Breviceratops

Breviceratops is a genus of protoceratopsid dinosaur that inhabited the Earth during the Late Cretaceous period. Its fossils have been discovered in what is now the Barun Goyot Formation in Mongolia. The dinosaur's name, "short horned face," aptly describes some of its key anatomical features.

Discovery and Naming

The initial fossil discoveries of Breviceratops occurred in the 1960s during a Polish expedition to the Nemegt Basin of the Gobi Desert. These specimens were first described in 1975 by Teresa Maryańska and Halszka Osmólska, who initially classified them as a second species of Protoceratops, naming it Protoceratops kozlowskii in honor of Roman Kozłowski. The holotype specimen, ZPAL MgD-I/117, was unearthed from the Khulsan locality and consists of a partial juvenile skeleton with a skull. Other referred specimens were found at the Hermiin Tsav and Khulsan localities.

In 1990, Sergei Mikhailovich Kurzanov reclassified these fossils, establishing Breviceratops as a distinct genus. He combined the Latin word "brevis" (short) with a reference to the Ceratopsia group. Kurzanov also referred additional fossils from Hermiin Tsav, the type locality of Bagaceratops, a contemporary protoceratopsid. However, the close resemblance of these referred fossils to Bagaceratops led to suggestions that Breviceratops might represent a juvenile stage or synonym of Bagaceratops. Nevertheless, the holotype from Khulsan exhibits primitive premaxillary teeth, a characteristic inconsistent with the derived morphology of Bagaceratops. Consequently, most of the previously referred specimens have been re-identified as belonging to Bagaceratops, with Breviceratops now primarily recognized through its holotype and one other specimen (ZPAL MgD-I/116).

Description and Classification

Breviceratops possessed a skull that exhibited a mix of primitive and derived traits. Notable features included premaxillary teeth, a characteristic also found in Protoceratops andrewsi, and an antorbital fenestra – an opening in the maxilla located in front of the eye socket. This fenestra in Breviceratops was distinct from that of Bagaceratops, being narrow to straight-shaped. The skull concluded with a moderately pronounced neck frill, formed by the parietal and squamosal bones, a common feature among protoceratopsids and ceratopsians in general.

Breviceratops has been classified within the Ceratopsia, a diverse group of herbivorous dinosaurs known for their parrot-like beaks that flourished across North America and Asia during the Cretaceous period. In 2019, Łukasz Czepiński assigned Breviceratops to the family Protoceratopsidae, placing it as a close relative to genera like Bagaceratops and Protoceratops.