California tonguefish
Symphurus atricaudus
FAMILY
Cynoglossidae
TAXONOMY
Aphoristia atricauda Jordan and Gilbert, 1880, San Diego Bay, California.
OTHER COMMON NAMES
French: Langue californienne; Spanish: Lengua de perra.
PHYSICAL CHARACTERISTICS
Small, sinistral flatfish with the characteristic tonguefish teardrop-shaped body terminating posteriorly in a point without a distinct caudal fin. The small head has a pointed snout. The small eyes are set close together. A small, subterminal mouth
with small teeth best developed on the jaws of the blind side. Dorsal and anal fins are conjoined with the caudal fin, forming one continuous fin around nearly the entire body. Lacks a lateral line on either side of the body, lacks pectoral fins in adults, and has a pelvic fin only on the ocular side. Ocular side is uniformly medium to dark brown, with a series of complete or incomplete darker crossbands and with the posterior fifth of the body much darker than the anterior regions. Blind side is uniformly whitish or yellowish. Reach lengths to about 8.3 in (21 cm), but most are smaller, usually averaging only about 5 in (13 cm). Little is known concerning longevity, growth rates, or population structure of this species.
DISTRIBUTION
Inner continental shelf of the eastern Pacific from Washington to the Pacific side of Baja California Sur and along the western shore of Sonora and Sinaloa, Mexico.
HABITAT
Sand or mud bottoms at depths ranging from 9.8 to 328 ft (3–100m), with most adults taken between 98.4 and 262.5 ft (30–80 m). Juveniles tend to inhabit shallower waters than do adults.
BEHAVIOR
Little is known. Probably nocturnally active and also active at other periods of low-light levels. During the daytime it remains partially or totally buried in the sediment, except for the anterior head region.
FEEDING ECOLOGY AND DIET
Consume a variety of small benthic invertebrates, including harpacticoid copepods, amphipods, ostracods, nematodes, small bivalve mollusks, and polychaetes. Predators of California tonguefish include sharks, electric rays, stingrays, and various bony fishes.
REPRODUCTIVE BIOLOGY
Little is known. They spawn planktonic eggs from June to September; larvae hatch at about 0.08 in (2 mm). Larvae transform between 0.7 and 1 in (19 and 25 mm) in length and settle to the bottom during late fall and winter. Probably a serial spawner, producing several batches of eggs during a protracted spawning season.
CONSERVATION STATUS
Not threatened.
SIGNIFICANCE TO HUMANS
Of little commercial value, owing to its small size.
