''Stephanorhinus'' is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

genus of two-horned

rhinoceros A rhinoceros ( ; ; ; : rhinoceros or rhinoceroses), commonly abbreviated to rhino, is a member of any of the five extant taxon, extant species (or numerous extinct species) of odd-toed ungulates (perissodactyls) in the family (biology), famil ...

native to

Eurasia Eurasia ( , ) is a continental area on Earth, comprising all of Europe and Asia. According to some geographers, Physical geography, physiographically, Eurasia is a single supercontinent. The concept of Europe and Asia as distinct continents d ...

and North Africa that lived during the

Late Pliocene Late or LATE may refer to: Everyday usage * Tardy, or late, not being on time * Late (or the late) may refer to a person who is dead Music * Late (The 77s album), ''Late'' (The 77s album), 2000 * Late (Alvin Batiste album), 1993 * Late!, a pseudo ...

Late Pleistocene The Late Pleistocene is an unofficial Age (geology), age in the international geologic timescale in chronostratigraphy, also known as the Upper Pleistocene from a Stratigraphy, stratigraphic perspective. It is intended to be the fourth division ...

. Species of ''Stephanorhinus'' were the predominant and often only species of rhinoceros in much of temperate Eurasia, especially Europe, for most of the Pleistocene. The last two species of ''Stephanorhinus'' – Merck's rhinoceros (''S. kirchbergensis'') and the narrow-nosed rhinoceros (''S. hemitoechus'') – went extinct during the last glacial period.

Etymology

The first part of the name, ''Stephano-'', honours Stephen I, the first king of Hungary. (The genus name was coined by Kretzoi, a Hungarian.) The second part is from (Greek for "nose"), a typical suffix of rhinoceros genus names.

Taxonomy

The taxonomic history of ''Stephanorhinus'' is long and convoluted, as many species are known by numerous synonyms and different genera – typically ''Rhinoceros'' and '' Dicerorhinus'' – for the 19th and most of the early 20th century. The genus was named by

Miklós Kretzoi Miklós Kretzoi (9 February 1907 – 15 March 2005) was a Hungarian people, Hungarian geologist, paleontologist and paleoanthropologist and Széchenyi Prize winner. Exhibition in the Hungarian National Museum, 9 February - 24 May 2004 Kr ...

in 1942.Miklós Kretzoi:
Bemerkungen zur System der Nachmiozänen Nashorn-Gattungen (Comments on the system of the post Miocene rhinoceros genera)
' Földtani Közlöni, Budapest 72 (4-12), 1942, S. 309–318 Genomes obtained from ''Stephanorhinus kirchbergensis'' suggests that ''Stephanorhinus'' is more closely related to '' Dicerorhinus'' (which contains the living Sumatran rhinoceros) and '' Coelodonta'' (which contains the woolly rhinoceros), than it is to other living rhinoceroses, and is more closely related to ''Coelodonta'' than to ''Dicerorhinus,'' with the date of

divergence In vector calculus, divergence is a vector operator that operates on a vector field, producing a scalar field giving the rate that the vector field alters the volume in an infinitesimal neighborhood of each point. (In 2D this "volume" refers to ...

between ''Coelodonta'' and ''Stephanorhinus'' estimated at around 5.5 million years ago, with the estimated split between their last common ancestor and ''Dicerorhinus'' estimated at around 9.4 million years ago. The genus is also closely related to the fossil rhinoceros genera '' Dihoplus'' and '' Pliorhinus'', known from the Late Miocene and Pliocene of Eurasia, which may be ancestral to ''Stephanorhinus''. Although a study based on dental proteomes suggested that the genus was

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

with respect to ''Coelodonta'', a 2023 morphological study recovered ''Stephanorhinus'' as

monophyletic In biological cladistics for the classification of organisms, monophyly is the condition of a taxonomic grouping being a clade – that is, a grouping of organisms which meets these criteria: # the grouping contains its own most recent co ...

. Placement of ''Stephanorhinus kirchbergensis'' among recent and subfossil rhinoceros species based on nuclear genomes (Liu, 2021): Bayesian morphological phylogeny (Pandolfi, 2023) Note: This excludes living African rhinoceros species.

Description

Species of ''Stephanorhinus'' were large-sized rhinoceroses, with body masses estimated between . ''Stephanorhinus'' species have proportionally long (dolichocephalic) skulls. They had two horns, a frontal and a nasal horn. The

nasal septum The nasal septum () separates the left and right airways of the Human nose, nasal cavity, dividing the two nostrils. It is Depression (kinesiology), depressed by the depressor septi nasi muscle. Structure The fleshy external end of the nasal s ...

was partially

ossified Ossification (also called osteogenesis or bone mineralization) in bone remodeling is the process of laying down new bone material by cells named osteoblasts. It is synonymous with bone tissue formation. There are two processes resulting in t ...

(turned to bone), which connected the nasal bones with the premaxillary bones. The incisors were either lost completely or very heavily reduced in size.

