Crocodiles, alligators, caimans, and gharials are interesting reptiles that have key differences distinguishing them from all other reptiles. These animals can be classified into three families within the order Crocodylia: Alligatoridae (alligators and caimans), Crocodylidae (crocodiles), and Gavialidae (gharials). They are characterized by a long snout with sharp teeth, a long tail, sideways-protruding limbs, a thick scaly ectoderm, and a semi-aquatic, carnivorous lifestyle. As such, they seemingly belong to an apobaramin, separate from all other animals. How many kinds belong to Crocodylia? Are all crocodilian species interrelated, or do they possibly make up multiple, similar-looking kinds, like snakes? No data exists that suggests hybridization between the three crocodylian families therefore morphological analysis is uncertain. However, in this study, the mitochondrial DNA of 19 crocodilians as well as four outliers were aligned, and the species were clustered based on sequence similarity. The current results show a possible split between Alligatoridae and all other crocodilians, suggesting two crocodilian holobaramins. However, other lines of evidence need to be considered. The 37 genes in the mitochondrial genome have virtually the same order in the 19 crocodilians in the study, which may indicate that they are one group. Previous studies suggest three crocodilian holobaramins based on morphological cognita. However, other studies also found a different split between two groups: Alligatoroidea + Crocodyloidea, and Gavialoidea. When fossil species from Eusuchia were added, all of these species were found to form a single holobaramin. Thus, it may be possible that post-Flood extinctions caused the single Crocodylia holobaramin to fragment into subgroups.