A new species of the live-bearing fish genus Poeciliopsis from northern Mexico (Cyprinodontiformes, Poeciliidae) October 31, 2019 by Lindsay Hutchins WFSC TAMU/MBARI team use a combination of genetics and skeletal anatomy to describe new species of livebearing fish microendemic to the Rio Concepcion in Sonora: the Rio Concepcion Topminnow (Poeciliopsis jackschultzi). Read. News article