''Falcontoxodon'' is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of toxodontid notoungulate that lived from the late

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Pleistocene The Pleistocene ( ; referred to colloquially as the ''ice age, Ice Age'') is the geological epoch (geology), epoch that lasted from to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fin ...

in what is now

Venezuela Venezuela, officially the Bolivarian Republic of Venezuela, is a country on the northern coast of South America, consisting of a continental landmass and many Federal Dependencies of Venezuela, islands and islets in the Caribbean Sea. It com ...

Fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

s of this genus have been found in the

Chapadmalalan The Chapadmalalan age is a period of geologic time (4.0–3.0 Ma) within the Pliocene epoch of the Neogene used more specifically with South American Land Mammal Ages. It follows the Montehermosan and precedes the Uquian age. Fossil content ...

Uquian The Uquian age is a period of geologic time (3.0–1.5 Ma) within the Pliocene and Pleistocene epochs of the Neogene used more specifically with South American Land Mammal Ages. It follows the Montehermosan The Montehermosan age is a period of ...

Codore Formation, as well as in the more recent

Ensenadan The Ensenadan age is a period of geologic time (1.2–0.8 Ma) within the Early Pleistocene epoch of the Quaternary used more specifically with South American Land Mammal Ages. It follows the Uquian and precedes the Lujanian The Lujanian age is a ...

San Gregorio Formation.

Description

The genus ''Falcontoxodon'' was described in 2018 by Carrillo ''et al'' with AMU-CURS 765, an almost complete skull with a well-preserved dentition found in the Algodones Member of the Codore Formation. In the same article, two other specimens assigned to ''Falcontoxodon'' were described from the Vergel Member of the San Gregorio Formation, assigned respectively to ''Falcontoxodon'' aff. ''aguilerai'' and ''Falcontoxodon'' sp. In 2021, an analysis of the San Gregorio Formation by Carrillo-Briceño ''et al'' uncovered thirty-three additional remains, mostly teeth, that were assigned to the genus. The name of the genus, ''Falcontoxodon'', refers to its relative, ''

Toxodon ''Toxodon'' (meaning "bow tooth" in reference to the curvature of the teeth) is an extinct genus of large ungulate native to South America from the Pliocene to the end of the Late Pleistocene. ''Toxodon'' is a member of Notoungulata, an order of ...

'', and to the Venezuelan state of

Falcón Falcón State (, ) is one of the 23 States of Venezuela, states of Venezuela. The state capital is Coro, Venezuela, Coro. The state was named after Juan Crisóstomo Falcón. History Early history Present day Falcón State was first explored ...

in Northern Venezuela, where the holotype remains have been found. The species' name, ''aguillerai'', honours the Venezuelan

paleontologist Paleontology, also spelled as palaeontology or palæontology, is the scientific study of the life of the past, mainly but not exclusively through the study of fossils. Paleontologists use fossils as a means to classify organisms, measure geolo ...

Orangel Aguilera. ''Falcontoxodon'' was a medium-sized Toxodontinae, estimated to have weighted around 800 kg, roughly half the weight of ''

''. It had a pear-shaped, 55 cm long skull in frontal view, with an elongated nasal. The third upper incisor was absent and the canine was reduced. The lower molars were

hypsodont Hypsodont is a pattern of dentition characterized by with high crowns, providing extra material for wear and tear. Some examples of animals with hypsodont dentition are cows and horses; all animals that feed on gritty, fibrous material. The oppos ...

, and the second lower incisor was developed like a

tusk Tusks are elongated, continuously growing front teeth that protrude well beyond the mouth of certain mammal species. They are most commonly canine tooth, canine teeth, as with Narwhal, narwhals, chevrotains, musk deer, water deer, muntjac, pigs, ...

Phylogeny

The 2018 study that described ''Falcontoxodon'' recovers it, along with ''

Mixotoxodon ''Mixotoxodon'' ("mixture '' Toxodon''") is an extinct genus of notoungulate of the family Toxodontidae inhabiting South America, Central America and parts of southern North America during the Pleistocene epoch, from 1,800,000—12,000 years a ...

'', '' Gyrinodon'' and '' Piauhytherium'', to be in the same monophyletic clade within the subfamily Toxodontinae. Below is a parsimony tree establishing the relationships between the genera of Toxodontidae, as proposed by Carrillo ''et al'', 2018.

