Welcome to The Stylet!

Acoela & Nemertodermatida are marine worms within Xenacoelomorpha that occur abundantly among sandy/silty sediments and algae. Most of the species are meiofaunal (a mixed assemblage of small animals that will pass through a 250 µm sieve), with about 400 named acoel species and 9 nemertodermatid species. Most recent studies indicate that they form early branches within Bilateria, making them pivotal to understanding the emergence of complex animals.

The purpose of The Stylet is to provide comprehensive data on the biodiversity and systematics of this group. Specimens are maintained by the Jondelius Lab at the Swedish Museum of Natural History and posted here.