Heterocricetodon gaimersheimensis Freudenberg, 1941

Vianey-Liaud, Monique, Comte, Bernard, Marandat, Bernard, Peigné, Stéphane, Rage, Jean-Claude & Sudre, Jean, 2014, A new early Late Oligocene (MP 26) continental vertebrate fauna from Saint-Privat-des-Vieux (Alès Basin, Gard, Southern France), Geodiversitas 36 (4), pp. 565-622 : 598-600

Heterocricetodon gaimersheimensis Freudenberg, 1941

( Fig. 12 )

HOLOTYPE. — Fragment of right lower jaw, bearing m1-3, BSP 1939 XI 4, BSPG, Munich.

TYPE LOCALITY. — Gaimersheim (South Germany), MP 27-28.

ORIGINAL DIAGNOSIS. — See Freudenberg (1941: 105). Description and variability of teeth of the type-population: Kristkoiz (1992: 63-72).

MEASUREMENTS (in mm). — Eight isolated teeth: 1 M1

(2.54 × 1.66), 3 M2 (2.12 × 1.94, 2.17 × 1.86, 1.94 × 1.79), 1 M3 (1.72 × 1.54), 1 m 1 (2.65 × 1.60), 1 m 2 (2.54 × 1.47), 1 m 3 (2.37 × 1.78).

DESCRIPTION

M1. Ŋe anterior arm of the protocone and the mesoloph join the labial edge of the tooth, like on several specimens from Gaimersheim.

M2-M3. Ŋere is a double connecting of the anterior cusps (complete metalophule I and II) and the mesoloph reaches the labial edge of the teeth, as it happens on some specimens from Gaimersheim.

m1. Ŋe two mesolophids are short, like it is often the case in the type population.

m2. Ŋe posterior arm of the protoconid is short but exceeds the mesolophid length, extending towards the metaconid, as for some specimens from Gaimersheim.

m3. Ŋe posterior arm of the protoconid is long and joins the labial edge of the tooth, at the base of the metaconid ridge.

DISCUSSION

Four species of relatively large size have been referred to this genus. Among them, H. stehlini Schaub, 1925 , H. schlosseri ( Schaub, 1925) and H. helbingi Stehlin & Schaub, 1951 , remain poorly defined. Hugueney (1980), in her discussion about the species of Heterocricetodon from Saint-Menoux, has suggested that the variations between the three species stehlini , schlosseri and helbingi could enter a unique species, when more material would be known. Concerning H. gaimersheimensis Freudenberg, 1941 , Engesser (1987) supposed that “the material from Gaimersheim described by Freudenberg includes two species, H. stehlini and H. helbingi ”. Later, an extensive study has been achieved by Kristkoiz (1992). He established the presence of only one species although with a great variability in the abundant material from Gaimersheim. Ŋerefore, H. stehlini and H. helbingi could be two morphotypes within H. gaimersheimensis and H. gaimersheimensis Freudenberg, 1941 would be a junior synonyme of H. stehlini Shaub, 1925 . However, the species H. stehlini is based on an isolated lower jaw from an undetermined locality from Quercy (“Bach”, Old collections).

Morphological and dimensional variations of the material of Saint Privat-des-Vieux fall within those of H. gaimersheimensis , and are not completely similar with the type of H. stehlini . Ŋe teeth from Saint- Privat-des-Vieux are thus reported to H. gaimersheimensis ; because it is the only one species whose variability is known until now. It is the same for a few teeth from Sarèle (Vianey-Liaud 1972) and BoujacA.

Figures

FIG. 12. — Heterocricetodon gaimersheimensis Freudenberg,1941, from Saint-Privat-des-Vieux (Gard;Lower Chattian,MP 26): A, right M1 (reversed), SPV170: A1, occlusal view, A2, lingual view; B, left M2, SPV171: B1, occlusal view, B2, lingual view; C, right M3 (re- versed), SPV174: C1, occlusal view, C2, lingual view; D, right m1 (reversed), SPV175: D1, occlusal view, D2, lingual view; E, left m2, SPV178, occlusal view; F, left m3, SPV179: F1, occlusal view, F2, lingual view. Scale bar: 1 mm.