Species and evolution

The oldest known species of the genus are from the

Pliocene The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58Dihoplus'' and '' Pliorhinus'', respectively. “''Stephanorhinus''” ''miguelcrusafonti'' from the

Early Pliocene Early may refer to: Places in the United States * Early, Iowa, a city * Early, Texas, a city * Early Branch, a stream in Missouri * Early County, Georgia * Fort Early, Georgia, an early 19th century fort Music * Early B, stage name of Jamaican d ...

of Western Europe has also been assigned to ''Pliorhinus'' in recent studies. The position of ''Stephanorhinus''? ''africanus'' from the Middle Pliocene of Tunisia and Chad is uncertain. Some authors have suggested that ''Stephanorhinus'' likely originated from members of the genus ''Pliorhinus''. ''Stephanorhinus jeanvireti,'' also known as ''S. elatus'' is known from the Late Pliocene and

Early Pleistocene The Early Pleistocene is an unofficial epoch (geology), sub-epoch in the international geologic timescale in chronostratigraphy, representing the earliest division of the Pleistocene Epoch within the ongoing Quaternary Period. It is currently esti ...

of Europe. Its remains are relatively rare in comparison to other ''Stephanorhinus'' species. Specimens are known from the Late Pliocene of Germany, France, Italy, Slovakia and Greece, and the Early Pleistocene of Romania, with its temporal span being around 3.4 to 2 million years ago (Ma). ''Stephanorhinus etruscus'' first appears in the latest Pliocene in the Iberian Peninsula, around 3.3 Ma at Las Higueruelas in Spain and before 3 Ma at Piedrabuena, and during the latest Pliocene at Villafranca d’Asti and Castelnuovo di Berardenga in Italy and is abundant during most of the Villafranchian period in Europe, and is the sole rhinoceros species in Europe between 2.5 and around 1.3 Ma. A specimen is known from the Early Pleistocene (1.6-1.2 Ma) Ubeidiya locality in Israel. During the late Early Pleistocene, it is largely replaced by ''S. hundsheimensis''. The last known records of the species are from the latest Early Pleistocene of the Iberian peninsula, around 0.9-0.8 Ma. ''Stephanorhinus etruscus'' is thought to have had a

browsing Browsing is a kind of orienting strategy. It is supposed to identify something of relevance for the browsing organism. In context of humans, it is a metaphor taken from the animal kingdom. It is used, for example, about people browsing open sh ...

based diet. Remains of ''Stephanorhinus'' not assigned to species have been reported from the Dmanisi site in the

Caucasus The Caucasus () or Caucasia (), is a region spanning Eastern Europe and Western Asia. It is situated between the Black Sea and the Caspian Sea, comprising parts of Southern Russia, Georgia, Armenia, and Azerbaijan. The Caucasus Mountains, i ...

(Georgia), dating to around 1.8 Ma. The remains appear to belong to two morphotypes, which may represent distinct species. Some of these remains may be closely related to the later species ''Stephanorhinus hundsheimensis.'' ''Stephanorhinus hundsheimensis'' first definitively appears in the fossil record in Europe and

Anatolia Anatolia (), also known as Asia Minor, is a peninsula in West Asia that makes up the majority of the land area of Turkey. It is the westernmost protrusion of Asia and is geographically bounded by the Mediterranean Sea to the south, the Aegean ...

at around 1.2 Ma, with possible records in Iberia around 1.6 Ma and 1.4-1.3 Ma. The earliest confirmed appearance in Italy around 1 Ma. The diet of ''S. hundsheimensis'' was flexible and ungeneralised, with two different early Middle Pleistocene populations under different climatic regimes having tooth wear analyses suggesting contrasting

and

grazing In agriculture, grazing is a method of animal husbandry whereby domestic livestock are allowed outdoors to free range (roam around) and consume wild vegetations in order to feed conversion ratio, convert the otherwise indigestible (by human diges ...

habits. ''Stephanorhinus hundsheimensis'' is typically suggested to have gone extinct at around 0.5 Ma, though a 2023 study suggested that the species may have persisted as recently as the latest Middle Pleistocene-earliest Late Pleistocene around 130,000 years ago, based on fossils found in Spain. ''Stephanorhinus'' migrated from its origin in western Eurasia into eastern Eurasia during the

, with remains of ''Stephanorhinus'' including those of ''S. etruscus'' being known from the Early Pleistocene of Kazakhstan and Tajikistan in Central Asia, with the earliest remains of the genus in China dating to around 1.6 Ma. ''Stephanorhinus yunchuchenensis'' is known from a single specimen in probably late Early Pleistocene aged deposits in Yushe,

Shaanxi Shaanxi is a Provinces of China, province in north Northwestern China. It borders the province-level divisions of Inner Mongolia to the north; Shanxi and Henan to the east; Hubei, Chongqing, and Sichuan to the south; and Gansu and Ningxia to t ...

