Banff snail

描述：

Description: English: Close-up of a Banff Snail (Physella johnsoni), photo taken in a hot spring pool, Cave & Basin National Historic Site by Paul M. K. Gordon. The snail is approximately 3-5mm in size. Date: 26 October 2006 (original upload date). Source: Transferred from en.wikipedia to Commons by Undead_warrior using CommonsHelper. Author: Paulmkgordon at English Wikipedia.