Misplaced Pages

Reigitherium Temporal range: Late Cretaceous, Campanian–Maastrichtian PreꞒ Ꞓ O S D C P T J K Pg N
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Clade:	†Meridiolestida
Clade:	†Mesungulatoidea
Family:	†Reigitheriidae Bonaparte, 1990
Genus:	†Reigitherium Bonaparte, 1990
Species:	†R. bunodontum
Binomial name
†Reigitherium bunodontum Bonaparte, 1990

Reigitherium was a mammal that lived during the Late Cretaceous, in the (Late Campanian-Maastrichtian). Its fossils have been found in the Los Alamitos and the La Colonia Formations of Argentina.

Description

The original specimen of Reigitherium was a fragmentary single molar tooth, with a lot of the surface detail damaged. It was mistakenly identified as an upper left molar, but new material - including a whole tooth row of this species - clarifies that it was a lower right tooth.

Reigitherium was a small mammal with simple premolars that increased in size along the tooth row to an enlarged fourth premolar. The molar teeth them decreased in size along the tooth row.

Taxonomy

Reigitherium has proven difficult to classify until recently, because the original fossil material was sparse, damaged, and difficult to identify. It was initially thought to be a dryolestid mammal when described in 1990. Ten years later, Pascual et al. argued that it was a docodont based on the wear patterns they interpreted on the teeth.

In 2011, Rougier et al. argued again for it being a dryolestoid, within Meridiolestida, an order of Gondwanan dryolestoids. More complete fossils have now supported this analysis

A recent phylogenetic study finds it to be the sister taxon to Peligrotherium. Although the latter is much larger than Reigitherium, they share many tooth and skull characteristics that indicate they are closely related.

References

1. ^ Bonaparte, J. F. New Late Cretaceous mammals from the Los-Alamitos formation, Northern Patagonia. National Geographic Research 6.1 63-83.
2. ^ Harper T, Parras A, Rougier GW. 2018. Reigitherium (Meridiolestida, Mesungulatoidea) an enigmatic Late Cretaceous mammal from Patagonia, Argentina: morphology, affinities, and dental evolution. Journal of Mammalian Evolution.
3. Pascual R., Goin F.J., Gonzalez P., Ardolino A. & Puerta P.F. (2000) A highly derived docodont from the Patagonian Late Cretaceous Geodiversitas 22 (3) Documento pdf Archived 2012-04-14 at the Wayback Machine.
4. Guillermo W. Rougier; Sebastián Apesteguía; Leandro C. Gaetano (2011). "Highly specialized mammalian skulls from the Late Cretaceous of South America". Nature. 479 (7371): 98–102. Bibcode:2011Natur.479...98R. doi:10.1038/nature10591. PMID 22051679. S2CID 4380850. Supplementary information

