ammonites
Leiostegium tyboensis Ross, Jr. 1970 (trilobite)

Trilobita - Corynexochida - Leiostegiidae

Full reference: R. J. Ross, Jr. 1970. Ordovician Brachiopods, Trilobites, and Stratigraphy in Eastern and Central Nevada. United States Geological Survey Professional Paper 639

Belongs to Leiostegium according to R. J. Ross 1970

Sister taxa: Leiostegium formosa, Leiostegium goodwinensis, Leiostegium proprium

Type specimen: USNM 160846, a pygidium

Ecology: nektobenthic carnivore