Gambusia affinis (Mosquitofish) is a species of ray-finned fishes in the family livebearers. They are associated with freshwater habitat. Individuals are known to live for 3 years and can grow to 7 cm.
Definition: length from the tip of the snout to the tip of the longer lobe of the caudal fin, usually measured with the lobes compressed along the midline. It is a straight-line measure, not measured over the curve of the body