v t e Mammalia
Kingdom: Animalia Phylum: Chordata Clade: Synapsida Clade: Therapsida Clade: Cynodontia Clade: Mammaliaformes Synapsida see Synapsida Cynodontia see Cynodontia Mammalia see below↓
Mammalia Australosphenida? †Ambondro †Tendagurutherium? Monotremata? †Henosferidae Asfaltomylos Henosferus †Ausktribosphenidae Ausktribosphenos Bishops? Kryoparvus? Monotremata †Kollikodontidae? Kollikodon Kryoryctes? Sundrius †Steropodontidae Parvopalus? Steropodon †Teinolophidae Stirtodon? Teinolophos Ornithorhynchoidea †Opalios Ornithorhynchidae †Dharragarra? †Monotrematum? †Obdurodon Ornithorhynchus †Patagorhynchus? Tachyglossidae †Megalibgwilia †Murrayglossus Tachyglossus Zaglossus †Allotheria? see Allotheria includes multituberculates Theriimorpha see below↓
Theriimorpha Theriimorpha †Acinacodus †Amphidon †Amphilestes †Aploconodon †Chaoyangodens †Comodon †Condorodon †Dyskritodon? †Fruitafossor? †Hakusanodon †Indotriconodon †Juchilestes †Jueconodon †Kemchugia †Kryptotherium †Liaoconodon †Liaotherium †Manchurodon †Nakunodon †Phascolotherium †Sangarotherium †Tendagurodon †Allotheria? Monotremata? †Gobiconodontidae Fuxinoconodon Gobiconodon Hangjinia Huasteconodon? Meemannodon Repenomamus Spinolestes †Jeholodentidae Jeholodens Yanoconodon †Klameliidae? Ferganodon Klamelia †Triconodontidae Alticonodon Arundelconodon Astroconodon Corviconodon Eotriconodon Jugulator Meiconodon Priacodon Triconodon Trioracodon Victoriaconodon Volaticotheria? †Volaticotheria Argentoconodon Ichthyoconodon Triconolestes? Volaticotherium †Tinodontidae Gobiotheriodon? Tinodon Trishulotherium Yermakia Trechnotheria Monotremata? †Zhangheotheriidae Anebodon Kiyatherium Maotherium Ningchengodon Origolestes Zhangheotherium †Spalacotheriidae Akidolestes Aliaga Cifellitherium Heishanlestes Infernolestes Lactodens Shalbaatar Spalacolestes Spalacotheridium Spalacotherium Spalacotheroides Symmetrodontoides Symmetrolestes Yaverlestes Cladotheria see below↓
Cladotheria †Dryolestida Brancatherulum? Dorsetodon Drescheratherium Euthlastus Henkelotherium Paurodon Tathiodon Dryolestidae Achyrodon Amblotherium Anthracolestes Beckumia Crusafontia Dryolestes Groebertherium? Guimarotodus Hercynodon Krebsotherium Lakotalestes? Laolestes Minutolestes Phascolestes Portopinheirodon Treslagosodon †Meridiolestida Amarillodon Austrotriconodon Bondesius Casamiquelia Cronopio Groebertherium? Lakotalestes? Leonardus Necrolestes Paraungulatum Quirogatherium Solanutherium Mesungulatoidea Coloniatherium Mesungulatum Orretherium Peligrotherium Reigitherium †Donodontidae Amazighodon Anoualestes Donodon Stylodens Prototribosphenida †Abelodon †Amphibetulimus †Amphitherium †Arguimus †Brancatherulum? †Chunnelodon †Magnimus †Minimus †Mozomus †Nanolestes †Palaeoxonodon †Vincelestes Monotremata? †Peramuridae Afriquiamus? Kouriogenys Peramuroides Peramus Tendagurutherium? Tribosphenida / Boreosphenida †Aegialodon †Argaliatherium †Brasilestes †Carinalestes †Eomaia †Holoclemensia †Hypomylos †Juramaia †Kermackia †Kielantherium †Pappotherium †Picopsis †Tirotherium †Tribactonodon Theria †Patagomaia Eutheria see Eutheria includes placentals Metatheria see Metatheria includes marsupials
Other taxa Incertae sedis †Atlasodon †Chronoperates †Microderson †Thereuodon †Tingamarra Saint Bathans Mammal UA 8699 Other taxa Prototheria Yinotheria Eutriconodonta Amphilestidae Theriiformes Pantotheria Symmetrodonta Eupantotheria Paurodontidae Amphitheriidae Marsupionta

This article about a Cretaceous mammal is a stub. You can help Misplaced Pages by expanding it.

• v
• t
• e

• Meridiolestidans
• Prehistoric mammal genera
• Campanian life
• Maastrichtian life
• Late Cretaceous mammals of South America
• Cretaceous Argentina
• Fossils of Argentina
• Los Alamitos Formation
• Cañadón Asfalto Basin
• Fossil taxa described in 1990
• Taxa named by José Bonaparte
• Cretaceous mammal stubs