- The Sonoyta Mud Turtle is a dark-colored freshwater reptile with webbed feet, mottled skin, and an olive brown shell - It gets its name from the Rio Sonoyta, its native watershed along the US -Mexico border - The pond at Quitobaquito Springs, a desert oasis at Organ Pipe Cactus National Monument in southwestern Pima County, is the only place in the US where the endangered Sonoyta Mud Turtle can be found ... MAP - The Arizona-Sonora Desert Museum (ASDM) west of Tucson has been harboring members of the species since 2007 and was the first facility to successfully breed the animals in captivity ... MAP - The so-called “assurance population” at ASDM now stands at more than 50, including the original turtles first brought there 18 years ago