''Colombitherium'' is an extinct mammal from

Late Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', "d ...

Colombia. It has originally been assigned to the order Pyrotheria and the family Colombitheriidae, although a later detailed analysis of the fossil questions that classification. A fossil jawbone of approximately length of ''Colombitherium'' has been found by

Texas Petroleum Texaco, Inc. ("The Texas Company") is an American oil brand owned and operated by Chevron Corporation. Its flagship product is its fuel "Texaco with Techron". It also owned the Havoline motor oil brand. Texaco was an independent company until i ...

in 1945, in the Upper Eocene strata of the middle Gualanday Group in the department of Tolima,

Central Ranges Central Ranges (code CER) is an Australian bioregion, with an area of 101,640.44 square kilometres (39,244 sq mi) spreading across two states and one territory: South Australia, Western Australia, and the Northern Territory.Andes The Andes, Andes Mountains or Andean Mountains (; ) are the longest continental mountain range in the world, forming a continuous highland along the western edge of South America. The range is long, wide (widest between 18°S – 20°S ...

Etymology

The genus ''Colombitherium'' means "Beast from Colombia". The species

epithet An epithet (, ), also byname, is a descriptive term (word or phrase) known for accompanying or occurring in place of a name and having entered common usage. It has various shades of meaning when applied to seemingly real or fictitious people, di ...

''tolimense'' refers to the department of Tolima, where the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen( ...

has been found.Billet et al., 2010, p.319Basic information about ''Colombitherium''
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Description

The genus is only known from a single jawbone with some teeth, found by

in 1945, a specimen approximately in length, recovered from the Late Eocene middle part of the Gualanday Group on the San Pedro

finca In English usage, a ''finca'' (; ) refers to a piece of rural or agricultural land, typically with a cottage, farmhouse or estate building present, and often adjacent to a woodland or plantation. Overview Especially in tourism, the term has re ...

, Alto San José,

Chaparral Chaparral ( ) is a shrubland plant community and geographical feature found primarily in the U.S. state of California, in southern Oregon, and in the northern portion of the Baja California Peninsula in Mexico. It is shaped by a Mediterrane ...

, Tolima. The teeth, molars and premolars of a kind known as bilophodont, which are present in the pyrotheres - were considered as evidence that this genus could be an ancestor of the advanced pyrotheres as '' Pyrotherium''.Hoffstetter, 1971, p.39 ''Colombitherium'' has first been described by Hoffstetter in 1970, with a revised interpretation published by Billet ''et al''. in 2010.Billet ''et al''., 2010, p.320 The detailed descriptions by Billet ''et al''. show the differences between ''Colombitherium'' and other pyrotherians: the features of the bilophodont teeth of Colombitherium are actually found in several groups of placental mammals, which implies that ''Colombitherium'' and another possibly related taxon, '' Proticia'' could not be part of Pyrotheria. The authors maintain "the referral of ''Colombitherium'' to Pyrotheria is therefore weakly supported, and it must be considered as highly hypothetical."Billet et al., 2010, p.323 In any case, the lack of further evidence means that ''Colombitherium'' and ''Proticia'' must be classified in a separate

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

, Colombitheriidae which is tentatively classified as a primitive clade in Pyrotheria. Also the absolute age of the strata where the fossil jawbone has been found is questioned. The age has been originally defined by De Porta in 1962 on the basis of the

pollen Pollen is a powdery substance produced by seed plants. It consists of pollen grains (highly reduced microgametophytes), which produce male gametes (sperm cells). Pollen grains have a hard coat made of sporopollenin that protects the gametop ...

'' Verrucatosporites usmensis'' and '' Cicatricosisporites sp.'' The last occurrence of '' Echitriporites trianguliformis orbicularis'' indicates a Late Eocene to

Early Oligocene The Rupelian is, in the geologic timescale, the older of two ages or the lower of two stages of the Oligocene Epoch/ Series. It spans the time between . It is preceded by the Priabonian Stage (part of the Eocene) and is followed by the Chattia ...

age for the upper layers of the Gualanday Group.Billet et al., 2010, p.324

References

Bibliography

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External links

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''Colombitherium tolimense''
- Paleontología en Colombia {{Taxonbar, from=Q5777680 Meridiungulata Eocene mammals of South America Paleogene Colombia Fossils of Colombia Fossil taxa described in 1970 Taxa named by Robert Hoffstetter Prehistoric placental genera

Etymology

Description

See also

References

Bibliography

External links