Two species groups can be distinguished in the evolution of Pseudolioceras s.l. The first ranges through most of the Toarcian (and? earliest Aalenian) and makes up the circum-Boreal Pseudolioceras s.s. The second extends through the Aalenian and earliest Bajocian of the Bering Province and constitutes the subgenus Tugurites, of considerable chronostratigraphic importance.

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