''Ronzotherium'' is an extinct genus of

perissodactyl Odd-toed ungulates, mammals which constitute the taxonomic order Perissodactyla (, ), are animals—ungulates—who have reduced the weight-bearing toes to three (rhinoceroses and tapirs, with tapirs still using four toes on the front legs) ...

mammal from the family

Rhinocerotidae A rhinoceros (; ; ), commonly abbreviated to rhino, is a member of any of the five extant species (or numerous extinct species) of odd-toed ungulates in the family Rhinocerotidae. (It can also refer to a member of any of the extinct species ...

. The name derives from the hill of 'Ronzon', the French locality near Le Puy-en-Velay at which it was first discovered, and the Greek suffix 'therium' meaning 'beast'. At present 5 species have been identified from several localities in

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a subcontinent of Eurasia and it is located enti ...

and

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an ...

, spanning the Late

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

to Upper

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but ...

(37 - 23 million years ago).

Description

''Ronzotherium'' was a small to mid-sized rhinocerotid. Smaller species weighed in the region of 1t, while larger species could reach 1.9t in weight.Damien Becker: ''Earliest record of rhinocerotoids (Mammalia: Perissodactyla) from Switzerland: systematics and biostratigraphy.''Swiss Journal of Geosciences 102, 2009, S. 489–504 The genus was similar in weight to the extant

Black Rhinoceros The black rhinoceros, black rhino or hook-lipped rhinoceros (''Diceros bicornis'') is a species of rhinoceros, native to eastern and southern Africa including Angola, Botswana, Kenya, Malawi, Mozambique, Namibia, South Africa, Eswatini, Tanzania ...

although with an overall more slender and gracile build, with a long humerus and femur in comparison to other rhinocerotids. The genus shows a trend for increased size, with later species being considerably larger than some of its first representatives. ''Ronzotherium'' did not possess a nasal horn. Instead the nasal bones were retracted, suggesting the presence of a large prehensile upper lip like those seen in modern rhinoceros species. The lower incisors of ''Ronzotherium'' were long and tusk- like, with a large diastema in the lower jaw between the incisors and other teeth. The upper incisors were much smaller. The forelimbs of Ronzotherium were tetradactyl with a prominent central metapodal. The hindlimbs however were tridactyl, with three toes.

Classification

Ronzotherium is a basal

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial n ...

within the family rhinocerotidae, one of three families contained within the

superfamily SUPERFAMILY is a database and search platform of structural and functional annotation for all proteins and genomes. It classifies amino acid sequences into known structural domains, especially into SCOP superfamilies. Domains are functional, str ...

rhinocerotoidea Rhinocerotoidea is a superfamily consisting of three family groups of odd-toed ungulates, three of which, the Amynodontidae, Hyracodontidae, and Paraceratheriidae, are extinct. The only extant family group is the Rhinocerotidae (true rhinocerose ...

, along with the

Hyracodontidae The Hyracodontidae are an extinct family of rhinoceroses endemic to North America, Europe, and Asia during the Eocene through early Oligocene, living from 48.6 to 26.3 million years ago (Mya), existing about . The Hyracodontidae thrived in the ...

and

Amynodontidae Amynodontidae ("defensive tooth") is a family of extinct perissodactyls related to true rhinoceroses. They are commonly portrayed as semiaquatic hippo-like rhinos but this description only fits members of the Metamynodontini; other groups of a ...

. The family also contains all 5 extant rhinoceros species. 5 species have been identified within the genus: * ''Ronzotherium velaunum'' (Aymard, 1853) * ''Ronzotherium filholi'' (Osborn, 1900) * ''Ronzotherium romani'' (Kretzoi, 1945) * ''Ronzotherium orientale'' (Dashzeveg, 1991) * ''Ronzotherium brevirostre'' (Beliajeva, 1954) The 3 European species are believed to have dispersed into Europe during the lower

Rupelian The Rupelian is, in the geologic timescale, the older of two ages or the lower of two stages of the Oligocene Epoch/ Series. It spans the time between . It is preceded by the Priabonian Stage (part of the Eocene) and is followed by the Chattian ...

as part of the

Grande Coupure Grande means "large" or "great" in many of the Romance languages. It may also refer to: Places *Grande, Germany, a municipality in Germany * Grande Communications, a telecommunications firm based in Texas * Grande-Rivière (disambiguation) * Arr ...

