Bottomfish
Buy Your License Online! Buy Your License Online!

Bottomfish Identification: Flatfish

Flathead Sole
Hippoglossoides elassodon

Occasionally caught off the Washington coast by commercial harvesters using otter-trawls and longline gear.  They are rarely caught by recreational harvesters within Puget Sound.

Description: A right-eyed flatfish with a very flat, oval body shape. The eyed side is dark olive brown to reddish gray-brown, sometimes with dusky blotches. The blind side is white and translucent in places. Both dorsal and anal fins tend to have dusky blotches, but not regular banding (see starry flounder). This species has an angular caudal fin with the longest rays at the center. The lateral line is nearly straight with a low arch over the pectoral fin.  There is no accessory dorsal branch, but an anterior branch runs almost to the rear edge of the upper eye. Flathead sole have a medium to large mouth with one row of sharp conical teeth in both jaws. The maxillary extends to below the middle of the lower eye. The eyes are large with a narrow ridge and 1 – 2 rows of scales between them. This species has a strong anal spine. Pores are present below and behind the lower eye, but may be hard to see.  The flathead sole is very similar to the petrale sole, but the upper jaw of the petrale sole has two rows of teeth and the lower jaw has a rounded rear ridge.

Maximum Size: To 56 cm (22 in) in length, and 1.56 kg (3.4 lbs) in weight.

Maximum Age: At least 27 years for females and 30 years for males.

Range/Habitat: Flathead sole range from the seas of Japan and Okhotsk, across the Bering Sea and to the coast of North America as far south as Point Reyes, California.  This species lives on soft, silty or muddy bottoms at depths of up to 1,050 m (3,440 ft).   It is most commonly encountered from 100 to 247 m (328-810 ft).

Sources: 

  • Froese, R. and D. Pauly. Editors. 2011.FishBase. World Wide Web electronic publication. www.fishbase.org, version
  • Kramer, D. E., & Josey, T. (1995). Guide to Northeast Pacific flatfishes: families Bothidae, Cynoglossidae and Pleuronectidae. Sea Grant.

Photos: S. Axtell