Prosantorhinus germanicus ( WANG , 1929)

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

Prosantorhinus germanicus ( WANG, 1929)

N o t e. For earlier synonyms see Heissig (1972a: 65).

1929 v Dicerorhinus germanicus n. spec. – Wang, p. 191 ff., pl. 8, figs 1–4, pl. 9, figs 1, 2, text-fig. 2 B.

1929 v Diceratherium steinheimense (Jaeger) – Wang, p. 203, pl. 8, figs 5–7.

1929a v non Dicerorhinus germanicus nov. spec. – Wang, p. 4, pl. 2, fig. 5.

1934 Ceratorhinus tagicus ROMAN, partim – Roman and Viret, p. 35, pl. 9, figs 9, 11.

1965 Brachypotherium aurelianense Nouel – Ballesio et al., p. 75, pl. 7, fig. 3a, b.

1970 v Dicerorhinus sansaniensis-germanicus Gruppe part. – Mottl, pp. 83, 89, 98, 102.

1972a v Brachypodella n. gen. germanica – Heissig, p. 65 ff.

1974 v Prosantorhinus nov. nom. germanicus – Heissig,

p. 37. 1993 Prosantorhinus germanicus – Cerdeño, p. 65. 1996 Prosantorhinus germanicus – Cerdeño, p. 111 ff.,

pl. 18, figs 3–9, 11. 1996 v non Prosantorhinus germanicus – Cerdeño, p. 113 f.,

(Kutaenhausen, Langenau 1).

H o l o t y p e. Left maxilla fragment P2 – M3, BSPG

A.S.7.

T y p e l o c a l i t y. Georgensgmünd, Southern Germany.

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. Middle Miocene (MN 5 – MN 7),

Southern Germany, France.

D i a g n o s i s. Type species of the genus Prosantorhinus with a strong nearly terminal bulbous horn base and fused nasals. The finger like prolongation of the nasals in front of the horn base is feeble and directed ventrally. Postcranials robust, relatively small compared with tooth size. Manus tetradactyl.

D e s c r i p t i o n. After Cerdeño’s (1996) revision, no doubt remained about the taxonomy of this species. The odontology is documented in Peter (2002).

There are several distorted or fragmentary skulls from Sandelzhausen. The general shape is broad and short with flaring zygomatic arches. The temporal lines form a low, short sagittal crest. The occipital crista is broad and the occiput broadens ventrally towards the mastoid processes without any lateral constriction. The nasofrontal surface is deeply concave in profile and faintly convex transversally. The most peculiar structure is that of the horn base. It forms a nearly terminal bulbous, rough protuberance of the nasals, which is hollowed internally due to a pneumatic sinus. In front of this horn base is the very short tip of the nasals and is directed ventrally. The nasal bones arise rostrally and are fused at the tips in adults. They are short, triangular and broad at the base. The nasal incision is of medium depth and very high in front.

The mandibles show a less acute angle between the two halves than in most other rhinoceroses. The lower margin is curved and the branches are comparatively low. The symphysis is massive and slightly upturned with a short diastema. There is no space for the i1 between the large i2 on the narrow rostral side of the symphysis. The large diverging lower incisors show somewhat twisted crowns, which are strongly curved.

The limb bones are generally shortened and smaller than in other species. Its length ratio corresponds to the graviportal type. Carpal and tarsal bones are broad and low, metacarpals and metatarsals robust. Most of their characters are due to their proportions and are similar to the other known species. The fifth metacarpal is fully developed and bears a complete digit. Size and proportions can be seen best in the comparative diagrams in the appendix.