Plectus_parvus
Plectus parvus
Species of freshwater and terrestrial roundworm
Plectus parvus is a species of nematode (roundworm) found in freshwater and terrestrial environments. It has been sampled in Europe and New Zealand.[1] Along with the similar nematode Panagrolaimus detritophagus, in 2018 it was the first species of multicellular eukaryote to be thawed into a living state after prolonged cryopreservation. Female worms of this species were found in Pleistocene permafrost in the Kolyma River lowland (one of the sites was near the Alazeya River).[2] They were mobile and ate, after being frozen for 30–40 thousand years.[3][4]