biostudies-literatureGasiorek PFoundation for Polish SciencePolish Ministry of Science and Higher EducationPolish National Science Centre7606https://www.ebi.ac.uk/biostudies/studies/S-EPMC8027217biostudies-literatureUnknown11(1)Tardigrades constitute a micrometazoan phylum usually considered as taxonomically challenging and therefore difficult for biogeographic analyses. The genus Pseudechiniscus, the second most speciose member of the family Echiniscidae, is commonly regarded as a particularly difficult taxon for studying due to its rarity and homogenous sculpturing of the dorsal plates. Recently, wide geographic ranges for some representatives of this genus and a new hypothesis on the subgeneric classification have been suggested. In order to test these hypotheses, we sequenced 65 Pseudechiniscus populations extracted from samples collected in 19 countries distributed on 5 continents, representing the Neotropical, Afrotropical, Holarctic, and Oriental realms. The deep subdivision of the genus into the cosmopoliScientific reportsPhylogeography and morphological evolution of Pseudechiniscus (Heterotardigrada: Echiniscidae).PMC80272172019/33/N/NZ8/02777DI2015 014945START 28.20202016/22/E/NZ8/00417Voncina KMichalczyk LGasiorek PZajac KfalsePhylogeography and morphological evolution of Pseudechiniscus (Heterotardigrada: Echiniscidae).Tardigrades constitute a micrometazoan phylum usually considered as taxonomically challenging and therefore difficult for biogeographic analyses. The genus Pseudechiniscus, the second most speciose member of the family Echiniscidae, is commonly regarded as a particularly difficult taxon for studying due to its rarity and homogenous sculpturing of the dorsal plates. Recently, wide geographic ranges for some representatives of this genus and a new hypothesis on the subgeneric classification have been suggested. In order to test these hypotheses, we sequenced 65 Pseudechiniscus populations extracted from samples collected in 19 countries distributed on 5 continents, representing the Neotropical, Afrotropical, Holarctic, and Oriental realms. The deep subdivision of the genus into the cosmopoli2021-01-01T00:00:00Z2021 Apr2026-07-16T10:30:43.388Z2026-07-09T10:51:04.113ZS-EPMC80272173382812510.1038/s41598-021-84910-6