Pyctis inamatus Babbitt, 1999

WANG, XIAOMING, McKENNA, MALCOLM C. & DASHZEVEG, DEMBERELYIN, 2005, Amphicticeps and Amphicynodon (Arctoidea, Carnivora) from Hsanda Gol Formation, Central Mongolia and Phylogeny of Basal Arctoids with Comments on Zoogeography, American Museum Novitates 3483, pp. 1-58 : 39-41

Pyctis inamatus Babbitt, 1999

COMMENTS: Pyctis inamatus was named on the basis of a left jaw fragment with p3 (broken)–m1 and partial m2 alveolus from the Tatal Gol area in a ‘‘red claystone unit, SW of Maikant, 16.9 m above the lava layer in the Shand Member’’ ( Babbitt, 1999: 791). With an m1 length of approximately 11 mm, Pyctis is somewhat smaller than Amphicticeps makhchinus (arctoids tend to have a somewhat shorter P4 than m1; the reverse is true between Pyctis and A. makhchinus ) but falls in the range of A. dorog (see measurements in tables 3, 5). Pyctis is highly hypercarnivorous with an extremely trenchant m1 talonid, which has a single, centrally located hypoconid, along with the complete loss of m1 metaconid. This dental pattern is almost exactly opposite to that in A. makhchinus , which tends toward the hypocarnivorous direction. Pyctis is also more hypercarnivorous than A. dorog , which still retains a substantial m1 metaconid and entoconid. Another important difference between A. dorog and Pyctis is the presence of a posterior accessory cusp on the p4 of the former, which is lacking in the latter.

Babbitt (1999) compared Pyctis with some basal mustelids from the early Miocene of Europe, such as Plesiogale and Paragale , and she also made comparisons with later Eurasian forms, such as Eomellivora and Mellivora . Given the poor condition of the holotype, she did not draw definitive systematic conclusions, except placing it in the family Mustelidae .

Pyctis also shares some resemblance to certain oligobunines (a group of basal musteloids) in the late Oligocene through early Miocene of North America ( Baskin, 1998a), such as Oligobunis and Megalictis , which also have a highly hypercarnivorous lower carnassial and reduced posterior accessory cusp on p4. On the other hand, Ischyrictis and Hoplictis from early to middle Miocene of Europe also exhibit tendencies toward hypercarnivory ( Ginsburg and Morales, 1992). The systematic status of Pyctis will remain uncertain without additional materials, particularly its upper teeth.