The crocodile shark, Pseudocarcharias kamoharai, is a small lamniform shark that occupies tropical oceans worldwide. Here, its cranial musculature and ligaments associated with jaw suspension are described in detail for the first time. Anatomical data extracted from this study is combined with data from existing literature, and mapped onto previously proposed phylogenetic trees examining the evolutionary pattern of jaw morphology through lamniform phylogeny. Results show that the evolution of characters associated with jaw suspension is more parsimonious in the morphology-based phylogenetic tree than in the molecular-based tree. Additionally, the evolutionary scenario of lamniform jaws is found to be more complex than previously hypothesized regardless of the tree used.
Achebe, Ikechukwu B.
"Cranial Musculature in Extant Crocodile Shark, Pseudocarcharias kamoharai (Lamniformes: Pseudocarchariidae) and its Evolutionary Implications,"
DePaul Discoveries: Vol. 1
, Article 5.
Available at: http://via.library.depaul.edu/depaul-disc/vol1/iss1/5