Physogaleus is only known from fossil teeth and isolatedvertebra. The teeth are similar to those of the modern Tiger shark, but are smaller, with a more central cusp that projects further from the base of the tooth. The species of Physogaleus were originally described as belonging to the same genus as the modern Tiger shark, Galeocerdo. Recognition of numerous differences in dental anatomy of each of these species compared to other species of Galeocerdo lead researchers to establish the genus Physogaleus to include taxa that were more morphologically similar to one another than they were to Galeocerdo.