Florida Museum of Natural History

Urocoptid land snails of the genus Holospira from southern Mexico

by Dr. Fred G. Thompson

Holospira is a large genus of land snails that inhabit arid areas of Mexico from Oaxaca north to Texas, New Mexico and Arizona. This study focuses on those species found in the Mexican states of Oaxaca, Puebla and Morelos. Six species described from this area have remained poorly known and enigmatic since their discovery in the mid-19th Century. These were among the earliest known member of Holospira, and their enigmatic status stymied research on the genus. They are redescribed and illustrated, as well as many additional new species from southern Mexico.

Illustration of Holospira

Long, tightly coiled shells are adapted for life in a desert, because their slender shape with a relatively small aperture aids in water retention. Holospirids usually have very small geographic distributions measure in a few miles or less. Some species have a total geographic range of less than 100 meters. A peculiarity of the genus is a complex barrier of lamella within the last two or three whorls. The function of the barrier is that they may prevent arthropod predators from entering the shell.