, and were seemingly widespread in the post-grande coupure fauna of Europe, with fossils discovered in Rupelian deposits from the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the European mainland, continental mainland. It comprises England, Scotlan ...

France France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan ar ...

Germany Germany, officially the Federal Republic of Germany (FRG),, is a country in Central Europe. It is the most populous member state of the European Union. Germany lies between the Baltic and North Sea to the north and the Alps to the sou ...

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...

, Switzerland, and the

Czech Republic The Czech Republic, or simply Czechia, is a landlocked country in Central Europe. Historically known as Bohemia, it is bordered by Austria to the south, Germany to the west, Poland to the northeast, and Slovakia to the southeast. Th ...

. ''Ronzotherium brevirostre'' and ''Ronzotherium'' ''orientale'' are known exclusively from the Late Eocene of

Mongolia Mongolia; Mongolian script: , , ; lit. "Mongol Nation" or "State of Mongolia" () is a landlocked country in East Asia, bordered by Russia to the north and China to the south. It covers an area of , with a population of just 3.3 millio ...

. Further material has been found in the Linxia basin in China's gansu province.Tao Deng: ''Late Cenozoic environmental changes in the Linxia basin (Gansu, China) as indicated by cenograms of fossil Mammals.'' Vertebrata PalAsiatica 47 (4), 2009, S. 282–298

Palaeobiology

Isotope analysis of teeth discovered at Rickenbach in Switzerland has shown that european ''Ronzotherium'' species were adapted to the increasingly drier climate and open landscapes of the post-grande coupure Oligocene. The low crowned dentition suggests that ''Ronzotherium'' was a browser, feeding on the leaves of shrubs, bushes, and small trees.Bastien Mennecart, Laureline Scherler, Florent Hiard, Damien Becker und Jean-Pierre Berger: ''Large mammals from Rickenbach (Switzerland, reference locality MP29, Late Oligocene): biostratigraphic and alaeoenvironmental implications.''Swiss Journal of Geosciences 131 (1), 2012, S. 161–181 This is supported by the presence of the a prehensile upper lip which is used by modern rhinocerotids to browse on foliage. The gracile build and long limb bones found in ''Ronzotherium'' suggest that it could have been capable of sustained running.

Ichnology

Fossil rhinocerotid trackways assigned to the

ichnotaxon An ichnotaxon (plural ichnotaxa) is "a taxon based on the fossilized work of an organism", i.e. the non-human equivalent of an artifact. ''Ichnotaxa'' comes from the Greek ίχνος, ''ichnos'' meaning ''track'' and ταξις, ''taxis'' meaning ...

''Rhinoceripeda voconsense'' (Vialov 1966) have been discovered at two sites in the

Luberon The Luberon ( or ; Provençal: ''Leberon'' or ''Leberoun'' ) is a massif in central Provence in Southern France, part of the French Prealps. It has a maximum elevation of and an area of about . It is composed of three mountain ranges (from wes ...

Natural Regional Park in southeast France. The trackways are preserved in the Calcaires de La Fayette, a

calcareous Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines. In zoology ''Calcareous'' is used as an a ...

lacustrian deposit dating to the lower Rupelian, and are exposed at

Saignon Saignon (; oc, Sanhon) is a commune in the Vaucluse department in the Provence-Alpes-Côte d'Azur region in southeastern France. The nearest town is Apt. There is a bakery/cafe, two restaurants, and a general store. The school has about 100 s ...

and Viens. Various other trackways including

artiodactyls The even-toed ungulates (Artiodactyla , ) are ungulates—hoofed animals—which bear weight equally on two (an even number) of their five toes: the third and fourth. The other three toes are either present, absent, vestigial, or pointing poster ...

and possibly

creodonts Creodonta ("meat teeth") is a former order of extinct carnivorous placental mammals that lived from the early Paleocene to the late Miocene epochs in North America, Europe, Asia and Africa. Originally thought to be a single group of animals an ...

are also present. Based on the 1974 discovery of a ''Ronzotherium velaunum'' mandible in lower Oligocene strata at Viens, the tracks are attributed to ''Ronzotherium''.

