Palaeo Vertebrata - Articles

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February 1972
Vol. 05, Fasc. 2
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Print ISSN: 0031-0247
Online ISSN: 2274-0333
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PalaeovertebrataVol. 05, Fasc. 2:45-78. 1972
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Etude du crâne de Pachynolophus lavocati n. sp. (Perissodactyla, Palaeotheriidae) des Phosphorites du Quercy
Jean-Albert Remy
Keywords: Perissodactyla; Quercy phosphorites

doi: 10.18563/pv.5.2.45-78
 

Cite this article: Remy J.-A., 1972. Etude du crâne de Pachynolophus lavocati n. sp. (Perissodactyla, Palaeotheriidae) des Phosphorites du Quercy. Palaeovertebrata 5 (2): 45-78. doi: 10.18563/pv.5.2.45-78

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Abstract

The genus Pachynolophus, one of the poorest known of the Palaeotheriidae, includes the brachyodont forms with reduced and non-molariform premolars and with upper molars lacking a mesostyle. Quantitative characters (divers surface indications and elongation of the teeth), while demonstrating a close relationship to Hyracotherium, permit a better differentiation of the genus, confirm its specific splitting, and permit the distinction of three lineages. The skull from Memerlein is taken as the type of a new species, P. Iavocati, of which the dentition is extremely characterized by its lophiodonty, the strong reduction of the premolars and the reduction of the cingula. This characterization testifies to a late age which extends the existence of the genus quite near to the Eocene-Oligocene limit. Compared with the only two skulls known of related species (Hyracotheríum vulpiceps and Pachynolophus Iivinierensis), that from Memerlein is distinguished by progressive characters affecting diferent regions but most particularly the braincase; it is not possible, however, to isolate within this evolution the part which leads to a systematic differentiation. Modernization is translated by a considerable increase in size of the braincase, principally in the frontal region, a development of the facial region with anterior displacement of the dental series and a greater specialization of the masticatory apparatus. This evolution parallels the history of the Equidae of the North American early Tertiary, but certain particularities, the form of the alisphenoid, the presence of an anterior frontal foramen, and the structure of the paroccipital apophysis, testifies to the independance of the European forms. 



Published in Vol. 05, Fasc. 2 (1972)

Bibliography

BUTLER P. M., 1952. Molarization of the premolars in the Perissodactyla. Proc. Zool. Soc. London, 121 (4): 819-843, 93 fig.
 
COOPER C., 1932. The Genus Hyracotherium. A revision and description of new specimens found in England. Philos. Trans. Roy. Soc. London, B, 221: 431-448, 3 fig., 3 pl.
 
CRUSAFONT-PAIRO M. et REMY J. A., 1970. Les Equoidea (Perissodactyla) de l'Eocène préaxial pyrénéen espagnol. Bull. Mus. Nat. Hist, Nat., 42 (2) : 428-434,2 fig.
 
DEPERET C., 1901. Révision des formes européennes de la famille des Hyracothéridés. Bull. Soc. Géol. Fr., 4 (1): 199-225, 2 pl.
 
DEPÉRET C., 1917. Monographie de la Faune de mammifères fossiles du Ludien inférieur d'Euzet-Ies-Bains (Gard). Ann. Univ, Lyon, n. sér., 1 Sc. Med., 40: 1-228, 25 pl.
 
EARLE C., 1896. Notes on the Fossil Mammalia of Europe. I, Comparison of the American and European forms of Hyracotherium. Amer. Natur., 30: 131135.
 
EDINGER T., 1929. Die fossilen Gehirne. Zeits. jür gesam. Anat., 3 (28): 1-249.
 
EDINGER T., 1948. Evolution of the horse brame. Mem. Geol. Soc. Amer., 25: 1-174, 24 fig., 4 pl.
 
EDINGER T., 1950. Frontal sinus evolution (particularly in the Equidae). Bull. Mus. Comp. Zool., 103 (8): 411-496, 7 fig., 9 pl.
 
EDINGER T. and KITTS D. B., 1954. The foramen ovale. Evolution, 8: 389-404, 4 fig.
 
