Twait shad are silvery, sometimes with a bronzy tinge, and there are a distinctive row of six to ten large dark spot just behind the gill cover though these may fade when the fish is dead. The adult length is typically . The twait shad is found in most of Europe and all countries bordering the Mediterranean Sea. "Alosa fallax" has a similar lifecycle to "A. alosa" (allis shad). They are known to live in sympatry. Some studies have suggested "A. fallax" and "A. alosa" species can hybridize. They are anadromous species, like many other species in the genus "Alosa". However, some
Guinean sea catfish Guinean sea catfish The Guinean sea catfish (Carlarius parkii), also known as the Marine catfish, is a species of sea catfish in the family Ariidae. It was described by Albert Günther in 1864, originally under the genus "Arius". It is a tropical fish which is found in Mauritania, Angola, Morocco and the Spanish Sahara. It inhabits coastal marine waters at a depth range of , also frequently entering estuaries and freshwater rivers. It reaches a maximum total length of , more commonly reaching a TL of . The Guinean sea catfish feeds on bony fish and shrimp. It is of