Fig. 3 in The Macrobiotus persimilis-polonicus complex (Eutardigrada, Macrobiotidae), another example of problematic species identification, with the description of four new species

Fig. 3 Male specimens of the Macrobiotus persimilispolonicus complex. a Spermatozoa within the testis (Osimo, Italy, orcein DIC); b spermatozoa (arrows) and spermatids (arrowheads) within the testis (Osimo, Italy, orcein PhC); c spermatozoa (arrows) and spermatids (arrowheads) within the testis (Paris, France, orcein PhC); d spermatozoa (arrow) and spermatids (arrowhead) within the testis (Novellara, Italy, orcein PhC)