Flatfish Flatfish A flatfish is a member of the order Pleuronectiformes of ray-finned demersal fishes, also called the Heterosomata, sometimes classified as a suborder of Perciformes. In many species, both eyes lie on one side of the head, one or the other migrating through or around the head during development. Some species face their left sides upward, some face their right sides upward, and others face either side upward. Many important food fish are in this order, including the flounders, soles, turbot, plaice, and halibut. Some flatfish can camouflage themselves on the ocean floor. Over 700 species are in the 11
RV Platessa in survey logbooks, collected in 1931, 1937, 1946–50, and 1968. These historical measurements have revealed that the ‘sechhi depth’ was much deeper (and therefore water more transparent) in the past compared to today, and thus that the North Sea has become much more turbid. The Suffolk Record Office holds a photograph captioned ""survey ship "Platessa" LT 205 in Lowestoft harbour after being escorted back by the Gorleston lifeboat Khami having sprung a leak whilst working in the Smiths Knoll area"", dated 5th October 1968 (after leaving MAFF service). RV Platessa RV "Platessa" (LT205) was a fisheries research vessel that was