus, Male. Fish caught from coastal waters off Sitka, Alaska, September 2015. Catch, photograph and identification courtesy of Chris Wheaton, Fullerton, California.

Pacific Sanddab, Citharichthys sordidus. Fish caught from coastal waters off  Catalina Island, California, September 2017. Catch, photograph and identification courtesy of Chris Wheaton, Fullerton, California.

Pacific Sanddab, Citharichthys sordidus. Fish caught from coastal waters off the Channel Islands, California, August 2019. Length: 24 cm (9.4 inches). Catch, photograph and identification courtesy of George Brinkman, Guelph, Ontario, Canada.

Pacific Sanddab, Citharichthys sordidus. Fish caught from coastal waters off Tijuana, Baja California, February, 2023. Length: 28 cm (11 inches). Catch, identification and photograph courtesy of Luke Ovgard, Klamath Falls, Oregon.

Pacific Sanddab, Citharichthys sordidus. Fish caught from coastal waters off Puerto Adolfo Lopez Mateos, Baja California Sur, October 2019. Length: 30 cm (12 inches).

Pacific Sanddab, Citharichthys sordidus. Fish provided by the commercial fishermen of the greater San Diego area, San Diego, California, October 2014. Length: 30 cm (12 inches).

The Pacific Sanddab, Citharichthys sordidus, is a member of the Sand Flounder or Paralichthyidae Family, and is known in Mexico as lenguado moteado. Globally, there are twenty-four members of the genus Citharichthys, of which sixteen are found in Mexican waters, eight in the Atlantic and eight in the Pacific Ocean.

The Pacific Sanddab is a flatfish that has an elongated oval body with a depth that is 34% to 39% of standard length. Their eye side is a dull light brown, mottled with brown or black, and sometimes yellow or orange. Their blind slide is off-white to tan. Upon collection they quickly fade to a uniform brown color. Their head has a medium-sized mouth with large eyes that are set above the body with their lower eye being longer than the snout and in front of their top eye. There is a concave pronounced ridge between their eyes. Their anal fin has 67 to 81 rays; their caudal fin is slightly rounded; their dorsal fin has 86 to 102 rays and originates just behind the anterior of the top eye; and, their pectoral fin reaches the middle of the lower eye when folded forward (a key to identification). They have 15 or 16 gill rakers on their lower arch. They are covered with large scales and their lateral line is straight and gradually arches over their pectoral fin.

The Pacific Sanddab is a demersal species that is found over sandy and muddy bottoms or within shell debris at depths up to 710 m (1,800 feet). Young fish can be found in coastal estuaries. They reach a maximum of 41 cm (16 inches) in length and just under 1.0 kg (2 lbs 0 oz) in weight, with females being large than males; however, most weigh less than one-third of a pound. As of January 1, 2023, the International Game Fish Association world record stood at 0.45 kg (1 lb 0 oz) with the fish caught within the Puget Sound, Washington in October 2017. The males have orange spotting on the dorsal side. They are unique among flatfish for being good swimmers; they have been observed cruising up to at least ten feet above the ocean floor. They consume a wide variety of crustaceans and small fish and are preyed upon by a variety of marine mammals, larger fish, and sea birds. They are masters at camouflage, rapidly changing colors to match their substrate. They are a non-migratory species typically spending their entire life within a two-mile circle. They have a lifespan of up to thirteen years. The Pacific Sanddab 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 Pacific Sanddab is a resident of Mexican waters of the Pacific Ocean but has a limited distribution being found only in coastal waters off Baja California and Baja California Sur along the entire west coast of Baja in coast.

The Pacific Sanddab can be easily confused with the Beach Flounder, Syacium latifrons (deeper body, pointed tail), the Gulf Sanddab, Citharichthys fragilis (long pectoral fin; 18 lower gill rakers), the Longfin Sanddab, Citharichthys xanthostigma (pelvic fin reaches the snout tip), and the Speckled Sanddab, Citharichthys stigmaeus (short pectoral fins don’t reach eyes when folded forward; small black dots covering body).

From a conservation perspective the Pacific Sanddab has not been formally evaluated. They are a strong component of the commercial fishery and are sold whole in supermarkets, however, they have a relatively short shelf-life. The majority of fish are taken by deep water trawls. Historically they were dried and exported to China for human consumption or used as a component of animal food. They are a targeted species of recreational fishermen taken off piers, jetties, and shores. They are also a seasonal favorite of Southern California party boats.