Paraphiomys afarensis

Antoñanzas, Raquel López, Sen, Sevket & Mein, Pierre, 2004, Systematics and phylogeny of the cane rats (Rodentia: Thryonomyidae), Zoological Journal of the Linnean Society 142, pp. 423-444 : 430

PARAPHIOMYS AFARENSIS GERAADS, 2001

Geraads (1998: 210) based the new species P. choronensis on two upper molars, two fragmentary upper molars, five fragmentary mandibles, some isolated lower molars, and some incisors, all from the early Upper Miocene Ethiopian locality of Ch’orora ( Geraads, Zeresenay & Hervé, 2002). The holotype of this species is an upper molar (unnumbered) housed in the National Museum of Addis Ababa ( Geraads, 1998: pl. 2, fig. 6). According to Geraads (1998), P. chororensis corresponds to Paraphiomys sp. 2 of Jaeger, Michaux & Sabatier (1980: 371, fig. 3a, b). New material collected at Ch’orora has revealed that the holotype of P. chororensis is actually a P4 of Paraulacodus johanesi . Geraads (2001: 103) has coined the name P. afarensis to accommodate the remaining specimens of the hypodigme of P. chororensis ( Fig. 4G, F). This species has been recently recorded from the Upper Miocene of the lower member of the Nawata Formation, Lothagam, Kenya ( Winkler, 2003).

The morphology of the lower teeth of P. afarensis is close to that of P. shipmani . However, P. shipmani is smaller and its hypolophid is slightly more posteriorly directed. Extrinsic differences such as geographical distribution and age substantiate their distinctiveness, which remains unquestioned to date. One of the differences between P. afarensis and the two species of Paraulacodus rests in the ungrooved upper incisor of the former. The three-lophed lower molars of P. afarensis clearly differ from the four-lophed lower cheek teeth of P. pigotti , P. hopwoodi , Paraphiomys sp. nov. from Saudi Arabia, P. occidentalis , Epiphiomys coryndoni and Sacaresia moyaeponsi . According to Geraads (1998: 210), P. afarensis retains the mesoloph in the upper molars, whereas this structure is absent in the Harasib species P. roessneri and P. australis . Paraphiomys afarensis mainly differs from Apodecter stromeri and P. renelavocati sp. nov. in having the m1 smaller than the m2 and in being more lophodont. It is distinct from Neosciuromys africanus and P. simonsi in being smaller and less hypsodont. Paraphiomys afarensis is larger than the Arrisdrift species P. orangeus .