The Eastern Mosquitofish (Gambusia holbrooki ) is a species of freshwater fish, closely related to the western mosquitofish (Gambusia affinis ). Mosquitofish (Gambusia affinis) is an example of a freshwater fish species whose remarkable diffusion outside its native range has led to it being placed on the list of the world’s hundred worst invasive alien species (International Union for Conservation of Nature). Eastern gambusia are now common in NSW waters and throughout Victoria, Queensland, Western and South Australian waterways. Other names include Plague Minnow and Eastern Gambusia. “Introduction of the western mosquitofish into northern California occurred in 1922 when 600 G. affinis were planted in Fort Sutter lily pond. Native to the Eastern and Southern United States from Florida to Pennsylvania and inland to Alabama and Tennessee. Mosquitofish are planted because they eat crustaceans and insects on or near the water's surface, including a high number of mosquito larvae when available. I strongly encourage anyone else who can help with any other ID tips here and also with regards to the Eastern Mosquitofish vs. the Western Mosquitofish. I would just like to validate some lifelist species of mine here. Members of this population were then introduced into the vicinities of Glenn, Kern, Coachella Valley, and Los Angeles CA during the 1920s and They are both small freshwater fish that give birth to live young and are not above cannibalizing them. Male mosquitofish have an elongated anal fin (gonopodium) used for internal fertilization whose formation is driven by androgens. Western mosquitofish use the same habitat as the plains topminnow Fundulus sciadicus and have displaced these topminnows and other species with their aggressive behavior (Whitmore 1997). There are actually two species of mosquitofish, with the western mosquitofish more commonly available for sale, and the eastern mosquitofish (G. Holbooki) almost never being found in fish stores. Native to the Eastern and Southern United States from Florida to Pennsylvania and inland to Alabama and Tennessee. But this article is mainly about gambusia affinis. This is some basic info for keeping and breeding mosquitofish or gambusia. The mosquitofish is also responsible for the elimination of the least chub Iotichthys phlegethontis. Other names include Plague Minnow and Eastern Gambusia. Its reputation as a mosquito eater is responsible for one of its common names, Mosquitofish. Feral Guppy vs. Mosquitofish I would just like to validate some lifelist species of mine here. Eastern Mosquitofish (Gambusia holbrooki). The figure to the left … The north end of its range is located from New Jersey down through the eastern portion of the Atlantic seaboard reaching as far west as southern Alabama (Boschung and Mayden 2004; Page and Burr 2011). It is a member of the family Poeciliidae of order Cyprinodontiformes. Members of this population were then introduced into the vicinities of Glenn, Kern, Coachella Valley, and Los Angeles CA during the 1920s and 1930s. The Eastern Mosquitofish is an invasive species of freshwater fish and a member of the Poeciliidae family. Rate of cannibalism was 1%. The Eastern and Western mosquitofish (Gambusia holbrooki and G. affinis) are potential bioindicator organisms for endocrine disruptors. I think I have both of these species, however I don't have any males with them (expect melanistic Eastern male). The Eastern Mosquitofish (Gambusia holbrooki ) is a species of freshwater fish, closely related to the western mosquitofish (Gambusia affinis ). I chose female guppies and male western mosquitofish because of a study which showed successful crosses between male western mosquitofish and female eastern mosquitofish, but failed to show successful crosses of the reverse genders due to what is essentially a killer sex chromosome (reference 1).