Dehmicyon, Morales & Fejfar & Heizmann & Wagner & Valenciano & Abella, 2021

Morales, Jorge, Fejfar, Oldřich, Heizmann, Elmar, Wagner, Jan, Valenciano, Alberto & Abella, Juan, 2021, The Amphicyoninae (Amphicyonidae, Carnivora, Mammalia) Of The Early Miocene From Tuchořice, The Czech Republic, Fossil Imprint 77 (1), pp. 126-144 : 141-142

Dehmicyon aff. schlosseri ( DEHM, 1950)

Text-figs 1 , 9 , Tab. 1c

L o c a l i t y. Tuchořice, the Czech Republic.

A g e. Early Miocene, MN 3.

S t u d i e d m a t e r i a l. NM-Pv 11675 (TU 738922), right M1; NM-Pv 11676 (TU 738923), right M2.

D e s c r i p t i o n. NM-Pv 11675, right M1 ( Text-fig. 9a 1–4 ). Molar with elongated buccal wall and narrow lingual wall. Well-developed metastyle, separated by a notch from the mesial crista of the metacone. Strong parastyle. Large buccal cingulum. Paracone and metacone subequal in size. Strong pyramidal protocone, surrounded by a prominent cingulum that reaches the bases of both the paracone and the metacone. Reduced paraconule and metaconule, almost completely included in the cingulum.

NM-Pv 11676, right M2 ( Text-fig. 9b ). Small size compared with the M1. Developed parastylar area. Mediumsized parastyle and metastyle. Weak buccal cingulum. Metacone much smaller than the paracone. Protocone in central position which, together with the paraconule and the metaconule, form a semicircle. Strong, wide lingual cingulum.

D i s c u s s i o n. The size of these two molars is similar to that of the homologous teeth of Dehmicyon schlosseri from Wintershof-West described by Dehm (1950) ( Text-fig. 7 ). Features shared with this species: 1) the greater buccal length with respect to the lingual length; 2) the strong development of the buccal cingulum and the buccal styles; 3) the similar paracone-metacone size ratio in the M1; 4) the small size of the M2 compared with the M1. Some of these characters were already pointed out by Peigné and Heizmann (2003) as being typical of D. schlosseri . However, in the morphology of the M1 from Tuchořice there are some differences in relation to this species; in particular, the greater development of the buccal cingulum and the mestastyle are striking; the protocone is placed in a central position, it is robust and surrounded by a very prominent cingulum which reaches the bases of the paracone and metacone, and in which the very reduced paraconule and metaconule are included. The differences in the morphology of the M2 are minor. Taking into account the highly variable dental morphology of most of the amphicyonid species, we classify these two molars from Tuchořice as Dehmicyon aff. schlosseri .

Tribe Magericyonini nov.

T y p e g e n u s. Magericyon PEIGNE, SALESA, ANTON et

MORALES, 2008

D i a g n o s i s. Amphicyoninae with hypercarnivorous dentition; premolars strongly reduced; metaconid reduced or absent in m1 and m2; robust P4; M1 with high buccal cusps; M2⁄m2 reduced relative to M1⁄ m1, M3/m3 vestigial.

I n c l u d e d g e n e r a. Magericyon PEIGNE, SALESA, ANTON et MORALES, 2008 and? Pseudocyon LARTET, 1851

R e m a r k s. Two species are recognized within genus Magericyon – M. anceps PEIGNÉ, SALESA, ANTÓN et MORALES, 2008 and M. castellanus ( GINSBURG, MORALES et SORIA, 1981). Genus Pseudocyon is assigned to this tribe with some doubt.

Figures

Text-fig. 1. Bivariate diagram of length and width of the upper dentition of selected European small and middle size Amphicyoninae compared with the Tuchořice specimens. a: P4; b: M1; c: M2; d: m1; e: m2. Data from Schlosser (1899, 1904), Thenius (1949), Dehm (1950), Heizmann (1973), Ginsburg (1977, 1989), Peigné (2012). Dotted line – ranges of maximum and minimum values from the average of teeth of Cynelos lemanensis from Ulm (Peigné and Heizmann 2003). Abbreviations: L – length; W – width.

