Phylogenetic analysis, taxonomic revision, and dental ontogeny of the Cretaceous Zhelestidae (Mammalia: Eutheria)

Abstract

The eutherian, family-level clade Zhelestidae is consistently although weakly supported in five phylogenetic analyses that we performed on all Cretaceous eutherians. Additionally in the fifth analysis, which included some placentals, Zhelestidae is placed as a stem eutherian clade rather than grouping within the crown clade Placentalia as argued in some previous studies but not others. The subfamily Zhelestinae, Dzharakuduk (Turonian -?Coniacian ages), Kyzylkum Desert, Uzbekistan includes Zhelestes temirkayzk, Aspanlestes aptap, Parazhelestes mynbulakensis (=Sorlestes budan), Parazhelestes robustus, Eoungulatum kudukensis. Additional taxa for the time being recognized as Zhelestidae incertae sedis are: Sheikhdzheilia rezvyii (Cenomanian, Uzbekistan), Borisodon kara gen. nov. (='Sorlestes'kara) (Turonian, Kazakhstan), Lainodon orueetxebarriai (Campanian or Maastrichtian, Spain), Labes quintanillensis (Maastrictian, Spain), Labes garimondi (Campanian, France), Gallolestes pachymandibularis (Campanian, Mexico), Gallolestes agujaensis (Campanian, USA), and Avitotherium utahensis (Campanian, USA). Eozhelestes mangit (Cenomanian, Uzbekistan) is a questionable zhelestid (?Zhelestidae), possibly stem to Zhelestidae. Paranyctoides (Asia and North America) is often linked to Zhelestidae. Alostera, previously referred to Zhelestidae, is a eutherian of unknown affinities. Associated skull fragments permitted the first reconstruction of a zhelestid (Aspanlestes) skull. Abundant dentulous and edentulous dentaries allowed examination of dental replacement from the canine posteriorly in Dzharakuduk zhelestids as follows: [dc, p1, dp2, p3, dp4, dp5]->m1->p2->c, p4, m2->p5->m3. © 2012 The Linnean Society of London.