Fig. 22From: The oldest described eurypterid: a giant Middle Ordovician (Darriwilian) megalograptid from the Winneshiek Lagerstätte of IowaEvolutionary tree of the major clades of Eurypterina. Stratigraphic ranges of clades are shown by triangles, those of individual genera and species by boxes. Dashed black lines represent inferred ghost ranges. Solid gray lines show the tree topologyBack to article page