Pacific Sanddab, Citharichthys sordidus
The Pacific Sanddab, Citharichthys sordidus, whose common Spanish name is lenguado moteado, is a member of the Sand Flounder or Paralichthyidae Family, known collectively as lenguados areneros in Mexico. Globally, there are twenty-four members of the genus Citharichthys, nine of which are found in Mexican waters, one in the Atlantic and eight in the Pacific.
The Pacific Sanddabs are left-eyed flat fish with a straight lateral line that gradually arches over their pectoral fin. They have elongated oval bodies 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. They lack an anal spine but have 67 to 81 anal rays. Their dorsal fin has 86 to 102 rays and originates just behind the anterior of the top eye. Their caudal fin is slightly rounded 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 and are covered with large scales.
The Pacific Sanddabs are bottom dwellers found over sandy and muddy bottoms or within shell debris at depths up to 1,800 feet. Young fish can be found in coastal estuaries. They reach a maximum length of 41 cm (16 inches) and just under two pounds in weight, with females being large than males, however, most weigh less than one-third of a pound. The males have orange spotting on the dorsal side. They are unique among flat fish 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.
In Mexican waters the Pacific Sanddab have a limited distribution being limited to the entire west coast of Baja.
The Pacific Sanddab can be easily confused with the Beach Flounder, Syacium latifrons (deeper body, pointed tail), the Gulf Sanddad, 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).
The Pacific Sanddabs 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.
Pacific Sanddab, Citharichthys sordidus, male. Fish caught from coastal waters off Sitka, AK, September 2015. Catch, photo and identification courtesy of Chris Wheaton, Fullerton, CA.
Pacific Sanddab, Citharichthys sordidus. Fish caught from coastal waters off Catalina Island, CA, September 2017. Catch, photo and identification courtesy of Chris Wheaton, Fullerton, CA.
Pacific Sanddab, Citharichthys sordidus. Fish caught from coastal waters off Redondo Beach, California, August 2016. Length: 23 cm (9.1 inches). Catch, photo, and identification courtesy of Ben Cantrell, Peoria, IL.