Marcianosuchus
Marcianosuchus is an extinct genus of eucrocopodan archosauriform from the Middle Triassic Plattensandstein Formation of Germany. The genus contains a single species, Marcianosuchus angustifrons, known from a partial disarticulated skeleton. Marcianosuchus represents the first non-archosaurian archosauriform named from Central Europe.
Discovery and naming
The Marcianosuchus holotype specimen, SMNS 91318, was discovered in 1972 by Rupert Wild in talus deposits of the retired Kössig quarry, representing outcrops of the Plattensandstein Formation near Ebhausen in Calw district of Baden-Württemberg, Germany. The specimen consists of an associated, generally disarticulated, skeleton of a single individual. Known material includes several bones of the skull and lower jaws, teeth, pectoral and pelvic girdles, humeri, femora, an incomplete tibia and probable fibula, assorted autopodial bones, cervical, dorsal, and caudal vertebrae, associated osteoderms, ribs, and gastralia.In 2024, Sues, Spiekman & Schoch described Marcianosuchus angustifrons as a new genus and species of archosauriforms based on these fossil remains. The generic name, Marcianosuchus, combines a reference to the Black Forest near the type locality with the Greek σοῦχος, after Sobek, the crocodile-headed ancient Egyptian deity. The specific name, angustifrons, combines the Latin words "angustus", meaning "narrow", and "frons", meaning "forehead", after the holotype skull's narrow frontal region.
Marcianosuchus is the only non-archosaurian archosauriform currently known from Germany's Buntsandstein Group and Central Europe as a whole.
Description
Marcianosuchus was a fairly small archosauriform. The holotype individual was likely not fully mature when it died, so would have been able to grow larger. Its femur was close to, similar to the femur of the euparkeriid "Turfanosuchus" shageduensis. The longest known femur of Euparkeria is only long.Marcianosuchus has a body plan very similar to the similarly aged Euparkeria from South Africa. With the euparkeriid-like Dorosuchus from Russia, Marcianosuchus presents a generally skeletal morphology comparable to the archosaur plesiomorphic condition.
Several generally rectangular osteoderms were found in association with the other skeletal elements of Marcianosuchus. These were interpreted as likely forming a paired row along the midline of the back, as in euparkeriids.