''Koilops'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of four-limbed stem-tetrapod from the Mississippian (mid-

Tournaisian The Tournaisian is in the ICS geologic timescale the lowest stage or oldest age of the Mississippian, the oldest subsystem of the Carboniferous. The Tournaisian age lasted from Ma to Ma. It is preceded by the Famennian (the uppermost stage ...

) of

Scotland Scotland (, ) is a country that is part of the United Kingdom. Covering the northern third of the island of Great Britain, mainland Scotland has a border with England to the southeast and is otherwise surrounded by the Atlantic Ocean to the ...

. It contains a single species, ''Koilops herma'', based on a

mold A mold () or mould () is one of the structures certain fungus, fungi can form. The dust-like, colored appearance of molds is due to the formation of Spore#Fungi, spores containing Secondary metabolite#Fungal secondary metabolites, fungal seco ...

of an 8.0 cm (3.1 in.)-long skull from the

Ballagan Formation The Ballagan Formation is a geologic formation in Scotland and England. It preserves fossils dating back to the early part of the Carboniferous period (Tournaisian – early Visean). Its name comes from the "Ballagan Beds" of Ballagan Glen, near ...

. A

phylogenetic analysis In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

in its original description places ''Koilops'' as a close relative of ''

Tulerpeton ''Tulerpeton'' is an extinct genus of Devonian four-limbed vertebrate, known from a fossil that was found in the Tula Region of Russia at a site named Andreyevka. This genus and the closely related ''Acanthostega'' and ''Ichthyostega'' represent ...

'' and colosteids. ''Koilops'' was described in a 2016 study which was devised to fill in the tetrapod and stem-tetrapod faunas of

Romer's gap Romer's gap is an example of an apparent gap in the tetrapod fossil record used in the study of evolutionary biology. Such gaps represent periods from which excavators have not yet found relevant fossils. Romer's gap is named after paleontologist ...

, an interval of the early

Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carbonifero ...

with few vertebrate fossils. It was one of five new genera named in this study, along with ''

Aytonerpeton ''Aytonerpeton'' is an extinct genus of stem-tetrapod from the Ballagan Formation of Scotland. It was one of five new genera of early limbed vertebrates from the Ballagan Formation described by Clack ''et al.'' in 2016. These vertebrates were amo ...

'', ''

Diploradus ''Diploradus'' is an extinct genus of four-limbed stem-tetrapod from the Mississippian (mid- Tournaisian) of Scotland. It contains a single species, ''Diploradus austiumensis'', based on an incomplete skull and jaw fragments from the Ballagan ...

'', ''

Ossirarus ''Ossirarus'' is an extinct genus of four-limbed stem-tetrapod from the Mississippian (mid-Tournaisian) of Scotland. It contains a single species, ''Ossirarus kierani'', based on disarticulated skull and postcranial bones from the Ballagan Form ...

'', and ''

Perittodus ''Perittodus'' is an extinct genus of four-limbed stem-tetrapod from the Mississippian (mid-Tournaisian) of Scotland. It contains a single species, ''Perittodus apsconditus'', based on disarticulated skull and postcranial bones from the Ballaga ...

''.

References

Carboniferous tetrapods of Europe Stegocephalians Mississippian animals Prehistoric tetrapod genera {{Labyrinthodontia-stub Fossil taxa described in 2016