Loricifera is a phylum of very small to microscopic marine cycloneuralian sediment-dwelling animals that had been determined to be 37 described species, in 9 genera, but in 2021 has increased to 43 species. Aside from these described species, there are approximately 100 more that have been collected and not yet described. Their sizes range from 100 μm to ca. 1 mm.
Reinhardt Møbjerg Kristensen is a Danish invertebrate biologist, noted for the discovery of three new phyla of microscopic animals: the Loricifera in 1983, the Cycliophora in 1995, and the Micrognathozoa in 2000. He is also considered one of the world's leading experts on tardigrades. His recent field of work revolves mostly around arctic biology.
Pliciloricidae are a family of marine organisms in the phylum Loricifera. It contains 23 species in 4 genera.
Rugiloricus is a genus of marine organisms of the phylum Loricifera and the family Pliciloricidae, described by Higgins & Kristensen in 1986.
Arthrotardigrada are an order of tardigrades, first described by Marcus in 1927. It consists of the following families:
Echiniscoidea are an order of tardigrades, a phylum of water-dwelling, eight-legged, segmented micro-animals. It was first described by Richters in 1926.
Batillipes is genus of tardigrades, the only genus in the family Batillipedidae. It was first described by Ferdinand Richters in 1909.
The Styraconyxidae are a family of tardigrades. The family was first described by Reinhardt Møbjerg Kristensen and Jeanne Renaud-Mornant in 1983.
Renaudarctus is a genus of tardigrades in the family Renaudarctidae. The genus was first described by Reinhardt Kristensen and Robert P. Higgins in 1984, and named after biologist Jeanne Renaud-Mornant.
The Tanarctidae are a family of tardigrades. The family was named and described by Reinhardt Møbjerg Kristensen and Jeanne Renaud-Mornant in 1980.
Faeroestygarctus dezioae is a species of armoured marine tardigrades. It is the only species of Faroestygarctus, a genus of the family Stygarctidae.
Proechiniscus hanneae is a species of tardigrade. It is the only species of Proechiniscus, a genus within the family Echiniscidae.
Echiniscoides is a genus of tardigrades in the family Echiniscoididae. It was named and described by Ludwig Hermann Plate in 1888.
Novechiniscus armadilloides is a species of terrestrial tardigrade. It is the only species of the genus Novechiniscus, which belongs to the family Echiniscidae. The species is endemic to the United States in the state of Utah.
Wingstrandarctus is a genus of tardigrades, in the subfamily Florarctinae which is part of the family Halechiniscidae. The genus was named and described by Kristensen in 1984.
Tanarctus is a genus of tardigrades in the family Tanarctidae, named and described by Jeanne Renaud-Debyser in 1959.
Raiarctus is a genus of tardigrades in the family Styraconyxidae. The genus was named and first described by Jeanne Renaud-Mornant in 1981.
Tholoarctus is a genus of tardigrades in the family Styraconyxidae. The genus was named and first described by Kristensen and Renaud-Mornant in 1983.
Macrobiotidae is a family of tardigrade. As of 2017, it consists of the following genera:
