About Glyptostoma gabrielense Pilsbry, 1938
Glyptostoma gabrielense is a medium-sized snail species. Its flattened, disk-like shell is approximately 30 millimeters (1.2 inches) across and 14 millimeters (0.55 inches) high. The shell is dark chestnut brown, and the snail’s body is dark gray. This species is native to a 15-mile (24-kilometer) long narrow strip of the front range of the San Gabriel Mountains near Pasadena, California. It lives in riparian canyons and other areas with enough seasonal moisture. Historically, it also occurred in the Dominguez Hills to the south, but this population is now extirpated. Before extensive development and habitat clearing in the lower elevations of the San Gabriel Valley, the species was likely also found there. The small range that Glyptostoma gabrielense occupies is part of the California Floristic Province, so its habitat has a Mediterranean climate with extremely dry summers that see almost no precipitation. During cool months when conditions are wet, G. gabrielense can move across the surface. During the dry season, which typically runs from June through October, this species aestivates underground. Like other snails in the genus Glyptostoma, G. gabrielense feeds on decomposing plant material, along with the fungi and bacteria that are part of the decomposition process.
