''Maddenia'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

astrapothere Astrapotheria is an extinct order of South American and Antarctic hoofed mammals that existed from the late Paleocene to the Middle Miocene, ."The uruguaytheriine Astrapotheriidae from the rich middle Miocene Honda Group of the upper Magdale ...

, meridiungulate herbivore mammals characterised by its large tusks and the development of

proboscis A proboscis () is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate. In invertebrates, the term usually refers to tubular mouthparts used for feeding and sucking. In vertebrates, a proboscis is an elong ...

, endemic of

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere at the northern tip of the continent. It can also be described as the southe ...

. This genus was discovered in an outcrop near to the Lake Colhué Huapi in the place La Cantera, in the

Chubut Province Chubut ( es, Provincia del Chubut, ; cy, Talaith Chubut) is a province in southern Argentina, situated between the 42nd parallel south (the border with Río Negro Province), the 46th parallel south (bordering Santa Cruz Province), the Andes ra ...

, in

Argentina Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...

, in sediments corresponding to the

Sarmiento Formation The Sarmiento Formation (Spanish: ''Formación Sarmiento''), in older literature described as the Casamayor Formation, is a geological formation in Chubut Province, Argentina, in central Patagonia, which spans around 30 million years from the mid- ...

, that dates of the

Late Oligocene The Chattian is, in the geologic timescale, the younger of two ages or upper of two stages of the Oligocene Epoch/Series. It spans the time between . The Chattian is preceded by the Rupelian and is followed by the Aquitanian (the lowest stage ...

(

Deseadan The Deseadan ( es, Deseadense) age is a period of geologic time (29.0–21.0 Ma) within the Oligocene epoch of the Paleogene to the Early Miocene epoch of the Neogene, used more specifically within the SALMA classification of South America. It fo ...

South American land mammal age The South American land mammal ages (SALMA) establish a geologic timescale for prehistoric South American fauna beginning 64.5 Mya (unit), Ma during the Paleocene and continuing through to the Late Pleistocene (0.011 Ma). These periods are referre ...

).''Maddenia''
at

Fossilworks Fossilworks is a portal which provides query, download, and analysis tools to facilitate access to the Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals ...

.orgAlejandro G. Kramarz and Mariano Bond (2009) A new oligocene astrapothere (Mammalia, Meridiungulata) from Patagonia and a new appraisal of astrapothere phylogeny
''Journal of Systematic Palaeontology'', 7 : pp 117-128

Etymology

The name of the genus ''Maddenia'', is in homage to the palaeontologist Richard Madden, by his contributions to the palaeontology of South America, whereas the name of the type species and only known, ''Maddenia lapidaria'', derives of the

Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...

''lapidarius'', "of stone".

Description

This species is based in the

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

MPEF PV 7735, a fragment of

jawbone In anatomy, the mandible, lower jaw or jawbone is the largest, strongest and lowest bone in the human facial skeleton. It forms the lower jaw and holds the lower teeth in place. The mandible sits beneath the maxilla. It is the only movable bone ...

with molar and

premolar The premolars, also called premolar teeth, or bicuspids, are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant in the permanent set of teeth, making eight premolars total in the mouth ...

teeth associated and a partial canine associated, in addition to several additional specimens that include isolated teeth and other fragments of jaws. From these remains it was established that ''Maddenia'' was a small astrapothere, near of 50% smaller than ''

Astraponotus ''Astraponotus'' is an extinct genus of astrapotheriids. It lived during the Middle-Late Eocene (in the Mustersan and Tinguirirican of the South American land mammal ages (SALMA), 48-33.9 million years ago) and its fossil remains have been fou ...

''. Its molar were high, with complex crowns and with canines moderately developed, characteristics of the advanced astrapotheres of big size of the Oligocene and the Miocene (like ''

Astrapotherium ''Astrapotherium'' ("lightning beast") is an extinct genus of South American mammals that vaguely resembled a small elephant or large tapir. However, it was unrelated to elephants or tapirs, but was instead related to other extinct South American ...

'' and ''

Granastrapotherium ''Granastrapotherium'' is an extinct genus of ungulate mammals, described from remains found in rocks of the Honda Group in the Tatacoa Desert, in the Colombian departments of Huila and Tolima, at the Miocene fossil site La Venta. The only spe ...

''), which suggests that it must to occupy a habitat differentiated regarding other forms of big size, and that by its anatomical characteristics constitutes an intermediate form between the primitive forms like ''

Albertogaudrya ''Albertogaudrya'' is an extinct genus of astrapotherian mammal that lived in present-day Salta, Argentina (, paleocoordinates ) during the Eocene (Casamayoran SALMA The South American land mammal ages (SALMA) establish a geologic timescale f ...

'' and the astrapotherids like ''Parastrapotherium'', with which conform sister taxa to the two subfamilies of the family Astrapotheriidae,

Astrapotheriinae Astrapotheriidae is an extinct family of herbivorous South American land mammals that lived from the Late Eocene (Mustersan SALMA) to the Middle Miocene (Laventan SALMA) . The most derived of the astrapotherians, they were also the largest and mo ...

and Uruguaytheriinae.

Phylogeny

Cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ...

according to Bond ''et'' al., 2011, standing out the phylogenetic position of ''Maddenia'':

References

{{Taxonbar, from=Q5989280 Meridiungulata Oligocene mammals of South America Deseadan Paleogene Argentina Fossils of Argentina Fossil taxa described in 2009 Prehistoric placental genera Golfo San Jorge Basin Sarmiento Formation