The world record for the smallest land snail has been broken once again. The minute snail with an average shell diameter of 0.7mm was found in Sabah along with another 47 new species of greatly varying size, by a team of Dutch and Malaysian biologists.
The new tiny snail has been named Acmella nana (nanus is “dwarf” in Latin). The previous title holder, the Chinese Angustopila dominikae which measures just 0.8mm, was just announced a month ago.
Publishing their finds in the journal ZooKeys, the team of snail researchers write that some of the 48 newly described species are widespread in Borneo and have been familiar to them for decades but were only described recently.
Some of the snails eke out a hidden existence on mountain tops or in rare vegetation types and so, were only recently discovered by the authors. For instance, there are seven new species that can only be found on the 4,095m-high Mount Kinabalu. Another example, Diplommatina tylocheilos, only lives at the entrance of the inaccessible Loloposon Cave in Mount Trusmadi.
The new information tells us more about isolated, or endemic snails. Being slow movers, snails are often confined to small patches of a habitat, where they evolve and adapt to the specific site. Their restricted distribution makes them key targets for biodiversity conservation.
“A blazing forest fire at Loloposon Cave could wipe out the entire population of Diplommatina tylocheilos,” says co-author Dr Menno Schilthuizen.
The discoveries are the latest result of an ongoing research project on the snail fauna of Borneo by the authors. For over 25 years, Jaap Vermeulen, Thor-Seng Liew, and Schilthuizen of Naturalis Biodiversity Center and Universiti Malaysia Sabah, have been documenting Malaysia’s terrestrial molluscs. – Pensoft Publishers