Abstract:
The genus Propotamochoerus has been recorded for the first time from the Nagri formation of the Middle Siwaliks of Pakistan. Among the subfamily suinae, the genus Propotamochoerus was abundantly present in the Dhokpathan formation. The early Propotamochoeroides were very close to the Palaeochoerus and were considered to be the ancestors of other suinae. Three major groups evolved from early Propotamochoeroid stock, one leading to genera Potamochoerus and Sus, and the other to the genera Hippohyus, Sivahyus and still other to the genera Microstonyx, Hippopotamodon and Jhelumia. In the first line, the cheek teeth remained bunodont with the development of accessory tubercles due to which the crown became much complicated; in the second line, there was a trend towards elongations of the cusps while in the third line, the major trend was the attainment of gigantic size. Propotamochoerus hysudricus differs from the other species due to the dental morphology of premolars. It shows admixture of primitive and advanced characters of Propotamochoerus and Potamochoerus. There are several trends to be discerned in the material such as variation in size, complexity and hypsodonty of the premolars, and change in enamel thickness of the molars. It is suggested that Propotamochoerus evolved from Hyotherium during Chinji times about 11 million years ago.
Page(s):
17-32
DOI:
DOI not available
Published:
Journal: Biologia, Volume: 54, Issue: 1, Year: 2008