Vasseuromys is a species‐rich genus of small‐ to medium‐sized glirids spanning the latest Oligocene to late Miocene of Europe and western Asia. Despite extensive discoveries over the past 50 years, little phylogenetic work has been done on Vasseuromys. This study presents the first phylogenetic analysis of the genus that includes all the described species and a new taxon Vasseuromys tectus sp. nov. from the late Miocene of eastern Europe, providing the first insights into the evolutionary relationships within the clade. Results suggest that the genus is clearly paraphyletic. Two strongly supported genus‐level clades are recognized within ‘Vasseuromys’: a restricted Vasseuromys clade (containing the three species, V. pannonicus, V. rugosus and V. tectus) and the Glirulus clade that includes ‘Vasseuromys’ duplex. The remaining ‘Vasseuromys’ species are found to constitute a set of paraphyletic taxa, with the polyphyletic ‘Ramys’ nested within it. The genus Gliruloides is synonymized with Glirulus. Vasseuromys tectus sp. nov. is the most derived member of the genus in having a greater number of cheek teeth ridges including constantly present anterotrope, centrotrope, second prototrope on M1–2, third metatrope on M2, two to three posterotropids on p4 and strong ectolophids on lower molars. The results of the study confirm a European origin for Vasseuromys while suggesting that the late Miocene species of the genus dispersed from the east in the early Turolian.
Sinitsa, Nesin, Data Matrix for Gliridae genera
A total of 58 dental characters were scored with all characters equally weighted and treated as unordered. Skeletal characters were not included since cranial and postcranial remains are only known for three extinct taxa, namely G. majori (Vianey-Liaud 1989), V. pannonicus and putative Vasseuromys from St.-Gérand-le-Puy (Vianey-Liaud 1985). The best-known basal glirid Gliravus majori (Stehlin & Schaub, 1951) and primitive leithiine Oligodyromys planus Bahlo, 1975 from the late Rupelian of Heimersheim serving as the outgroup. Apart from V. tectus sp. now. from the late Miocene (late Tortonian) of Palievo in Ukraine the ingroup taxa include all the ten currently recognized species of Vasseuromys. These are: V. autolensis (Cuenca Bescos, 1985) from the early Miocene (early Aquitanian) of Autol 1, Spain; V. bacchius (Martínez-Salanova, 1987) from the early Miocene (late Aquitanian) of Fuenmayor 2, Spain; V. bergasensis Ruiz-Sánchez et al., 2014 from the latest Oligocene (late Chattian) of Bergasa, Spain; V. cristinae Ruiz-Sánchez et al., 2012a from the early Miocene (late Burdigalian) of Pico del Fraile 2, Spain; V. duplex Ünay, 1994 from the early Miocene (late Aquitanian) of Harami 1, Turkey; V. elegans Wu, 1993 from the early Miocene (middle Burdigalian) of Stubersheim 3, Germany; V. pannonicus from the late Miocene (late Tortonian) of Kohfidisch, Austria; V. priscus de Bonis, 1973 from the early Miocene (early Aquitanian) of Moissac 1, France; V. rambliensis Ruiz-Sánchez et al., 2012b from the early Miocene (middle Burdigalian) of Pico del Fraile 1, Spain; and the type species, V. rugosus Baudelot & de Bonis, 1966 from the early Miocene (early Aquitanian) of Laugnac, France. The type species of Ramys, R. multicrestatus (de Bruijn, 1966b) from the early Tortonian of Pedregueras 2A and R. perezi Álvarez-Sierra, 1986 from Ampudia 9 were also included in the analysis to test the monophyly of the concerned genus. Ramys gipanensis Nesin, 2004, a poorly-known species from the middle Tortonian of Mikhailovka 1 was not included in the analysis to minimize the impact of missing data on the present analysis. Microdyromys complicatus de Bruijn, 1966a from the late Langhian of Armantes 7/E and Microdyromys koenigswaldi de Bruijn, 1966a from the early Langhian of Valdemoros 3B/E serve as representatives of basal Glirinae, whereas Peridyromys murinus (Pomel, 1853) from the late Aquitanian of Langy/F serves as representative of basal Seleviniini. Gliruloides zhoui Wu et al., 2016, a putative Vasseuromys-related glirid from the late Oligocene of Tieersihabahe and Saerduoyila assemblages of northern Junggar Basin was included in the analysis to clarify its systematics. The ingroup also includes extant species of Leithiinae (Dryomys nitedula, Myomimus roachi) and Glirinae (Grirulus japonicus) to assess the position of Vasseuromys and some other fossil taxa (Gliruloides, Ramys) with respect to these potentially related genera.
Sinitsa_Nesin_Data_Matrix_for Gliridae_genera.nex
Sinitsa_Nesin_Appendix S1
Characters for phylogenetic analysis.
Sinitsa_Nesin_Appendix S2
Character-taxon matrix used for phylogenetic analysis. A, (01); B, (12); C ,(23)