The upper temporal fenestrae are large, possibly indicating a strong bite force despite its lack of teeth.

The ribcage is deepest at the shoulders and gradually becomes shallower, forming a straight, constant slope, similar to Cartorhynchus but in contrast to the more rounded underside seen in other ichthyosauromorphs.

The haemal arches possess a unique morphology, where only the ninth pair and onwards are fused distally, however unlike other diapsids they are not V- or Y-shaped in cranial view, but U-shaped.

[1] In the phylogenetic analysis performed by Jiang et al. 2016, Sclerocormus was found to be a basal ichthyosaurform and as a sister taxon to Cartorhynchus.

Jiang et al. erected the new clade Nasorostra ('nose beak') for these two taxa, itself a sister taxon to Ichthyopterygia.

[1] Due to the small size of its jaws and head relative to its body, Sclerocormus would have been limited to feeding on prey much smaller than itself.