New Records of Antarctic Tardigrada with Comments on Interpopulation Variability of the <i>Paramacrobiotus fairbanksi</i> Schill, Förster, Dandekar and Wolf, 2010

• Main Authors: Łukasz Kaczmarek, Monika Mioduchowska, Uroš Kačarević, Katarzyna Kubska, Ivan Parnikoza, Bartłomiej Gołdyn, Milena Roszkowska
• Format: Article
• Language: English
• Published: MDPI AG 2020-03-01
• Series: Diversity
• Subjects: cosmopolitism; dispersal; zoogeography; “everything is everywhere” hypothesis, fauna; water bears
• Online Access: https://www.mdpi.com/1424-2818/12/3/108

Studies on Antarctic tardigrades started at the beginning of the twentieth century and have progressed very slowly and ca. 75 tardigrade species are known from this region. <i>Paramacrobiotus fairbanksi</i> was described from USA based on genetic markers and later reported from Italy, Poland, and Spain. The &#8220;everything is everywhere&#8221; hypothesis suggests that microscopic organisms have specific features which help them to inhabit most of environments and due to this they can be considered cosmopolitan. In the present paper, we report eight tardigrade taxa from Antarctic, including the first report of <i>Pam. fairbanksi</i> from Southern Hemisphere, which could suggest that the &#8220;everything is everywhere&#8221; hypothesis could be true, at least for some tardigrade species. Moreover, we also genetically and morphologically compare a few different populations of <i>Pam. fairbanksi</i>. The p-distances between COI haplotypes of all sequenced <i>Pam. fairbanksi</i> populations from Antarctica, Italy, Spain, USA and Poland ranged from 0.002% to 0.005%. In the case of COI polymorphism analyses, only one haplotype was observed in populations from Antarctica, USA and Poland, two haplotypes were found in population from Spain, and six haplotypes were observed in population from Italy. We also found some statistically significant morphometrical differences between the populations of <i>Pam. fairbanksi</i> from different regions and designed a new specific primers for <i>Paramacrobiotus</i> taxa.