Genus Fundulus refers to a group of small North American fish commonly called killifish. These fish are significant to freshwater and marine ecosystems, as they serve as prey for larger fish and birds. There are various synonyms for Genus Fundulus, including Cyprinodon, Fundulopanchax, Jordanella, and Leptolucania, among others. These synonyms are used to categorize and differentiate the different species that belong to the Genus Fundulus. Some of the popular killifish species within this genus include the mummichog, the striped killifish, and the Gulf killifish. Killifish enthusiasts and researchers must understand these synonyms to accurately identify and study these fascinating fish.