The Siberian tardigrade fossils differ from living tardigrades in several ways. Echiniscus testudo is a cosmopolitan species of tardigrade. Lobopodian taxa of tardigrade stem-group is unclear. Milnesium swolenskyi is a species of tardigrade from the Cretaceous period. Mopsechiniscus franciscae is a species of tardigrade native to Antarctica. Tardigrade fossils go as far back as the Cretaceous period in North America. Tardigrade genomes vary in size, from about 75 to 800 megabase pairs of DNA. Biologists have a difficult time finding verification among tardigrade species because of this relationship. Parachaela is an order of tardigrade in the class Eutardigrada. Macrobiotus shonaicus () is a species of tardigrade in the family Macrobiotidae. Macrobiotus is a genus of tardigrade consisting of about 100 species. In 2018, the tardigrade advanced several rounds without winning. In this cryptobiotic state, the tardigrade is known as a tun. Four families, nine genera and 21 species of Tardigrade were found in the Palace. Paradoxipus orzeliscoides is a species of tardigrade.