Trilobites of the suborder Illaenina from the Silurian of north Queensland, Australia

摘要: The trilobite fauna of the middle Silurian (Telychian to possibly earliest Sheinwoodian) Tomcat Creek limestone in Broken River Province north Queensland is dominated by suborder Illaenina, including illaenimorphs (Illaeninae and Bumastinae) members Scutelluidae. Scutelluidae are most diverse, with eight genera, which Dolabrapex, Iotoryx, Perizostra, Quintonia new. Perizostra first scutelluid a cephalon that may be described as phacomorph appearance. Illaenimorphs represented three Opsypharus, regarded senior synonym Paracybantyx but distinct from Failleana it has been placed synonymy some authors. Thirteen species new: Cybantyx? ergodes, Opsypharus pandanensis, Australoscutellum talenti, Dolabrapex acomus, Illaenoscutellum psephos, Iotoryx clarksoni, Japonoscutellum mawsonae, J. drakton, fractum, Kosovopeltis avita, campbelli, arata, Q. pavo. A Stenoparia open nomenclature. Australoscutellum, Illaenoscutellum, oldest known representatives those genera. These genera also common faunas limestones Wenlock Ludlow age central western New South Wales, reflecting similarity lithofacies. monotypic Late Ordovician genus Craigheadia, scutelluid, belongs Lichidae probably junior Leiolichas.