Macrobiotus muralis, Bertolani & Cesari & Giovannini & Rebecchi & Guidetti & Kaczmarek & Pilato, 2023

Bertolani, Roberto, Cesari, Michele, Giovannini, Ilaria, Rebecchi, Lorena, Guidetti, Roberto, Kaczmarek, Łukasz & Pilato, Giovanni, 2023, The Macrobiotus persimilis-polonicus complex (Eutardigrada, Macrobiotidae), another example of problematic species identification, with the description of four new species, Organisms Diversity & Evolution (New York, N. Y.) 23 (2), pp. 329-368 : 364

Macrobiotus muralis sp. nov. differs from:

Macrobiotus persimilis by: having shorter placoids (see Tables 4 and 7), less evident teeth on the lunules of the hind legs and eggs with barely visible dots around the egg processes.

Macrobiotus hyperboreus by: having eyes, presence of indented lunules on the hind legs, presence of males with a lateral gibbosity on each hind leg, presence of weak dots around the egg processes and absence of plates on the distal discs of the egg processes.

Macrobiotus polonic us by: having shorter egg processes (see Table 5), with a small neck and a distal discs with small depressions.

Macrobiotus marlenae by: having stylet supports inserted more posteriorly (pt mean 77.6 ± 0.9 in M. muralis sp. nov. vs 79.7 ± 0.7 in M. marlenae ), longer placoids row (pt mean 59.7 ± 1.2 in M. muralis sp. nov. vs 50.8 ± 3.3 in M. marlenae ), a larger number of egg processes on the circumference (24–32 in M. muralis sp. nov. vs ca. 16 in M. marlenae ) and distal discs more similar to gear wheels than stars.

Macrobiotus trunovae by: smaller body length (up to 412 µm in length vs. up to 639 µm in M. trunovae ), smaller eggs without processes (73–76 µm in diameter in M. muralis sp. nov. vs 134.3 µm in M. trunovae ), a more anterior insertion of the stylet supports (pt 77.6 in M. muralis sp. nov. vs 82.4 in M. trunovae ), longer claws (pt external claw of the II-III pair 31.3–34.7 in M. muralis vs 25.6 in M. trunovae ) smaller egg processes (up to 10.9 µm in height in M. muralis vs. up to 4.8 µm in M. trunovae ) and lower number of egg processes on the circumference (25–29 in M. muralis vs 32 in M. trunovae ).

Macrobiotus anemone by: the presence of eyes, presence of granulation on the hind legs, presence of a posterior band of teeth in the buccal armature, presence of indented lunules on the hind legs and egg processes with indented discs instead of tentacular distal discs.

Macrobiotus halophilus by: having clearly unfused transverse dorsal ridges in the buccal armature (almost fused in M. halophilus ), absence of granulation on the first three pairs of legs, lower number of processes on the egg circumference (up to 29 in M. muralis sp. nov. vs. up to 36 in M. halophilus ) with indentation of the distal discs less marked (clearly less than 1 µm vs. 0.9–1.4 µm in M. halophilus ).

Macrobiotus dolosus sp. nov. by: having longer placoids and claws (see Tables 6 and 7), egg processes with neck and with a small depression in the distal discs.

Macrobiotus siderophilus sp. nov. by: having shorter and more stocky egg processes, with a larger and inflexible distal discs (see Table 5).

Macrobiotus fontourai sp. nov. by: having a more evident constriction in the first macroplacoid and smaller egg processes (see Table 5) situated more distant from each other, with shorter teeth on the distal discs, with poorly visible neck and indistinct dots around the egg processes.