Animas Mountains Holospira Snail (Holospira animasensis) is a small (shell length 3.7 mm) terrestrial snail that is only known from the north slope of a single hill at the north end of the Animas Mountains in Hidalgo County, New Mexico. They live at an elevation of 1,500-1,825 m in limestone outcrops of a hill that is characterized by grassy scrub.