Pleuronectidae and they sink to the bottom. They are found on the bottoms of oceans around the world, with some species, such as the Atlantic halibut, "Hippoglossus hippoglossus", being found down to . The smaller species eat sea-floor invertebrates such as polychaetes and crustaceans, but the larger righteye flounders, such as "H. hippoglossus", which grows up to in length, feed on other fishes and cephalopods, as well. They include many important commercially fished species, including not only the various fish called flounders, but also the European plaice, the halibuts, the lemon sole, the common dab, the Pacific Dover sole, and the
Flat needlefish the left gonad in both sexes is developed, and in males, the right gonad is sometimes wholly absent. Flat needlefish The flat needlefish ("Ablennes hians"), the only known member of the genus Ablennes, is a marine fish of the family Belonidae. Flat needlefish are considered gamefish, frequently caught with the help of artificial lights, but are not often eaten because of their green-colored flesh. The generic name "Ablennes" – formerly misspelled "Athlennes" – means ‘without ’, from the ancient Greek privative "a-" prefix and "blennos" (‘mucus’). Its specific name is Latin for "gaping". Although they have no spines, they do