Simplomys, García-Paredes & Peláez-Campomanes & Álvarez-Sierra, 2009

García-Paredes, Israel, Peláez-Campomanes, Pablo & Álvarez-Sierra, M. Ángeles, 2009, Gliridae (Rodentia, Mammalia) with a simple dental pattern: a new genus and new species from the European Early and Middle Miocene, Zoological Journal of the Linnean Society 157 (3), pp. 622-652 : 627-629

SIMPLOMYS GARCÍA- PAREDES GEN. NOV.

Type species: Pseudodryomys simplicidens De Bruijn, 1966 .

Diagnosis: Small to large-sized Gliridae with simple dental pattern and cheek teeth with moderately concave occlusal surface. The crowns of the cheek teeth are of medium height and the ridges are wide. Premolars are small and very simplified in morphology compared to molars. The upper molars generally consist of the four main ridges only; one centroloph may be present and in some cases even two. Centrolophs are usually not longer than half the width of the occlusal surface. In M1 and M2 the anteroloph ends freely on the lingual side. The protoloph and metaloph are connected before reaching the lingual border, forming an Y-shaped trigon. The lower molars have four or five ridges. If present, the centrolophid is small; its morphology varies from a short prolongation on the anterior lingual border to a well-developed ridge that extends diagonally into the central valley. Its length never exceeds the central axis of the occlusal surface. The mesolophid of the m3 is reduced and does not reach the labial border. The extension of the posterior valley varies from half the width of the occlusal surface to absent.

Differential diagnosis: Simplomys gen. nov. differs from Pseudodryomys De Bruijn, 1966 , Peridyromys Stehlin & Schaub, 1951 , Miodyromys Kretzoi, 1943 , and Prodryomys Mayr, 1979 by its simpler dental pattern and by having relatively smaller and simplified premolars and lower third molars. In Simplomys gen. nov. the mesolophid of the m3 and the p4 is reduced and the posterior valley may be absent.

Simplomys gen. nov. differs from Pseudodryomys and Peridyromys by having a less concave occlusal surface in the upper molars.

0.023 0.052 0.046 0.018

numerical 0.73 0.79 0.75 0.79 0.74 0.84 0.83 0.76 and 0.71 0.75 0.72 0.73 0.70 0.75 0.72 0.72 0.72 0.72 zones local ratio 0.69 0.73 0.71 0.70 0.66 0.69 0.66 0.69 show W

L

/

4 7 4 4 3

10 10 1 1 12 columns 0.146 0.129 0.058 0.094 left 1.46 1.75 1.43 1.63 1.33 1.60 1.35 1.37 second) and

W (L

¥

1.36 1.53 1.38 1.47 1.27 1.43 1.25 1.20 1.31 1.22 First.. bold

area Surface

1.27

4 7

1.38

4

1.28

4

1.36

3

1.25

10

1.23

10

1.18

1 1

1.08

12 deviation locality in standard Type 0.080 0.069 0.045 0.055, SD 1.; Table 1.43 1.55 1.42 1.51 1.37 1.47 1.38 1.41 values see 1.38 1.43 1.39 1.42 1.35 1.38 1.32 1.29 1.35 1.29 maximum localities

.

, of

1.32 1.35 1.31 1.31 1.34 1.25 1.26 1.23 Max

W 4 7 4 4 3 10 10 1 1 13

; values abbreviations

0.044 0.064 0.042 0.038., minimum For. 1999 1.02 1.13 1.01 1.08 0.99 1.14 1.04 0.99 Min., al

0.98 1.06 1.00 1.04 0.94 1.03 0.95 0.93 0.97 0.94 0.94; specimens Daams et 0.96 1.01 0.98 0.99 0.91 0.92 0.89 0.88 of after L 4 8 4 4 3 10 10 1 1 1 12 N

, number localities

Continued VR 3 VR A 1 BB 4 VR 4 A VR 3 SR ART 2 SR SAM OR 2 OR 1 SR1, width; W the) for 2. 16.13 16.14 16.15 16.18 16.35 16.51 16.67 16.70 16.73 16.76 16.78; length My in (Table C B, L ages

Simplomys gen. nov. differs from Prodryomys by having cheek teeth with higher and thicker ridges with slanting walls, as well as narrower valleys.

Simplomys gen. nov. differs from Armantomys De Bruijn, 1966 and Praearmantomys De Bruijn, 1966 by having molars with thinner and lower ridges, by having upper molars with protoloph and metaloph always connected at the lingual half of the occlusal surface forming an Y-shaped trigon. In Simplomys gen. nov. the molars are not progressively smaller from M1/m1 through to M3/m3 as in Armantomys and Praearmantomys .

Simplomys gen. nov. differs from Tempestia Van de Weerd, 1976 by having molars with thinner and lower ridges, M1 and M2 with Y-shaped trigon, m1 and m2 longer than wider and the posterior part of the m3 more reduced and simplified.

Simplomys gen. nov. differs from Altomiramys Díaz Molina & López Martínez, 1979 by having cheek teeth with thicker and slanting ridges and narrower valleys, upper molars with less rounded outline and an anterior valley that does not extend along the lingual border to the protocone.

Etymology: After the simplicity of its dental pattern.

Stratigraphical distribution: Local zones X to E (MN 1, Lower Miocene – MN 5, Middle Miocene).

Geographical distribution: Spain, Portugal, France, Switzerland, and Germany.

Species included

Pseudodryomys simplicidens De Bruijn, 1966 Pseudodryomys robustus De Bruijn, 1967 Pseudodryomys aljaphi Hugueney et al., 1978 Pseudodryomys julii Daams, 1989

Simplomys meulenorum sp. nov.