Just when you thought snails couldn’t get any smaller…

World record broken in just over a month

LATEST IN LITTLEST A drawing shows the form of a newly named snail species, Borneo’s Acmella nana. These snails are so tiny, their shells fit between the letters of the journal article that describes them.

Menno Schilthuizen/NATURALIS BIODIVERSITY CENTER

Tiny, meet tiniest. The record for the world’s smallest known snail has been broken just over a month after its announcement. The latest champ: A new species a full 0.3 millimeters smaller.

The new winner is a mere pinhead of a gastropod named Acmella nana. Found in Borneo, it grows a shell 0.50 to 0.60 millimeters in diameter, an international research team reports November 2 in ZooKeys.

Its white shell has “some nice spiral lines,” but otherwise it’s not the most spectacular looking of Malaysian snails, says codescriber Menno Schilthuizen of Naturalis Biodiversity Center and Leiden University in the Netherlands. He and his colleagues gave the snail its formal name (meaning “dwarf” in Latin) based on the discovery of empty shells. Researchers suspect the   animals live in limestone caves.

The previous record holder for smallest snail was Angustopila dominikae from China, described September 28. 

Susan Milius is the life sciences writer, covering organismal biology and evolution, and has a special passion for plants, fungi and invertebrates. She studied biology and English literature.