Chasmataspidida is an order of peculiar arthropods, which seem to resemble both xiphosurans and eurypterids. Their phylogenetic placement is still very uncertain because of this. Therefore, I decided to learn more about these creatures in order to see if I would be able to come up with my own hypothesis regarding their phylogenetic placement. Chasmataspidida consists of two clades: Chasmataspididae (one genus) and Diploaspididae (10 genera). I decided to focus on Chasmataspididae first. The only genus in Chasmataspididae is Chasmataspis . It was first described by Caster and Brooks, and later redescribed by Dunlop et al. Reconstruction of Chasmataspis according to Caster and Brooks. Something that sets Chasmataspidids apart from Eurypterids is the clear separation of the carapace, abdomen and postabdomen, making them resemble Xiphosurans a lot more. Reconstruction of Chasmataspis by Dunlop et al. Dunlop et al. noted that Chasmataspis would have likely h
This is not the age of mammals; it has always been the age of arthropods