What is known about the fossil branchiopod Lepidocaris rhyniensis?

Lepidocaris rhyniensis is a minute, extinct branchiopod from the Devonian period, discovered in the Rhynie cherts of Scotland. It is the sole member of the order Lipostraca.12

Because of its exceptional preservation, Lepidocaris is the best-known fossil crustacean, allowing scientists to determine its anatomy and feeding habits with high precision. Key features include:1

• Structure: It lacked a carapace and possessed 13 pairs of trunk limbs, along with a pair of large antennae likely used for swimming.2
• Feeding: The first three pairs of trunk limbs were adapted to scrape material from surfaces, such as plants or stones. Setae near the limb bases then transported this food forward to the mouth.1
• Locomotion: The trunk limbs located behind the first three pairs were two-branched and functioned as swimming appendages.1

This level of detail is unique among fossil branchiopods, as many other species from the same era are known only from their carapaces.1