Plagiaulacida is a group of extinct multituberculate mammals. Multituberculates were among the most common mammals of the Mesozoic, "the age of the dinosaurs". Plagiaulacids are a paraphyletic grouping, containing all multituberculates that lie outside of the advanced group Cimolodonta. They ranged from the Middle Jurassic Period to the early Late Cretaceous of the Northern Hemisphere. During the Cenomanian, they were replaced by the more advanced cimolodontans.

Kielan-Jaworowska and Hurum (2001) divides "Plagiaulacida" into three informal lineages, the paulchoffatiids, the plagiaulicids, and the allodontids.

Allodontid line

The Allodontid line may be a superfamily, Allodontoidea.

Both allodontids and paulchoffatiids (below) were among the most basal of the plagiaulacids. The Allodontid line contains:

The family Allodontidae is known from two genera from the Upper Jurassic Morrison Formation of North America.

The family Zofiabaataridae contains a single genus, Zofiabaatar and is also from the Morrison Formation. The affinities of a further Morrison Formation genus, Glirodon, are unclear, but it's also within the Allodontid line.

Paulchoffatiid line

The Paulchoffatiid line may be a superfamily, Paulchoffatioidea.

Some remains from the Middle Jurassic of England might belong within this group. Representatives are best known from the Upper Jurassic, (especially from Guimarota, Portugal), though some were still extant during the Lower Cretaceous.

The genera of the family Paulchoffatiidae are divided into two of subfamilies, plus a couple of harder-to-place individuals: Subfamily Paulchoffatiinae includes Paulchoffatia and its relatives. This taxon contains nine genera. Subfamily Kuehneodontinae consists solely of the genus Kuehneodon, though there are half-a-dozen named species.

Other genera include Angrivarodon, Galveodon, and Sunnyodon, based on teeth from the Lower Cretaceous of Germany, Spain, and England respectively.

Also referable to the paulchoffatiid line, but not the family itself, is the family Pinheirodontidae, which is known from Early Cretaceous teeth found in Iberia and England. As well as Rugosodon from the Middle-Late Jurassic of China.

Plagiaulacid line (possibly Superfamily Plagiaulacoidea)

Family Plagiaulacidae is known from the Upper Jurassic (North America) to Lower Cretaceous (Europe), being represented by Plagiaulax, Bolodon, and Morrisonodon.

Family Albionbaataridae is known from the Upper Jurassic to Lower Cretaceous of Europe and Asia, (China – undescribed, 2001). These were shrew-sized Multituberculates, with some similarities to the paulchoffis.

Members of the family Eobaataridae display dental similarities with members of Paracimexomys group, (Cimolodonta). They are known from the Upper Jurassic to Lower Cretaceous of Europe and Asia.

Sinobaatar was described after the study by Kielan-Jaworowska and Hurum (2001). The Mongolian word 'baatar' is frequently employed in the nomenclature of Multituberculates. This reflects the fact that many of the most complete fossils have been recovered from sites in Mongolia, though this more applies to members of the more derived Cimolodonta.

A couple of further genera possibly fit somewhere within "Plagiaulacida". This has been tentatively proposed for Janumys of the Middle Cretaceous. Its contemporary, Ameribaatar, is of uncertain affinities. Both were first described late in 2001.

Taxonomy Subclass †Allotheria Order †Multituberculata : suborder †Plagiaulacida Family †Paulchoffatiidae subfamily †Paulchoffatiinae Genus †Paulchoffatia Species †P. delgador Genus †Pseudobolodon Species †P. oreas Species †P. krebsi Genus †Henkelodon Species †H. naias Genus †Guimarotodon Species †G. leiriensis Genus †Meketibolodon Species †M. robustus Genus †Plesiochoffatia Species †P. thoas Species †P. peparethos Species †P. staphylos Genus †Xenachoffatia Species †X. oinopion Genus †Bathmochoffatia Species †B. hapax Genus †Kielanodon Species †K. hopsoni Genus †Meketichoffatia Species †M. krausei Genus †Galveodon Species †G. nannothus Genus †Sunnyodon Species †S. notleyi Subfamily †Kuehneodontinae Genus †Kuehneodon Species †K. dietrichi Species †K. barcasensis Species †K. dryas Species †K. guimarotensis Species †K. hahni Species †K. simpsoni Species †K. uniradiculatus Family †Pinheirodontidae Genus †Pinheirodon Species †P. pygmaeus Species †P. vastus Genus †Bernardodon Species †B. atlantica Genus †Gerhardodon Species †G. purbeckensis Genus †Iberodon Species †I. quadrituberculatus Genus †Lavocatia Species †L. alfambrensis Genus †Ecprepaulax Species †E. anomala Family †Allodontidae Genus †Ctenacodon Species †C. serratus Species †C. nanus Species †C. laticeps Species †C. scindens Genus †Psalodon Species †P. potens Species †P. fortis Species †P. marshi Family †Zofiabaataridae Genus †Zofiabaatar Species †Z. pulcher Family Incertae sedis Genus †Glirodon Species †G. grandis Family †Plagiaulacidae Genus †Morrisonodon Species †M. brentbaatar Genus †Plagiaulax Species †P. becklesii Genus †Bolodon Species †B. crassidens Species †B. falconeri Species †B. minor Species †B. osborni Species †B. elongatus Family †Eobaataridae Genus †Eobaatar Species †E. magnus Species †E. minor Species †E. hispanicus Species †E. pajaronensis Genus †Loxaulax Species †L. valdensis Genus †Monobaatar Species †M. mimicus Genus †Parendotherium Species †Parendotherium herreroi Genus †Sinobaatar Species †Sinobaatar lingyuanensis Genus †Heishanobaatar Species †H. triangulus Genus †Teutonodon Species †Teutonodon langenbergensis Family †Albionbaataridae Genus †Albionbaatar Species †A. denisae Genus †Proalbionbaatar Species †P. plagiocyrtus Genus †Kielanobaatar Species †K. badaohaoensis Family †Arginbaataridae Genus †Arginbaatar Species †Arginbaatar dmitrievae

Phylogeny Cladogram after Carvalho et al. 2025:

References

Hahn G & Hahn R (2000), Multituberculates from the Guimarota mine, p. 97-107 in Martin T & Krebs B (eds), Guimarota - A Jurassic Ecosystem, Published by Dr Friedrich Pfeil, Münich, Germany. Kielan-Jaworowska Z & Hurum JH (2001), Phylogeny and Systematics of multituberculate mammals. Paleontology 44, p. 389-429. Much of this information has been derived from Multituberculata Cope, 1884.