Leonhardtina godinoti, Solé & Falconnet & Yves, 2014
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publication ID |
https://doi.org/ 10.1111/zoj.12155 |
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persistent identifier |
https://treatment.plazi.org/id/03B0878A-D16C-A625-FCB4-FBB5C497FB40 |
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treatment provided by |
Marcus |
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scientific name |
Leonhardtina godinoti |
| status |
sp. nov. |
LEONHARDTINA GODINOTI SP. NOV. ( FIG. 6 View Figure 6 )
Diagnosis
Leonhardtina godinoti differs from Leonhardtina gracilis in its smaller size (15–20% smaller) and a taller P 3, less mesially projected paraconid, and longer talonid on M 3.
Chresonymy
1971: Prototomus cf. Protoproviverra palaeonictides in Rich, pp. 11–15.
Etymology
Dedicated to Prof. Marc Godinot, who has greatly contributed to the knowledge of Early Eocene European mammals.
Holotype
MNHN.F.L-195-Gr, right mandible with P 3, talonid of M 1, and M 2 −M 3, and alveoli of C, P 1 −P 2, and roots of P 4.
Type locality
MP10, Grauves ( France).
Measurements
See Table 4.
Description
MNHN.F.L-195-Gr is a right mandible, which bears P 3, M 2, and M 3. The mandible is very shallow. Its ventral margin is bowed ventrally. The symphysis extends below the mesial root of P 2. Two mental foramina are present, one between P 1 and P 2, the other below P 3. The masseteric fossa and angular process are rather low. The mental canal is visible ventrally on the anterior part of the specimen; it is more dorsally located on the distal part. The coronoid crest is broken; however, its mesial part indicates that the structure was probably close to the vertical, as seen in L. gracilis . The premolars are close to each other; there is only a tiny diastema between the P 2 and P 3.
All premolars are two-rooted. The P 2 is larger than the P 1 and was probably high, as in L. gracilis . The P 3 ends with a pointed apex. At its base, there is a tiny but distinct paraconid. A short talonid with two cusps (hypoconulid and entoconid) is also present. The P 3 is longer than the P 4.
The M 1 is broken on MNHN.F.L-195-Gr but the M 1 and M 2 appear morphologically similar even though the former is smaller than the latter. The morphology of M 2 is characterized by a sharply pointed and mesiodistally compressed trigonid. The metaconid is located slightly mesially relative to the protoconid. The paraconid is slightly smaller than the metaconid. The paracristid is long but is aligned transversally. The trigonid is a bit longer and wider than the talonid. The postfossid is very wide and deep. It is surrounded by three individualized cusps, of which the hypoconid is the highest. The hypoconulid is slightly projected distally. The cristid obliqua is oblique (labially shifted *Estimated on the basis of the roots.
†Weight estimated after Morlo (1999).
N, number of specimens; OR, observed range.
distally). The talonid of the M 3 is more elongated mesiodistally than on previous molars. The hypoconulid is projected distally. The entoconid is individualized. The postfossid is not narrow. The precingulid is distinct.
Discussion
The holotype of Leonhardtina godinoti, MNHN.F. L- 195-Gr, was previously referred by Rich (1971) to Prototomus cf. palaeonictides , but the re-evaluation of the latter species shows that it actually belongs to the genus Protoproviverra – which is close to Cynohyaenodon and Eurotherium (see above). Leonhardtina godinoti displays several plesiomorphic features amongst the Hyaenodontida, such as a shallow mandible, a distinct entoconid on the molars, a weak mesial projection of the paraconid, and a slightly reduced metaconid. Nevertheless, the holotype also displays apomorphic features, amongst which are closely placed premolars, a symmetric P 3 in lateral view, a developed paraconid on P 3, an entoconid on P 3, a P 3 longer than P 4, and a wide talonid on the lower molars. Some of these features (e.g. P 3 paraconid developed, wide talonid on molars) are shared with the small Middle Eocene proviverrines Cynohyaenodon , Lesmesodon , Proviverra , Allopterodon , and Leonhardtina . MNHN.F.L-195-Gr differs from Cynohyaenodon in its mesiodistally compressed and sharply pointed trigonid on M 2. This latter morphology is found in the other small Middle Eocene proviverrines. Moreover, MNHN.F.L-195-Gr displays a P 3 that is longer than P 4, as also observed in Leonhardtina , Proviverra , and Allopterodon . In contrast, it differs from the latter two genera and from Lesmesodon in having less developed cingulids on the premolars and molars and a narrower talonid on P 3. The morphology of MNHN.F.L-195-Gr therefore lacks the apomorphic characters of Proviverra and Allopterodon . The M 1 of MNHN.F.L-195-Gr is larger than those of Proviverra typica and Allopterodon torvidus , close in size to those of Lesmesodon edingeri and Allopterodon bulbosus , and smaller than those of Lesmesodon behnkeae and Allopterodon minor . Finally, the morphology of the fossils from Grauves is very similar to that of Leonhardtina gracilis from Geiseltal (MP12−13). They share the presence of a closed prefossid on molars and the lack of cingulids on premolars and molars. A P 3 that is longer than the P 4 is also notable.
The premolars and molars of MNHN.F.L-195-Gr are smaller than those of Leo. gracilis (15–20% smaller); MNHN.F.L-195-Gr is distinguished by a P 3 that is taller than long, a less mesially projected paraconid, and a longer talonid on M 3. All these features are plesiomorphic amongst Proviverrinae . The fossil from Grauves appears similar to that of the Middle Eocene Leo. gracilis , but represents a distinct species that lacks some of the apomorphic features of the latter. We propose naming this new species Leonhardtina godinoti sp. nov.
This discovery provides evidence for the presence of the genus Leonhardtina in MP10 of the Paris Basin, which significantly increases its stratigraphical range. This genus was previously restricted to the Middle Eocene of Geiseltal (MP12−13). Our study thus allows us to root this genus in the Early Eocene of Europe.
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