GREGORY W. K., 1920. Studies in Comparative Myology and Osteology, n° V. On the Anatomy of the Preorbital Fossae of Equidae and other Ungulates. Bull. Am. Mus. Nat. Hist., 42 (3): 265-284, 26 fig., 1 pl.
 
HARTENBERGER J.-L., 1969. Les Pseudosciuridae (Mammalia, Rodentia) de l'Eocène moyen de Bouxwiller, Egerkingen et Lissieu. Palaeovertebrata 3 (2): 27-64. doi: 10.18563/pv.3.2.27-64
 
KITTS D. B., 1956. American Hyracotherium (Perissodactyla, Equidae). Bull. Amer. Mus. Nat. Hist., 110 (1) : 1-60, 10 fig., 7 pl.
 
LE GROS CLARK W. E., 1934. Early forerunners of Man. A morphological study of the evolutionary origin of the Primates: 1-296, 89 fig., Baillière, Tindall and Cox, London.
 
LOUIS P., 1966. Note sur un nouveau gisement situé à Condé-en-Brie (Aisne) et renfermant des restes de Mammifères de l'Eocène inférieur. Ann. Univ. et A.R.E.R.S. Reims, 4: 108-118.
 
MAC KENNA M. C., 1960. Fossil Mammalia from the early Wasatchian Four Mile fauna, Eocene of northwest Colorado. Univ, Calif. Publ. Geol. Sci., 37: 1-130, 64 fig.
 
MONTANE L. et BOURDELLE E., 1913. Anatomie régionale des animaux domestiques. 1 Cheval: I-VII, 1-1069, 564 fig., Baillière, Paris.
 
OSBORN H. F., 1918. Equidae of the Oligocene, Miocene and Pliocene of North America, Iconographie Type Revision. Mem. Am. Mus. Nat. Hist., n. ser., 2 (1) : 1-217, 173 fig., 54 pl.
 
POMEL A., 1847. Notes sur les mammifères et reptiles fossiles des terrains éocènes de Paris, inférieurs au dépôt gypseux. Arch. Sci. Phy. et Natur., Genève, 4:326-330.
 
REMY J. A., 1967. Les Palaeotheridae (Perissodactyla) de la faune de Mammifères de Fons 1 (Eocène supérieur). Palaeovertebrata 1 (1): 1-46. doi: 10.18563/pv.1.1.1-46
 
RUSSELL D. E., 1964. Les Mammifères paléocènes d'Europe. Mém. Mus. Nat. Hist. Nat. n. sér., C, 13: 1-324, 73 fig., 16 pl.
 
SAVAGE D. E., RUSSELL D. E. and LOUIS P., 1965. European Eocene Equidae (Perissodactyla). Univ. Calif. Publ. Geol. Sci., 56: 1-94, 1 pl.
 
SIMPSON G. G., 1945. The Principles of Classification and a Classification of Mammals. Bull. Am. Mus. Nat. Hist., 85: I-XVI, 1-350.
 
SIMPSON G. G., 1952. Notes on British Hyracotheres. Lin. Sac. Jour. Zool., 42 (284): 195-206, 4 fig., 2 pl.
 
STEHLIN H. G., 1905. Die Säugetiere des Schweizerischen Eocäens, Critischer Catalog der Materialen. 3ter teil. Abh. Schweiz: pal. Ges., 32 : 447-595, 34 fig., 2 pl.
 
STEHLIN H. G., 1909. Remarques sur les faunules de Mammifères des couches éocènes et oligocènes du Bassin de Paris. Bull. Soc. Géai. Fr., 4 (9) : 488-520.
 
STEHLIN H. G., 1938. Zur Charakteristik. einiger Palaeotherium-arten des Oberen Ludien. Schweiz, pal. Ges., 31 (2) : 263-292, 17 fig., 1 pl.
 
THALER L., 1966. Les Rongeurs fossiles du Bas-Languedoc dans leurs rapports avec l'histoire des faunes et la stratigraphie du Tertiaire d'Europe. Mém. Mus. Nat. Hist. Nat., n. sér., C, 17: 1-295, 25 fig.;: 27 pl.
  


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