Phylogenetic position of two Macrobiotus species with a revisional note on Macrobiotus sottilei Pilato, Kiosya, Lisi amp; Sabella, 2012 (Tardigrada: Eutardigrada: Macrobiotidae).

In a moss and lichen sample collected on the Polish coast, a new population of Macrobiotus sottilei was found. Given that the original description of M. sottilei was based solely on the morphology observed under light microscopy and measurements of a few individuals, we provide, by means of integrative taxonomy, a revisional note on this species. We present a comprehensive set of morphometric and morphological data from light and scanning electron microscopy analysis together with nucleotide sequences of three nuclear (18S rRNA, 28S rRNA, ITS-2) and one mitochondrial (COI) DNA fragments. We also provide the same set of DNA sequences for Macrobiotus glebkai from a population recently found in Eastern Ukraine and elucidate the phylogenetic position of these two taxa within the family Macrobiotidae. Moreover, the terminology of cuticular bars in macrobiotid legs, and pillars within the egg chorion ornamentation in the Macrobiotus hufelandi morphogroup, are also discussed.