, China, while ''Stephanorhinus lantianensis'' is also known from a single specimen from late Early Pleistocene (1.15 Ma) deposits in Lantian, also in Shaanxi. These may be synonymous with other named ''Stephanorhinus'' species, with a 2022 study suggesting that they were likely synonyms of ''S. kirchbergensis'' and ''S. etruscus'' respectively. The first definitive record of '' Stephanorhinus kirchbergensis'' (Merck's rhinoceros) is in China at Zhoukoudian (Choukoutien; near Beijing), around the Early–Mid-Pleistocene transition at 0.8 Ma. Stephanorhinus_kirchbergensis_range_map

''S. kirchbergensis'' appeared in Europe between 0.7-6 Ma with '' S. hemitoechus'' (the narrow-nosed rhinoceros) first appearing in Europe around 0.6-0.5 Ma. ''S. kirchbergensis'' and ''S. hemitoechus'' are typically interpreted mixed feeders tending towards browsing and grazing, respectively. The evolution of more specialized diets is possibly due to the change to the 100 Kyr cycle after the Mid-Pleistocene Transition, which resulted in environmental stability allowing the development of more specialized forms. ''S. kirchbergensis'' was broadly distributed over northern Eurasia from Western Europe to East Asia, while ''S. hemitoechus'' was generally confined to the western

Palearctic The Palearctic or Palaearctic is a biogeographic realm of the Earth, the largest of eight. Confined almost entirely to the Eastern Hemisphere, it stretches across Europe and Asia, north of the foothills of the Himalayas, and North Africa. Th ...

, including Europe, West Asia, and North Africa.Diana Pushkina: ''The Pleistocene easternmost distribution in Eurasia of the species associated with the Eemian'' Palaeoloxodon antiquus ''assemblage.'' Mammal Review, 2007. Volume 37 Issue 3, Pages 224 - 245Pierre Olivier Antoine: ''Pleistocene and holocene rhinocerotids (Mammalia, Perissodactyla) from the Indochinese Peninsula.'' In: ''Comptes Rendus Palevol.'' 2011, S. 1–10. In Europe, the timing of the extinction of ''S. kirchbergensis'' is uncertain, though it is sometime after 115,000 years ago. The latest records of ''S. hemitoechus'' in Europe are known from the Iberian Peninsula, where they survived until at least 34,000 years ago, with the species possibly surviving as late as 15,500 years ago in the

Levant The Levant ( ) is the subregion that borders the Eastern Mediterranean, Eastern Mediterranean sea to the west, and forms the core of West Asia and the political term, Middle East, ''Middle East''. In its narrowest sense, which is in use toda ...

. In the Altai region, ''S. kirchbergensis'' survived until at least 40,000 years ago. In South China, the species may have survived into Marine Isotope Stage 2 (~29-14,000 years ago).

Relationship with humans

Remains of ''Stephanorhinus'' species have been found in sites across Europe with break or cut marks indicating that they were butchered by

archaic humans ''Homo'' () is a genus of great ape (family Hominidae) that emerged from the genus ''Australopithecus'' and encompasses only a single extant species, ''Homo sapiens'' (modern humans), along with a number of extinct species (collectively calle ...

. The earliest such site is Vallonnet Cave in France dating to around 1.2 to 1.1 million years ago, where remains of ''S. hundsheimensis'' have been reported with cut marks. Another early site is

Boxgrove Boxgrove is a village, parish, ecclesiastical parish and civil parishes in England, civil parish in the Chichester (district), Chichester District of the English county of West Sussex, about north east of the city of Chichester. The village is ...

in England, dating to around 500,000 years ago, where an indeterminate species of ''Stephanorhinus'' was found with cut marks thought to have been created by ''

Homo heidelbergensis ''Homo heidelbergensis'' is a species of archaic human from the Middle Pleistocene of Europe and Africa, as well as potentially Asia depending on the taxonomic convention used. The species-level classification of ''Homo'' during the Middle Pleis ...

''. The youngest sites are known from the late Middle Paleolithic (around 100-40,000 years ago), which were created by

Neanderthals Neanderthals ( ; ''Homo neanderthalensis'' or sometimes ''H. sapiens neanderthalensis'') are an extinction, extinct group of archaic humans who inhabited Europe and Western and Central Asia during the Middle Pleistocene, Middle to Late Plei ...

. At some sites hunting is suggested to be the more likely than scavenging based on mortality profiles. An astragalus attributed to ''Stephanorhinus'' was discovered in the Southwest Quarter of

Mycenae Mycenae ( ; ; or , ''Mykē̂nai'' or ''Mykḗnē'') is an archaeological site near Mykines, Greece, Mykines in Argolis, north-eastern Peloponnese, Greece. It is located about south-west of Athens; north of Argos, Peloponnese, Argos; and sou ...

, along with a collection of other artifacts. Its placement there was dated to the thirteenth century B.C.E, long after the extinction of ''Stephanorhinus''. This is suggested to represent one of the earliest examples of fossil collecting.

References

{{Taxonbar, from=Q14551210 Dicerorhinini Pleistocene rhinoceroses Pleistocene genus extinctions Prehistoric mammals of Europe Pleistocene mammals of Asia Fossil taxa described in 1942 Taxa named by Miklós Kretzoi