''Peramus'' is an extinct genus of

cladotheria Cladotheria is a clade (sometimes ranked as a legion) of mammals. It contains modern therian mammals (marsupials and placentals) and several extinct groups, such as the "dryolestoids", amphitheriids and peramurids. The clade was named in 1975 ...

n mammal. It lived in the

Late Jurassic The Late Jurassic is the third Epoch (geology), epoch of the Jurassic Period, and it spans the geologic time scale, geologic time from 161.5 ± 1.0 to 143.1 ± 0.8 million years ago (Ma), which is preserved in Upper Jurassic stratum, strata.Owen ...

and

Early Cretaceous The Early Cretaceous (geochronology, geochronological name) or the Lower Cretaceous (chronostratigraphy, chronostratigraphic name) is the earlier or lower of the two major divisions of the Cretaceous. It is usually considered to stretch from 143.1 ...

of Europe and North Africa.

Species

There are three known extinct species in the genus: * ''Peramus dubius''

Lulworth Formation The Lulworth Formation is a geologic formation in England. It dates from the late Tithonian to the mid Berriasian. It is a subunit of the Purbeck Group. In Dorset, it consists of three members, which are in ascending order, the Mupe Member, the ...

, United Kingdom,

Berriasian In the geological timescale, the Berriasian is an age/ stage of the Early/Lower Cretaceous. It is the oldest subdivision in the entire Cretaceous. It has been taken to span the time between 143.1 ±0.6 Ma and 137.05 ± 0.2 (million years ago) ...

* ''Peramus minor'' Lulworth Formation, United Kingdom, Berriasian * ''Peramus tenuirostris'' Lulworth Formation, United Kingdom, Berriasian Additionally, indeterminate remains are known from the

Ksar Metlili Formation The Ksar Metlili Formation is a geological formation in eastern High Atlas of Morocco, it is late Tithonian to Berriasian in age. It is approximately thick and primarily consists of mudstone and sandstone, with thin calcareous beds. One of these ...

of Morocco, dating to the

Tithonian In the geological timescale, the Tithonian is the latest age (geology), age of the Late Jurassic Epoch and the uppermost stage (stratigraphy), stage of the Upper Jurassic Series. It spans the time between 149.2 ±0.7 annum, Ma and 143.1 ±0.6 (mi ...

-Berriasian, and the

Angeac-Charente bonebed The Angeac-Charente bonebed is a fossil deposit located near Angeac-Charente in western France. It dates to the Berriasian stage of the Early Cretaceous, and is coeval with the Purbeck Group of Southern England. It has amongst the most diverse asse ...

in France, dating to the Berriasian.Ronan Allain, Romain Vullo, Lee Rozada, Jérémy Anquetin, Renaud Bourgeais, et al.
Vertebrate paleobiodiversity of the Early Cretaceous (Berriasian) Angeac-Charente Lagerstätte (southwestern France): implications for continental faunal turnover at the J/K boundary
Geodiversitas, Museum National d’Histoire Naturelle Paris, In press. ffhal-03264773f

Phylogeny

''Peramus'' is generally considered an advanced

n. In the analysis performed by Panciroli and colleagues (2018), ''Peramus'' was recovered as within a clade also including ''

Palaeoxonodon ''Palaeoxonodon'' is an extinct genus of cladotherian mammal from the Middle Jurassic of England and Scotland. Discovery The first fossils of ''Palaeoxonodon ooliticus'' were found in the "Mammal Bed" in Kirtlington Quarry, Oxfordshire, Englan ...

'' and ''

Amphitherium ''Amphitherium'' is an extinct genus of stem cladotherian mammal that lived during the Middle Jurassic of England. It was one of the first Mesozoic mammals ever described. A recent phylogenetic study found it to be the sister taxon of '' Palae ...

,'' as derived members of

Cladotheria Cladotheria is a clade (sometimes ranked as a legion) of mammals. It contains modern therian mammals (marsupials and placentals) and several extinct groups, such as the "dryolestoids", amphitheriids and peramurids. The clade was named in 1975 ...

. ''Peramus'', ''Palaeoxonodon'' and ''Amphitherium'' were united by the shared traits of "convergence of the Meckel’s sulcus with the ventral border of the mandible; and possessing open rooted postcanines." but the placement of ''Peramus'' as a more advanced cladotherian cannot be ruled out. In a 2018 analysis by Bi and colleagues, Peramus was recovered in a clade with ''Palaeoxonodon'' and ''

Nanolestes ''Nanolestes'' is an extinct genus of mammals in the order Amphitheriida from the Late Jurassic of Eurasia. Two species, ''N. krusati'' and ''N. drescherae'' are known from the Alcobaça Formation in Portugal. Another species, ''N. mackennai'', ...

'' also as advanced cladotherians. In a 2022 study of cladotherian relationships, it was recovered as a member of

Zatheria Cladotheria is a clade (sometimes ranked as a Legion (taxonomy), legion) of mammals. It contains modern therian mammals (marsupials and Placentalia, placentals) and several extinct groups, such as the "dryolestoids", amphitheriids and peramurids. ...

, closer to Theria than either ''Palaeoxonodon'' and ''

.''

References

Peramuridae Prehistoric mammal genera Tithonian genus first appearances Berriasian genus extinctions Late Jurassic mammals of Africa Early Cretaceous mammals of Europe Taxa named by Richard Owen Fossil taxa described in 1871 {{Cretaceous-mammal-stub