Localities

United Kingdom

In the United Kingdom rare isolated teeth and bone fragments, attributed to ''Ronzotherium romani,'' have been found from the Rupelian aged

Bouldnor Formation The Bouldnor Formation is a geological formation in the Hampshire Basin of southern England. It is the youngest formation of the Solent Group and was deposited during the uppermost Eocene and lower Oligocene. Stratotype and occurrence The Boul ...

on the

Isle Of Wight The Isle of Wight ( ) is a Counties of England, county in the English Channel, off the coast of Hampshire, from which it is separated by the Solent. It is the List of islands of England#Largest islands, largest and List of islands of England#Mo ...

. Here ''Ronzotherium'' formed part of the post-grande coupure fauna alongside

anthracotheres Anthracotheriidae is a paraphyletic family of extinct, hippopotamus-like artiodactyl ungulates related to hippopotamuses and whales. The oldest genus, '' Elomeryx'', first appeared during the middle Eocene in Asia. They thrived in Africa and Eura ...

entelodont Entelodontidae, the entelodonts, are an extinct family of pig-like artiodactyls (even-toed ungulates) which inhabited the Northern Hemisphere (Asia, Europe, and North America) from the late Eocene to the Middle Miocene epochs, about 38-19 m ...

s, and a variety of other Asian derived groups.

France

Ronzotherium remains have been recovered from numerous Oligocene sites throughout France. In the Rupelian strata of the Paris Basin material attributed to ''R.romani'' has been collected from Etampes and Ferte-Alais. In south-western France the fossiliferous

Quercy Phosphorites Formation The Quercy Phosphorites Formation (French: ''Phosphorites du Quercy'') is a geologic formation and Lagerstätte in Occitanie, southern France. It preserves fossils dating back to the Paleogene period ( latest Bartonian to Late Oligocene),

has produced Ronzotherium material, including an intact

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The ...

. A large majority of France's ''Ronzotherium'' material comes from the Oligocene deposits of the Luberon Massif, northwest of the city of Marseille. Here fossil trackways and bone fragments of Ronzotherium dating from the early Oligocene have been discovered at the villages of Saignon and Viens. Further south at Les Milles bone fragments and a nearly intact mandible have been collected. Finds have also come from the city of Marseille itself. At Saint-Henri and Saint-Andre in the north of the city 50 fragments of bone and dentition have been recovered, including a mandible and semi-intact upper jaw

Germany

The

Espenhain Espenhain is a village and a former municipality in the Leipzig district, in Saxony, Germany. On 1 August 2015 it was merged into the town Rötha.Saxony Saxony (german: Sachsen ; Upper Saxon: ''Saggsn''; hsb, Sakska), officially the Free State of Saxony (german: Freistaat Sachsen, links=no ; Upper Saxon: ''Freischdaad Saggsn''; hsb, Swobodny stat Sakska, links=no), is a landlocked state of ...

have produced a series of ''Ronzotherium'' teeth. The locality, south of

Leipzig Leipzig ( , ; Upper Saxon: ) is the most populous city in the German state of Saxony. Leipzig's population of 605,407 inhabitants (1.1 million in the larger urban zone) as of 2021 places the city as Germany's eighth most populous, as ...

, exposes the Bohn Formation, a predominantly marine sequence of Rupelian age that has preserved a rich terrestrial fauna of post-grande coupure mammals.

Switzerland

Switzerland preserves the oldest, and some of the youngest evidence of the genus in Europe. At Kleinblauen and

Bressaucourt Bressaucourt is a former municipality in the district of Porrentruy in the canton of Jura in Switzerland. On 1 January 2013 the former municipality of Bressaucourt merged into the municipality of Fontenais. At the late Oligocene locality of Rickenbach 35 fragments of cranial and post-cranial material have been recovered from Chattian strata.

Asia

The late eocene Ergilin-Dzo Formation in Mongolia has produced the remains of two species of ''Ronzotherium''; ''R.brevirostre'' and ''R.orientale.'' This is the earliest known occurrence of the genus, dated at 37 million years ago. Further asian finds come from the Late Oligocene of China's Linxia Basin, where an unspecified species of ''Ronzotherium'' lived alongside a diversity of other late tertiary rhinocerotids.

References

{{Taxonbar, from=Q3388673 Prehistoric placental genera Prehistoric rhinoceroses