Sebecosuchia was first named by Edwin (not Stephen) Colbert for Sebecus and Baurusuchus (Colbert 1946). Turner and Calvo (2005) recognized Stratiotosuchus, Ayllusuchus, Ilchunaia, Bretesuchus, Bergisuchus, Pabwehshi, Iberosuchus, Eremosuchus and their new taxon, Pehuenchesuchus as being sebecosuchians. Their analysis put placed Sebecosuchia as the sistergroup to the taxa we usually would call 'notosuchians' (though technically, the phylogenetic definition of Notosuchia would cover sebecosuchians as well). They did not recognize a distinct division of the Sebecosuchia into two separate clades (e.g. baurusuchids and sebecids), but instead for 'sebecids' to form a paraphyletic assemblage to the Baurusuchidae (incl. Baurusuchus, Pabwehshi, and Bretesuchus).

Larsson and Sues (2007) offered a very different arrangement in which sebecids (represented by Sebecus and Bretesuchus) were the sistergroup to the Peirosauridae forming a clade that they called "Sebecia". "Sebecia" was the sistergroup to the Neosuchia, and Baurusuchus was more basally placed relative to these groups, as was Araripesuchus, and the notosuchians (only represented by Notosuchus and Malawisuchus). They also offered two new phylogenetic definitions for the Sebecidae and the Peirosauridae which would not be very useful in other topologies since both were basically defined to exclude each other (e.g. Sebecidae as Sebecus but not Uberabasuchus or Peirosaurus and Peirosauridae as Uberabasuchus and Peirosaurus but not Sebecus), and in current more global analyses of crocodyliforms (where sebecids are derived members of a clade with notosuchians and peirosaurids are basal neosuchians), it would effectively make all notosuchians to be 'sebecids' and all neosuchians to be 'peirosaurids'. It seems very strange to me that Larsson and Sues (2007) also found Stolokrosuchus (an odd longirostrine form) to be a peirosaurid as well, this taxon is otherwise a basal neosuchian (Turner and Buckley 2008), but more on Stolokrosuchus later...since you can count on more of me giving my two-cents on crocodyliforms to come in the future.

Wargosuchus and Cynodontosuchus are two other baurusuchids which haven't been treated within a phylogenetic analysis to my knowledge, but are both from the Late Cretaceous of Argentina. And of course, there are the three Eocene Venezuelan sebecids... Langstonia, Zulmasuchus, and Barinasuchus. Knowing more about how these taxa really fit in would be good. The same goes for the poorly known trematochampsids for which we have no idea if they have anything to do with sebecosuchians or if they're closer to peirosaurids or something entirely different.

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