Fossil evidence of this genus is principally found in the Karoo Basin of South Africa, in the Dicynodon Assemblage Zone.

[1] Lack of fossil record after the Late Permian epoch suggests that Pelanomodon fell victim to the Permian-Triassic extinction event.

[2] The Karoo Basin during this period was characterized by its extensive flood plains,[3] so to hypothesize a mud based habitat for this genus is not far fetched.

Aulacephalodon is believed to have lived alongside Pelanomodon in the Karoo Basin, where as records of Geikia have been discovered in Scotland and Tanzania.

The absence of tusks is a significant feature that is used to differentiate Pelanomodon from Aulacephalodon, in addition to bosses on the post orbital bar and twisting of the zygoma.

[1] Pelanomodon is distinguished from Geikia due to its longer temporal fenestra and snout, lesser developed oesophageal crest and flush pineal foramen.

[1] The same analysis claims that Propelanomodon, another tuskless dicynodont genus, first described by Broom in 1913,[4] is in fact a juvenile form of Pelanomodon.

[1] Two species have been previously classified, Pelanomodon moschops (P. moschops), identified by having a skull longer than 18 cm in length and relatively small cranial bosses and Pelanomodon rubidgei (P. rubidgei), identified by having a skull longer than 18 cm but with relatively large cranial bosses.

Several key cranial features differ within this species when compared to P. moschops’ skulls, which leaves there to be debate among paleontologists about its relationship to Pelanomodon.

[5] This combined with some of the other cranial features described above, such as the placement of the nares and orbit, suggests that the animal may have consumed plants from shallow waters.

Sedimentary analysis suggests that during this time the region was characterized by the extensive flood plains of a few large rivers.

[10] This climate, combined with the important role that rivers played in establishing the environment, allowed for a variety of riparian vegetation to grow, which in turn lead to a high diversity of animals that were all able to fill a different niche.