| 词条 | Leontinia |
| 释义 |
| name = Leontinia | image = Leontinia.jpg | image_width = 250px | fossil_range = Late Oligocene (Deseadan) ~{{fossil range|28.4|23.03}} | regnum = Animalia | phylum = Chordata | classis = Mammalia | ordo = Notoungulata | subordo = Toxodonta | familia = Leontiniidae | genus = Leontinia | genus_authority = Ameghino 1895 | subdivision_ranks = Species | subdivision =
}}Leontinia is an extinct genus of leontiniid notoungulate. Fossils have been found in the Deseado and Sarmiento Formations in Argentina and São Paulo Formation of Brazil, and are the most abundant remains of any animal found there. The genus dates back to the Late Oligocene, Deseadan in the SALMA classification.[1] DescriptionIn Leontinia, the first incisors of the upper jaw are small cropping teeth, while the second are elongated and form caniniform tushes. In the lower jaw it is the third incisors have developed into tushes, not the second. Variations and incisor length have been used to distinguish different species from one another and may possibly provide evidence of sexual dimorphism among certain species. In fact, it has been suggested that different species assigned on the basis of tooth proportion may only represent different genders of the same species.[2] The nasal bones are highly elevated from the nasal cavity and suggest that the animal may have possessed horns resembling those of the rhinocerid Diceratherium. References{{Portal|Paleogene|Paleontology|Prehistoric mammals|Prehistory of South America}}1. ^Leontinia at Fossilworks.org {{Taxonbar|from=Q1129228}}{{paleo-mammal-stub}}2. ^Loomis, F. B. (1914). The Deseado formation of Patagonia. Rumford Press, Concord. pp. 109-121. 9 : Toxodonts|Oligocene mammals of South America|Deseadan|Paleogene Argentina|Paleogene Brazil|Fossils of Argentina|Fossils of Brazil|Fossil taxa described in 1895|Taxa named by Florentino Ameghino |
| 随便看 |
开放百科全书收录14589846条英语、德语、日语等多语种百科知识，基本涵盖了大多数领域的百科知识，是一部内容自由、开放的电子版国际百科全书。