Text-fig. 9. Dehmicyon aff. schlosseri (DEHM, 1950), from Tuchořice, the Czech Republic. a: NM-Pv 11675, right M1, a1 – buccal view, a2 – mesial view, a3 – distal view, a4 – occlusal view; b: NM-Pv 11676, right M2 in occlusal view.

Text-fig. 2. Bivariate diagram of length and width of the lower dentition of selected European small and middle size Amphicyoninae compared with the Tuchořice specimens. a: length P4 and M1; b: length m1 and m2; c: length M1 and M2; d: length m1 and p4. Symbols the same as in Text-fig. 1. Data from Schlosser (1899, 1904), Thenius (1949), Dehm (1950), Heizmann (1973), Ginsburg (1989), Peigné (2012). Dotted line – ranges of maximum and minimum values from the average of teeth of Cynelos lemanensis from Ulm (Peigné and Heizmann 2003); solid line – ranges of maximum and minimum values from the average of teeth of Cynelos lemanensis from Saint Gérand (Ginsburg 1977). Abbreviations: L – length.

Text-fig. 3. Paludocyon bohemicus (SCHLOSSER, 1899), from Tuchořice, the Czech Republic, upper teeth. a: NM-Pv 11678, left P4 (paralectotype), a1 – occlusal view, a2 – buccal view, a3 – lingual view, a4 – mesial view; b: NM-Pv 11681, left P4, b1 – occlusal view, b2 – buccal view, b3 – lingual view; c: NM-Pv 11684, left P4, c1 – occlusal view, c2 – buccal view, c3 – lingual view; d: NM- Pv 11685, right M1, d1 – occlusal view, d2 – buccal view; e: NM-Pv 11686, left M1; e1 – occlusal view, e2 – buccal view, e3 – distal view; f: NM-Pv 11687, right M2 in occlusal view; g: NM-Pv 11688, left M2, g1 – buccal view, g2 – occlusal view; h: NM-Pv 11689, right M2 in occlusal view; i: NM-Pv 11690, left M2, i1 – buccal view, i2 – occlusal view; j: NM-Pv 11692, left M3 in occlusal view; k: NM-Pv 11691, right M3 in occlusal view.

Text-fig. 4. Paludocyon bohemicus (SCHLOSSER, 1899), from Tuchořice, the Czech Republic, lower teeth. a: NM-Pv 11677, left m1 (lectotype), a1 – buccal view, a2 – lingual view, a3 – occlusal view; b: NM-Pv 11700, left mandible with c, alveoli for p1–p2, and p3–m2, b1 – occlusal view, b2 – lingual view, b3 – buccal view; c: NM-Pv 11695, right mandible with p2–m2, c1 – lingual view, c2 – buccal view, c3 – occlusal view; d: NM-Pv 11698, right p4–m2, d1 – lingual view, d2 – occlusal view, d3 – buccal view; e: NM-Pv 11697, right p3–m3, e1 – occlusal view, e2 – lingual view; f: NM-Pv 11699, left mandible with p3–m3, f1 – lingual view, f2 – occlusal view, f3 – buccal view; g: NM-Pv 11722, left p4–m3, g1 – buccal view, g2 – lingual view, g3 – occlusal view.

Text-fig. 7. Dehmicyon n. gen. schlosseri (DEHM, 1950), from Wintershof-West, Germany. a: BSP 13562, mandible (holotype), a1 – right hemimandible in buccal view, a2 – occlusal view, a3 – left p4–m2 in occlusal view; b: BSP 12365, left maxilla fragment with M1 in occlusal view; c: BSP 13562, left maxilla fragment with P3 broken, P4–M2 and M3 alveolus (holotype) in occlusal view; d: BSP 12343 left maxilla fragment with P4, alveolus for M1, M2 and M3 alveolus in occlusal view.