Samokeros minotaurus Solounias, 1981
publication ID |
https://doi.org/ 10.5252/g2011n4a6 |
persistent identifier |
https://treatment.plazi.org/id/03EE374D-576B-C976-FD5F-FA2EFEE8FCE0 |
treatment provided by |
Marcus |
scientific name |
Samokeros minotaurus Solounias, 1981 |
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Samokeros minotaurus Solounias, 1981 ( Fig. 29 View FIG )
Samokeros minotaurus Solounias, 1981: 127 , text-figs 39, 40 partim.
Palaeoryx pallasi – Mecquenem 1925: pl. 4, fig. 1.
Tragocerus amaltheus – Mecquenem 1925: pl. 5, fig. 1.
Kostopoulos D. S. & Bernor R. L.
TYPE LOCALITY. — Samos, Greece (late Miocene).
MATERIAL EXAMINED. — Part of cranium with broken horn-cores, MAR1396 ( Mecquenem 1925: pl. IV, fig. 1 as P. pallasi ); palate, MAR3209 ( Mecquenem 1925: pl.V, fig. 1 as Tragocerus amaltheus ); P2-M3part, MAR3210 (labelled as T. amalthea ); part of right mandibular ramus with p2-m3, MAR3229 (labelled as P. pallasi ); part of right mandibular ramus with p4-m2, MAR3233 (labelled as P. pallasi ?); part of left mandibular ramus with p4-m3, MAR3230 (labelled as P. pallasi ?); part of left mandibular ramus with p2- p4, MAR2979.
DESCRIPTION AND REMARKS
Solounias (1981: 127) erroneously referred the frontlet MAR1323 ( Mecquenem 1925: pl. VII, fig. 1) to his new genus and species Samokeros minotaurus ; as it has been already shown this specimen belongs to the small heteronymous spiral horned antelope Nisidorcas . Solounias (1981) also provisionally ascribed to S. minotaurus the Maragheh frontlet AMNH27817, as well as, the cranium MAR1396 originally referred by Mecquenem (1925) to Palaeoryx pallasi and discussed later by Bohlin (1936) and Gentry (1971) who thought it represents a large Tragoportax .
The overall cranial structure of MAR1396 ( Fig. 29A, B View FIG ) is indeed very similar to that of Tragoportax but wider at the orbital level and with wider and low, box-like braincase that is more strongly bent on the face. It also differs in the supraorbital foramina placed into shallow depressions, the presence of a narrow triangular ethmoidal fissure defined by the nasals, frontals and lacrimals (but probably not by the maxillae), the inverse “U”-shaped fronto-nasal suture, the large and rather bilobed facial part of the jugal, the long and shallow lacrimal fossa with an additional small and round internal depression above the M2, the posterior position of the rather large infraorbital foramina (above P3), the more anteriorly opening choanae and the posterior position of posterior palatine foramina at the level of M3, the non elevated frontals, the much less developed rugose area restricted on the frontals and not limited posteriorly by the characteristic Tragoportax transverse bar, the presence of shallow frontal depressions behind the horn-cores, the elliptical basal cross-section of the horn-cores and the absence of keels on their preserved proximal part at least. Basic measurements of the cranium MAR1396 are (in mm): Wshc = 136.5, Wso = 51.9, Wbc = 98.6, Lfp-ocp = 85.0, Lfn-ocp = 190.3, DThcb = 44.0, APDhcb = 63.0.
Dental morphology and dimensions of the MNHN.F sample also suggest important differences from other late Miocene boselaphines ( Tables 20, 21). Thus, the premolar row is significantly shorter (58-60% of the upper and c. 66% of the lower molars instead of c. 74% and 68-72% respectively in Maragheh Tragoportax ), the P2 is short, squareshaped and bilobed lingually ( Fig. 29G, H View FIG ), the basal pillars are less common on the upper molars that bear central islets instead ( Fig. 29G, H View FIG ), the cement is rather abudant on the lower molars, the protoconid of p4 is pinched and both the p3 and the p4 are of primitive structure with widely open anterior valley and weak paraconid ( Fig. 29 View FIG D- F). The described dental material is of the size of Palaeoryx from the same locality, from which it differs in the much wider palate in front of P2, the much shorter P2, the narrower upper molars, the less developed paraconid of the p3 and p4, the thinner and longer metaconid of p3 and the weaker metastylid of the lower molars.
Kostopoulos D. S. & Bernor R. L.
The general morphological characters of the cranium MAR1396 exhibit important differences with both Tragoportax and Miotragocerus from Maragheh and other Eurasian sites and indicate a taxon with more advanced characters. The opisthocranial morphology of MAR1396 and the basal shape of the horn-cores are fully compatible with those of PIM99, holotype of Samokeros minotaurus . Additionally, PIM99 bears robust horn-cores similar to those of the frontlet AMNH27817 from Maragheh. The cranium and dental morphology, of MAR1396 closely compare with those of the skull AMNH 23036 from Samos ( Fig. 29C View FIG ), which is referred to Samokeros minotaurus ( Kostopoulos 2009a: 373) . The p3 and p4 morphology of the latter specimen is also identical to that from Maragheh (MAR2979, 3229, 3230, 3233).
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