''Cullinia'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

litoptern Litopterna (from grc, λῑτή πτέρνα "smooth heel") is an extinct order of fossil hoofed mammals from the Cenozoic era. The order is one of the five great orders of South American ungulates that were endemic to the continent, until the ...

, an order of

South American native ungulates South American native ungulates, commonly abbreviated as SANUs, are extinct ungulate-like mammals of controversial affinities that were indigenous to South America prior to the Great American Biotic Interchange. They comprise five major groups ...

that included

horse The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million ...

-like and

camel A camel (from: la, camelus and grc-gre, κάμηλος (''kamēlos'') from Hebrew or Phoenician: גָמָל ''gāmāl''.) is an even-toed ungulate in the genus ''Camelus'' that bears distinctive fatty deposits known as "humps" on its back. ...

-like animals such as ''

Macrauchenia ''Macrauchenia'' ("long llama", based on the now-invalid llama genus, ''Auchenia'', from Greek "big neck") was a large, long-necked and long-limbed, three-toed native South American mammal in the order Litopterna. The genus gives its name to its ...

''. It is only known from fragmentary remains. ''Cullinia levis'' is known from

Chasicoan The Chasicoan ( es, Chasiquense or es, Chasicoense) age is a period of geologic time from 10–9 Ma within the Late Miocene epoch of the Neogene, used more specifically within the SALMA classification in South America. It follows the Mayoan and ...

remains found in the

Arroyo Chasicó Formation Arroyo often refers to: * Arroyo (creek), an intermittently dry creek Arroyo may also refer to: People * Arroyo (surname) Places United States ;California * Arroyo Burro Beach, a public beach park in Santa Barbara County, California * Arroyo ...

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, t ...

, and remains from the Brazilian state of

Acre The acre is a unit of land area used in the imperial and US customary systems. It is traditionally defined as the area of one chain by one furlong (66 by 660 feet), which is exactly equal to 10 square chains, of a square mile, 4,840 square ...

and the

Huayquerian The Huayquerian ( es, Huayqueriense) age is a period of geologic time (9.0–6.8 Ma) within the Late Miocene epoch of the Neogene, used more specifically within the SALMA classification. It follows the Mayoan and precedes the Montehermosan age ...

Ituzaingó Formation The Ituzaingó Formation ( es, Formación Ituzaingó), in older literature also described as Entre Ríos or Entrerriana Formation, is an extensive geological formation of Late Miocene (Tortonian, or Huayquerian in the SALMA classification) age in ...

have been assigned to ''Cullinia'' sp. .

History and naming

''Cullinia'' was described in 1931 by Cabrera and Kraglievich, from MLP 29-IX-178, an holotype containing several fragmentary remains including a mandible and a metatarsal. In 1995, Bond and López add to the holotype other remains from the upper dentition. It was named from the

Araucanian The Mapuche ( (Mapuche & Spanish: )) are a group of indigenous inhabitants of south-central Chile and southwestern Argentina, including parts of Patagonia. The collective term refers to a wide-ranging ethnicity composed of various groups who sh ...

word "cullin", meaning "animal".

Description

''Cullinia'' was a slender, small

Macraucheniidae Macraucheniidae is a family in the extinct South American ungulate order Litopterna, that resembled various camelids. The reduced nasal bones of their skulls was originally suggested to have housed a small proboscis, similar to that of the sa ...

. It had proportionally larger metapodials than '' Theosodon'', and its first lower molar was absent.

Classification

Below is a phylogenetic tree of the

, based on the work of McGrath ''et al''. 2018, showing the position of ''Cullinia''.

Palaeoecology

The Arroyo Chasicó formation was, in the Miocene, on the tip of a peninsula bordered by the Paranaense Sea. ''Cullinia'' would have lived alongside various genera of

Cingulata Cingulata, part of the superorder Xenarthra, is an order of armored New World placental mammals. Dasypodids and chlamyphorids, the armadillos, are the only surviving families in the order. Two groups of cingulates much larger than extant arma ...

, including the last horned armadillo '' Epipeltephilus'', the dasypodids '' Chasicotatus'', the chlamyphorid '' Vetelia'', the euphractine ''

Proeuphractus ''Proeuphractus'' is an extinct genus of xenarthran, related to the modern armadillos. It lived from the Early to the Late Miocene, and its fossilized remains were discovered in South America. Description This animal was quite similar to the mo ...

'', the pampathere '' Kraglievichia'', and the

glyptodont Glyptodonts are an extinct subfamily of large, heavily armoured armadillos. They arose in South America around 48 million years ago and spread to southern North America after the continents became connected several million years ago. The best-k ...

Kelenkura ''Kelenkura'' is an extinct genus of heavily armored mammals belonging to the subfamily Glyptodontinae, from the family Chlamyphoridae that contain most of the modern armadillos. It was a medium-sized South American animal, distantly related to ' ...

