''Bisticeratops'' (meaning "

Bisti/De-Na-Zin Wilderness The Bisti/De-Na-Zin Wilderness is a wilderness area located in San Juan County in the U.S. state of New Mexico. Established in 1984, the Wilderness is a desolate area of steeply eroded badlands managed by the Bureau of Land Management, ex ...

horned face") is a

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 nom ...

chasmosaurine Chasmosaurinae is a subfamily of ceratopsid dinosaurs. They were one of the most successful groups of herbivores of their time. Chasmosaurines appeared in the early Campanian, and became extinct, along with all other non- avian dinosaurs, durin ...

ceratopsian from outcrops of the

Campanian The Campanian is the fifth of six ages of the Late Cretaceous Epoch on the geologic timescale of the International Commission on Stratigraphy (ICS). In chronostratigraphy, it is the fifth of six stages in the Upper Cretaceous Series. Campani ...

age

Kirtland Formation The Kirtland Formation (originally the Kirtland Shale) is a sedimentary geological formation. Description The Kirtland Formation is the product of alluvial muds and overbank sand deposits from the many channels draining the coastal plain th ...

found in the Bisti/De-Na-Zin Wilderness in northwestern

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe , LargestCity = Albuquerque , LargestMetro = Tiguex , OfficialLang = None , Languages = English, Spanish ( New Mexican), Navajo, Ke ...

, United States. The type and only

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

is ''B. froeseorum'', known from a nearly complete skull.

Discovery and naming

The ''Bisticeratops''

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of sever ...

specimen, NMMNH P-50000, was discovered in 1975 in layers of the

(Farmington Member) in the

area of

San Juan Basin The San Juan Basin is a geologic structural basin located near the Four Corners region of the Southwestern United States. The basin covers 7,500 square miles and resides in northwestern New Mexico, southwestern Colorado, and parts of Utah ...

, northwestern

, United States, which dates to the late

age of the late Cretaceous period. The specimen consists of a mostly complete

skull The skull is a bone protective cavity for the brain. The skull is composed of four types of bone i.e., cranial bones, facial bones, ear ossicles and hyoid bone. However two parts are more prominent: the cranium and the mandible. In humans, th ...

, missing the parietal, left

squamosal The squamosal is a skull bone found in most reptiles, amphibians, and birds. In fishes, it is also called the pterotic bone. In most tetrapods, the squamosal and quadratojugal bones form the cheek series of the skull. The bone forms an ancestral co ...

, postorbital horncores (only the cast of the right postorbital horncore is preserved), left

jugal The jugal is a skull bone found in most reptiles, amphibians and birds. In mammals, the jugal is often called the malar or zygomatic. It is connected to the quadratojugal and maxilla, as well as other bones, which may vary by species. Anatomy ...

, left quadrate,

predentary Ornithischia () is an extinct order of mainly herbivorous dinosaurs characterized by a pelvic structure superficially similar to that of birds. The name ''Ornithischia'', or "bird-hipped", reflects this similarity and is derived from the Greek st ...

, and both dentaries. The holotype specimen was originally thought to be a specimen of ''

Pentaceratops ''Pentaceratops'' ("five-horned face") is a genus of herbivorous ceratopsid dinosaur from the late Cretaceous Period of what is now North America. Fossils of this animal were first discovered in 1921, but the genus was named in 1923 when its ty ...

'', despite being two million years younger than other specimens of that genus. When the description of '' Sierraceratops'' was initially published online in 2021, the name "Bisticeratops froeseorum" was leaked in a cladogram, but edited out when physically published in early 2022. ''Bisticeratops froeseorum'' was formally described by Dalman ''et al''. in a separate paper published the same year. The generic name, "''Bisticeratops''", combines "Bisti", a reference to the location where the holotype was discovered, with the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

''keras'' (meaning "horn"), and ''ops'' (meaning "face"). The specific name honors Edgar Froese, the founder of the band

Tangerine Dream Tangerine Dream is a German electronic music band founded in 1967 by Edgar Froese. The group has seen many personnel changes over the years, with Froese having been the only constant member until his death in January 2015. The best-known lineup ...

, and his son

Jerome Jerome (; la, Eusebius Sophronius Hieronymus; grc-gre, Εὐσέβιος Σωφρόνιος Ἱερώνυμος; – 30 September 420), also known as Jerome of Stridon, was a Christian priest, confessor, theologian, and historian; he is co ...

, former member of Tangerine Dream and founder of the band Loom. Their music is said to have "provided through the years" and inspired the description. Bisticeratops Life Reconstruction

Classification

Using the same

phylogenetic analyses 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 ...

used to find the position of '' Sierraceratops'', Dalman ''et al''. (2022) recovered ''Bisticeratops'' as a sister taxon to an unnamed ceratopsian from the Almond Formation. The

cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ...

below displays the results of the

phylogenetic 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 ...

analyses by Dalman, Jasinski, & Lucas.

Paleobiology

The holotype preserves bite marks from tyrannosaurids, some of which show signs of healing.

Paleoenvironment

The fossil remains of ''Bisticeratops'' were recovered from the Farmington Member of the

. This area represents the product of alluvial muds and overbank sand deposits from the many channels draining the coastal plain that existed on the inland seashore of North America during the late Cretaceous period. No other dinosaurs have been described from the Farmington Member, but taxa from other sub-units include kritosaurin and

lambeosaurine Lambeosaurinae is a group of crested hadrosaurid dinosaurs. Classification Lambeosaurines have been traditionally split into the tribes or clades Parasaurolophini ('' Parasaurolophus'', ''Charonosaurus'', others (?).) and Lambeosaurini (''Cor ...

hadrosaurs, ankylosaurids, chasmosaurine ceratopsids, pachycephalosaurids,

dromaeosaurids Dromaeosauridae () is a family of feathered theropod dinosaurs. They were generally small to medium-sized feathered carnivores that flourished in the Cretaceous Period. The name Dromaeosauridae means 'running lizards', from Greek ('), meaning ...

, an indeterminate

ornithomimid Ornithomimidae (meaning "bird-mimics") is a family of theropod dinosaurs which bore a superficial resemblance to modern ostriches. Ornithomimids were fast, omnivorous or herbivorous dinosaurs known mainly from the Late Cretaceous Period of Laura ...

, tyrannosauroids, azhdarchids,

crurotarsans Crurotarsi is a clade of archosauriform reptiles that includes crocodilians and stem-crocodilians and possibly bird-line archosaurs too if the extinct, crocodile-like phytosaurs are more distantly related to crocodiles than traditionally thoug ...

turtles Turtles are an order of reptiles known as Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked tur ...

, and

cartilaginous Cartilage is a resilient and smooth type of connective tissue. In tetrapods, it covers and protects the ends of long bones at the joints as articular cartilage, and is a structural component of many body parts including the rib cage, the neck a ...

and bony fish from the De-Na-Zin and Hunter Wash members.

References

{{Taxonbar, from=Q113534609 Fossil taxa described in 2022 Chasmosaurines Late Cretaceous dinosaurs of North America Campanian genus first appearances Campanian genus extinctions Ornithischian genera Campanian life