The diamond killifish (Fundulus xenicus) is a species of North American killifish found in salt marshes, hypersaline flats and mangrove along the Gulf Coast of the United States. This species grows to a length of 6cm (02inches). It is found in the aquarium trade. It was previously recognized as, Adinia xenica, the only known member of the genus Adinia. Nucleotide analyses has reevaluated the phylogeny of the Funduliidae and placed the diamond killifish into the Fundulus genus.[1]