
Figure 1. Besanosaurus in situ (below) and skull reconstructed (above). Left flippers are reconstructed here from scattered phalanges.
Besanosaurus leptoryhnchus (Dal Sasso and Pinna 1996, Fig. 1) was a large Middle Triassic ichthyosaur with a small skull and slender flippers. The authors nested Besanosaurus between Shonisaurus + Himalayasaurus and Shastasaurinae (Merriamia, Pessosaurus, Californosaurus, Shastasaurus). Unfortunately none of those genera are presently included in the large reptile tree. Besanosaurus nests here (Fig. 2) between Chaohusaurus and Qianichthyosaurus, two taxa not included in Dal Sasso and Pinna. Perhaps over the upcoming weekend more ichthyosaurs can be added to the large reptile tree. We nested Mikadocephalus at the base of the ichthyosaurs recently here.
Below are a series of ichthyosaur skulls to show how Besanosaurus nests with them. Gray bones below Besanosaurus may be hyoids.
The original identification of the skull bones is shown below (Fig. 4). A few changes were made here (Fig. 1).
References
Dal Sasso C and Pinna G 1996. Besanosaurus leptorhynchus n. gen. n. sp., a new shastasaurid ichthyosaur from the Middle Triassic of Besano (Lombardy, N. Italy). Paleontologia Lombardia 4:23 pp.