Palaeoecology

Paleofauna of the San Gregorio Formation

''Falcontoxodon'' lived in a tropical environment in an area of northern

South America South America is a continent entirely in the Western Hemisphere and mostly in the Southern Hemisphere, with a considerably smaller portion in the Northern Hemisphere. It can also be described as the southern Subregion#Americas, subregion o ...

that was left relatively untouched by the

Great American Interchange The Great American Biotic Interchange (commonly abbreviated as GABI), also known as the Great American Interchange and the Great American Faunal Interchange, was an important late Cenozoic paleozoogeographic biotic interchange event in which land ...

, the only non-native species of mammal known in the area of the Falcón Basin being the

procyonid Procyonidae ( ) is a New World family (biology), family of the order (biology), order Carnivora. It includes the Procyon (genus), raccoons, ringtails, cacomistles, coatis, kinkajous, olingos, and olinguitos. Procyonids inhabit a wide range of e ...

Cyonasua ''Cyonasua'' (meaning "dog-coati" in Greek) is an extinct genus of procyonid from the Late Miocene to Middle Pleistocene of South America. Fossils of ''Cyonasua'' have been found in Argentina ( Ituzaingó, Epecuén, Huayquerías, Monte Hermoso, ...

'' and '' Chapalmalania'', and, potentially, a

Camelidae Camelids are members of the biological family Camelidae, the only currently living family in the suborder Tylopoda. The seven extant members of this group are: dromedary camels, Bactrian camels, wild Bactrian camels, llamas, alpacas, vicuñas ...

still unassigned to a specific genus. Its environment was continental, an open, forested

grassland A grassland is an area where the vegetation is dominance (ecology), dominated by grasses (Poaceae). However, sedge (Cyperaceae) and rush (Juncaceae) can also be found along with variable proportions of legumes such as clover, and other Herbaceo ...

area with

rainforest Rainforests are forests characterized by a closed and continuous tree Canopy (biology), canopy, moisture-dependent vegetation, the presence of epiphytes and lianas and the absence of wildfire. Rainforests can be generally classified as tropi ...

elements, near

freshwater Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mi ...

. It coexisted with pampatheres such as '' Holmesina'' and '' Plaina'',

proterotheriidae Proterotheriidae is an extinction, extinct family of Litopterna, litoptern ungulates known from the Eocene-Late Pleistocene of South America. Members of the group were small-medium sized cursorial Herbivore, herbivores with brachydont Tooth, teet ...

, the

glyptodont Glyptodonts are an extinct clade of large, heavily armoured armadillos, reaching up to in height, and maximum body masses of around 2 tonnes. They had short, deep skulls, a fused vertebral column, and a large bony carapace made up of hundreds o ...

'' Boreostemma'', the

dasypodidae Dasypodidae, from Ancient Greek δασύς (''dasús''), meaning "hair", and πούς (''poús''), meaning "foot", is a family of mostly extinct genera of armadillos. One genus, ''Dasypus'', is extant, with at least seven living species. __TO ...

'' Pliodasypus'' and the

ground sloth Ground sloths are a diverse group of extinct sloths in the mammalian superorder Xenarthra. They varied widely in size with the largest, belonging to genera '' Lestodon'', ''Eremotherium'' and ''Megatherium'', being around the size of elephants. ...

'' Proeremotherium'', as well as several species of

caviomorph Caviomorpha is the rodent parvorder that unites all New World hystricognaths. It is supported by both fossil and molecular evidence. The Caviomorpha was for a time considered to be a separate order outside the Rodentia, but is now accepted as ...

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

s such as '' Caviodon'', '' Hydrochoeropsis'', ''

Marisela Marisela Hernandez (born April 24, 1966, as Marisela Esqueda), commonly known as simply Marisela, is a Mexican-American singer. In 1984, she recorded her first album at the age of 18, and continued to release albums into the 1990s. Her cover ve ...

'' and '' Neoepiblema'', and the

crocodile Crocodiles (family (biology), family Crocodylidae) or true crocodiles are large, semiaquatic reptiles that live throughout the tropics in Africa, Asia, the Americas and Australia. The term "crocodile" is sometimes used more loosely to include ...

'' Crocodylus falconensis.

References

{{Meridiungulata, N., state=autocollapse Toxodonts Pleistocene mammals of South America Pliocene mammals of South America Pleistocene genus extinctions Neogene Venezuela Pleistocene Venezuela Fossils of Venezuela Fossil taxa described in 2018 Prehistoric placental genera