''. Other

xenarthra Xenarthra (; from Ancient Greek ξένος, xénos, "foreign, alien" + ἄρθρον, árthron, "joint") is a major clade of placental mammals native to the Americas. There are 31 living species: the anteaters, tree sloths, and armadillos. Ex ...

ns includes several genera of

ground sloths Ground sloths are a diverse group of extinct sloths in the mammalian superorder Xenarthra. The term is used to refer to all extinct sloths because of the large size of the earliest forms discovered, compared to existing tree sloths. The Cari ...

, such as the

mylodontid Mylodontidae is a family of extinct South American and North American ground sloths within the suborder Folivora of order Pilosa, living from around 23 million years ago (Mya) to 11,000 years ago. This family is most closely related to another f ...

'' Octomylodon'', the megalonychid '' Protomegalonyx'', the nothrotheriids '' Xyophorus'' and '' Chasicobradys'', and the megatheriid '' Anisodontherium''. Several genera of

rodents Rodents (from Latin , 'to gnaw') are mammals of the order Rodentia (), which are characterized by a single pair of continuously growing incisors in each of the upper and lower jaws. About 40% of all mammal species are rodents. They are na ...

were recovered from the formation, such as the earliest genera of

tuco-tucos A tuco-tuco is a neotropical rodent in the family Ctenomyidae.Parada, A., G. D’Elia, C.J. Bidau, and E.P. Lessa. 2011. Species Groups and the Evolutionary Diversification of Tuco-Tucos, genus ''Ctenomys'' (Rodentia: Ctenomyidae). ''Journal of M ...

, maras and cavioids such as '' Cardiomys'', '' Procardiomys'' and '' Cardiatherium'', octodontids such as '' Chasicomys'' and '' Chasichimys'', the echimyids '' Pattersomys'', the plain viscacha ''Lagostomus telenkechanum'' and its relative '' Prolagostomus'', and the large-sized dinomyid '' Carlesia''.

Meridiungulates South American native ungulates, commonly abbreviated as SANUs, are extinct ungulate-like mammals of controversial affinities that were indigenous to South America prior to the Great American Biotic Interchange. They comprise five major groups ...

were also present in the formation, with the fellow

genera such as the fellow macraucheniid '' Paranauchenia'', and the proterotheriid ''

Neobrachytherium ''Neobrachytherium'' is an extinct genus of proterotheriid mammal from the Late Miocene of Argentina and Uruguay. It is represented by multiple species, including the type ''N. intermedium'', originally named in 1891 by Moreno and Mercerat as a ...

'', while notoungulates were represented by genera such as the large-sized late surviving homalodotheriid '' Chasicotherium'', the

toxodontid Toxodontidae is an extinct family of notoungulate mammals, known from the Oligocene to the Holocene (11,000 BP) of South America, with one genus, '' Mixotoxodon'', also known from the Pleistocene of Central America and southwestern North Ame ...

Paratrigodon ''Paratrigodon'' is an extinct genus notoungulate belonging to the subfamily Toxodontinae, containing one species, ''P. euguii''. Like its close relative ''Trigodon'', it is known for the presence of a horn-like protuberance on its forehead. Fos ...

'', the

interatheriid Interatheriidae is an extinct family of notoungulate mammals from South America. Interatheriids are known from the Middle Eocene ( Mustersan) to the Early Pliocene ( Montehermosan).McKenna & Bell, 1997Linares, 2004 These animals were princip ...

'' Protypotherium'', the mesotheriid '' Typotheriopsis'', and the hegetotheriids '' Paedotherium'', '' Pseudohegetotherium'' and '' Hemihegetotherium''. The largest

predators Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

were the

sparassodonts Sparassodonta (from Greek to tear, rend; and , gen. , ' tooth) is an extinct order of carnivorous metatherian mammals native to South America, related to modern marsupials. They were once considered to be true marsupials, but are now thou ...

'' Pseudolycopsis cabrerai'' and '' Lycopsis viverensis'', and the small

terror bird Phorusrhacids, colloquially known as terror birds, are an extinct clade of large carnivorous flightless birds that were one of the largest species of apex predators in South America during the Cenozoic era; their conventionally accepted tempo ...

Psilopterus ''Psilopterus'' (Greek for "bare wing") is an extinct genus of phorusrhacid ("terror bird") from the Middle Oligocene to possibly the Late Pleistocene of Argentina and Uruguay. Compared to other phorusrhacids, members of the genus are both relat ...

''.

References

{{Taxonbar, from=Q110639950 Macraucheniids Miocene mammals of South America Chasicoan Huayquerian Neogene Argentina Fossils of Argentina Neogene Brazil Fossils of Brazil Ituzaingó Formation Fossil taxa described in 1931 Prehistoric placental genera