chthonosaurus

{{short description|Extinct genus of therapsids from the Late Permian of Russia}}

{{Automatic taxobox

| fossil_range = Late Permian
~{{fossil range|260|253}}

| image = Chthonosaurus velocidens.jpg

| image_caption = Life restoration of Chthonosaurus velocidens

| taxon = Chthonosaurus

| authority = Vjuschkov 1955

| type_species = {{extinct}}Chthonosaurus velocidens

| type_species_authority = Vjuschkov 1955

}}

Chthonosaurus is an extinct genus of eutherocephalian{{Cite journal | last1 = Huttenlocker | first1 = Adam K. | last2 =Sidor | first2 = Christian A. | last3 = Angielczyk | first3 = Kenneth D. | date = 20 Jul 2015 | title = A new eutherocephalian (Therapsida, Therocephalia) from the upper Permian Madumabisa Mudstone Formation (Luangwa Basin) of Zambia | journal = Journal of Vertebrate Paleontology | volume = 35 | issue = 5 | pages = e969400 | doi = 10.1080/02724634.2015.969400| bibcode = 2015JVPal..35E9400H | s2cid = 83554630 | url = https://figshare.com/articles/journal_contribution/1488656 }} therapsids from the Late Permian Kutulukskaya Formation of Russia. The type species Chthonosaurus velocidens was named in 1955.{{cite journal |last=Ivakhnenko |first=M.F. |year=2011 |title=Permian and Triassic therocephals (Eutherapsida) of Eastern Europe |journal=Paleontological Journal |volume=45 |issue=9 |pages=981–1144 |doi=10.1134/S0031030111090012|s2cid=128958135 }}