The Gold Lyretail Molly, Poecilia sphenops, is a species of freshwater fish (live-bearer) that is closely related to the green swordtail (X. helleri). They make a great addition to a community tank to add a bright splash of gold that is sure to catch your eye. Males and females can be distinguished in a few ways, the main being the presence of a gonopodium (stick shaped reproductive organ). Males will also have a slightly pointed tail (caudal) fin.