Planocrania was subsequently included in the family
Pristichampsidae along with the genus Pristichampsus. Both genera were previously assigned to the
subfamily Pristichampsinae within the family
Crocodylidae before they were placed in their own family, the Pristichampsidae.[5]
However, in a 2013
phylogenetic analysis, the two Asian species of Planocrania were found to be most closely related to the North American and European Boverisuchus, and the family
Planocraniidae was reinstated to contain these genera and replace Pristichampsidae.[6]
Phylogeny
Phylogenetic analyses based purely on
morphological data have generally placed planocraniids in a
basal position within the
crocodiliancrown group. Some of these analyses have found that planocraniids lie just outside
Brevirostres, a group that includes
alligators,
caimans, and
crocodiles but not
gharials.[6][7][8] However, molecular studies using
DNA sequencing have found the group Brevirostres to be invalid upon finding that crocodiles and gavialids are more closely related than alligators.[9][10][11][2][12]
In 2021, Rio & Mannion conducted a new
phylogenetic study using a heavily modified morphological data set, and also noted the lack of consensus and difficulty in placing Planocraniidae. In their study, they recovered Planocraniidae within Crocodylia, as the
sister group to
Longirostres, as shown in the cladogram below:[1]
^
abBrochu, C. A. (2013). "Phylogenetic relationships of Palaeogene ziphodont eusuchians and the status of Pristichampsus Gervais, 1853". Earth and Environmental Science Transactions of the Royal Society of Edinburgh. 103 (3–4): 521–550.
doi:
10.1017/S1755691013000200.
S2CID128920027.