Prosantorhinus douvillei ( OSBORN , 1900)

Heissig, Kurt, 2017, Revision Of The European Species Of Prosantorhinus Heissig, 1974 (Mammalia, Perissodactyla, Rhinocerotidae), Fossil Imprint 73 (3 - 4), pp. 236-274 : 239-240

Prosantorhinus douvillei ( OSBORN, 1900)

N o t e. Alot of smaller collections cited from different localities have been omitted in the synonymy list because the limited amount of material does not allow a clear determination on the basis of the figures and the suggested classification is not different from any other.

1900 v Diceratherium douvillei , sp. nov. – Osborn, p. 239, fig. 6.

1907 Rh. ( Diceratherium ) Douvillei Osborn – Stehlin, pp. 527, 530 f.

1907 Rhinoceros sp. III – Stehlin, pp. 527, 531.

1908 v Diceratherium Douvillei Osborn – Mayet, p. 90 ff., fig. 25–27.

1908 v non Diceratherium Douvillei Osborn – Mayet, fig. 28.

1918 Ceratorhinus sansaniensis mut. Harlei nob. – Repelin, p. 68.

1925 Br. aurelianense – Stehlin and Helbing, p. 113, footnote.

1925 “ Rhinoceros turonensis Bourgeois” – Stehlin and Helbing, p. 114.

1934 Rhinoceros sp. – Roman and Viret, p. 65.

1948 Ceratorhinus sansaniensis mut. Harlei – Richard, p. 237.

1972a Brachypodella douvillei – Heissig, p. 70.

1979 Prosantorhinus douvillei – Ginsburg and Antunes, p. 493 f.

1979 Gaindatherium – Ginsburg and Antunes, p. 493 f.

1983 Gaindatherium (Iberotherium) rexmanueli – Antunes and Ginsburg, p. 30 ff., text-figs 12–20, pl. 6, figs 1–8, 10–12, pl. 7, figs 1–4.

1983 non Gaindatherium (Iberotherium) rexmanueli – Antunes and Ginsburg, pl. 6, fig. 9, pl. 7, fig. 5.

1987 Gaindatherium (Iberotherium) rexmanueli – Ginsburg et al., p. 306.

1996 Prosantorhinus douvillei ( Osborn, 1900) – Cerdeño, p. 112 ff.

1997 v Prosantorhinus germanicus – Antoine, pp. 400, 412.

1997 v Prosantorhinus germanicus – Antoine and Duranthon, pp. 202, 211.

1998 v Prosantorhinus cf. douvillei – Wermelinger, pp. 1–246, figs 5–8, pls 1–40.

2002 Prosantorhinus douvillei ( Osborn, 1900) – Antoine, p. 37.

H o l o t y p e. Left maxilla fragment with P2 – M2,

MNHN, Tav82 ( Osborn 1900: 239, fig. 6).

T y p e l o c a l i t y. Beaugency-Tavers, France.

S t r a t u m t y p i c u m. Middle Miocene (MN 5).

O c c u r r e n c e. Early to Middle Miocene (MN 3b –

MN 5), France, Southern Germany.

D i a g n o s i s. Medium sized species of the genus Prosantorhinus with subterminal, slightly swollen horn base and partly fused nasals with a rough finger like rostrally directed prolongation of the nasals in front of the horn base. Postcranials robust, relatively large compared with tooth size. Manus variably tetra- or tridactyl.

D e s c r i p t i o n. The most comprehensive material is from Montréal-du-Gers (MN 4b), also known as Béon, the best almost undistorted skull is from Langenau near Ulm (MN 4b). On the basis of this specimen and the more or less distorted skulls from Montréal-du-Gers, the dental and skull characters can be described as follows. The general shape is broad and short with flaring zygomatic arches. The occiput is generally broad but the temporal lines unite to form a sagittal crest at least in males. The widest part of the occiput lies at the mastoid processes. The nasofrontal surface is concave in profile and convex transversally, more convex at the nasal base than over the frontals. The horn base is very similar in all primitive Teleoceratini , but more robust than in Diaceratherium . It forms a slightly swollen, rough thickening of the nasals, which is subterminal. In front of this structure each nasal bone terminates in a narrow, finger like, rough process. The nasal bones arise frontally and are fused below the horn base in old animals. They are rather short, narrowing rostrally from the broad frontals and tapering at the end. The nasal incision is of medium depth and widely open rostrally.

The angle between the two halves of the mandibles is wide, similar as in Prosantorhinus germanicus . The lower margin of the corpus is curved and the branches are comparatively low. The symphysis is massive, broad and slightly upturned with a short diastema. The large incisors are close to one another. There is no twist on the incisor crowns which are less strongly curved than in the type species.

The limb bones are robust and large compared to the tooth size. Their length ratio corresponds to the graviportal type. Carpal and tarsal bones are broad and short, metacarpals and metatarsals less robust than in the type species. In the Montréal-du-Gers (Béon) collection the fifth metacarpal is generally reduced to a knob, but there is one specimen of a less reduced MC V with an articular facet for the ground phalanx. Unfortunately the most lateral metacarpal is not known from earlier horizons. Size and proportions can be seen best in the comparative diagrams .

There seems to be a problem with the remains from Portugal which have been named as Gaindatherium (Iberotherium) rexmanueli ( Antunes and Ginsburg 1983: 30) . The measurements of the upper molars would better fit the species P. aurelianensis, but the morphology, especially of the last molars, is identical with P. douvillei . Possibly the rather large size of these teeth, according to the literature, is due to different measuring methods.