The Sand Flounder Family – Paralichthyidae
The fish of the Sand Flounder or Paralichthyidae Family includes the Sanddabs and Flounders. They are known in Mexico as lenguados areneros. They have variable shapes with oval to elongated highly flattened disc-like bodies. Most species reach a maximum length of less than 25 cm (10 inches), however a few measure up to 150 cm (60 inches). Members of this family are found globally with one hundred fourteen species that have been placed in fourteen genera. The majority are left-eyed but some species have reversals with as many as 50% of their population being right-eyed. They can have either a straight or an arched lateral line that is highly visible on both sides of the body.
The head of the Sand Flounders has an asymmetrical protractile mouth and a prominent lower jaw. Their anal and dorsal fins are not attached to their caudal fin. Their dorsal fin is long and originates above their upper eye. They have pectoral fins on both sides of their body and symmetrical pelvic fins with short bases also on both sides of their body. None of their fins have spines. Their lateral line varies; it is highly arched in Hippoglossina, and the majority of Paralichthys and Xystreurys, and is straight in Citharichthys, Cyclopsetta, Etropus, and Syacium. Most are a uniform brown or gray on their eye side and many have spots, blotches, or ocelli; their blind side is typically off-white. The rear portion of the body is dark in some males. Some species are sexually dimorphic with differences in fin lengths. Their gender can easily be determined by holding them up to the light – females have long ovaries that extend back into their tail whereas males do not. Reproduction is oviparious with planktonic eggs and larvae.
The Sand Flounders are bottom-dwelling predators, usually burrowing partially or almost entirely in sand or soft mud. They are capable of rapidly changing color to match their background. Most feed on or near the bottom, but some of the larger species will rise off the bottom to capture prey. Most reside in shallow water and are found at depths of less than 600 feet. Larger specimens are good food fish and are sold commercially. They are caught via trawling, seining, and hook-and-line and marketed fresh, frozen, or as a component of fish meal. One species, the California Halibut, is a major targeted species by recreational anglers. They have been dated to 7.6 to 8.6 million years via fossils discovered in Southern California.
There are nineteen members of the Sand Flounder Family presented in this website:
Beach Flounder, Syacium latifrons
Bigmouth Sanddab, Citharichthys gilberti
Bigmouth Sole, Hippoglossina stomata
California Halibut, Paralichthys californicus
Channel Flounder, Syacium micurum
Cortez Halibut, Paralichthys aestuarius
Dappled Flounder, Paralichthys woolmani
Fantail Sole, Xystreurys liolepis
Foureye Flounder, Hippoglossina tetrophthalma
Fringed Flounder, Etopus crossotus
Gulf Flounder, Paralichthys albrigutta
Gulf Sanddab, Citharichthys fragilis
Intermediate Flounder, Etropus ciadi
Oval Flounder, Syacium ovale
Pacific Sanddab, Citharichthys sordidus
Panamic Flounder, Cyclopsetta panamensis
Peruvian Flounder, Etropus peruvianus
Speckled Sanddab, Citharichthys stigmaeus
Toothed Flounder, Cyclopsetta querna