Pontophoca jutlandica Koretsky, Rahmat et Peters, 2014

Koretsky, I., Rahmat, S. & Peters, N., 2014, Rare Late Miocene Seal Taxa (Carnivora, Phocidae) From The North Sea Basin, Vestnik Zoologii 48 (5), pp. 419-432 : 421-423

Pontophoca jutlandica Koretsky, Rahmat et Peters , sp. n. (pl. 1, 2A, 2B; table 1)

H o l o t y p e. Incomplete right femur MSM 1788 , MidtsØnderjyllands Museum, Gram Slot, Denmark.

T y p e l o c a l i t y. Gram, Jutland, Denmark, claypit of Gram Teglvaerk (55.29°17' N, 9.05°2' E); Gram Formation, late Miocene (early-middle Tortonian, 8.0–11.5 ma).

E t y m o l o g y. After Jutland, the English name for Jylland (Danish: noun, neuter), Latinized to jutlandica (adj.) = from Jutland, the type area of the new species.

D i a g n o s i s. Femoral trochanteric fossa deep (in contrast to P. sarmatica ), reaching half of greater trochanter’s thickness; maximal distance across epicondyles 71.0 % of absolute length; condyles very different in size; plantar fossa very distinctive and deep, outlined by thin lateral border of lateral epicondyle.

D i s c u s s i o n. A monachine of small size,similar to P.sarmatica ( Koretsky, Grigorescu, 2002) . Differences from P. sarmatica (pl. 1, 1A, 1B): The distal end of the greater trochanter is narrower and has a V-shaped termination. The trochanteric fossa is deep, elongated along the femoral axis, wide, and reaches the middle of the greater trochanter’s length. This fossa is open on the proximal side of the greater trochanter. The condyles are very widely spaced (maximal distance across them is 71.1 % of the bone’s length). In contrast to P. sarmatica , the condyles are very different in size. The plantar fossa is located medial to the lateral epicondyle, making the outside border of the lateral epicondyle very thin.

The anatomical features and size of this femur are compatible with the similar bone of the type species of Pontophoca (table 1). We assign the femur to a new species, as it comes from the same geological time as the confidently referred material of Pontophoca sarmatica . The comparison with material of P. sarmatica is limited since the femur of P. jutlandica lacks the medial part of the bone. However, the preserved section of the femur bears enough distinct characters to distinguish it as a new species of Pontophoca . For detailed study and descriptions of humerus, femur, and other postcranial elements of Pontophoca sarmatica see Koretsky and Grigorescu (2002).

Figures

Fig. 3. Gryphoca nordica sp. n., paratype, proximal part of right humerus (reversed); Gram, Jutland, Denmark. Clay pit of Gram Teglvaerk, Gram Formation (late Miocene, early-middle Tortonian, 8.0–11.5 ma); MSM 1404x1 (cast in Geological Museum, Copenhagen, Denmark): 3A — caudal; 3B — cranial; 3C — medial; 3D — lateral view. Abbreviations: ac — anconeal crest; rf — radial fossa; sg — spiral groove.