Lomasuchus had a deep, narrow snout characteristic of peirosaurids. The serrated teeth were compressed, although not to the extent seen in other related genera such as Peirosaurus. Many similarities can be seen between its morphology and that of the related Uberabasuchus, such as the narrow snout and a groove at the maxilla-premaxilla contact that accommodated for an enlarged fourth mandibular tooth. The two genera are distinguished from one another on the basis of several features, including the shape of the orbits.[4]
Lomasuchus lends its name to a subfamily of peirosaurids called the Lomasuchinae. Lomasuchinae was constructed in 2004 and included Lomasuchus (the type genus), and a tribe called Mahajangasuchini, which included Mahajangasuchus and Uberabasuchus. Mahajangasuchus is now placed outside Peirosauridae in a different family, Mahajangasuchidae.[4]
^Diego Pol & Zulma Brandoni de Gasparini (2007). "Crocodyliformes". In: Patagonian Mesozoic Reptiles. Gasparini, Z., Coria, R., & Salgado, L. (Eds.). Indiana University Press: 116–142.