Colonies of the rugose corals Nemistium liardense sp. nov. and Heritschioides simplex sp. nov. were collected from limestone in the upper member of the Mattson Formation in the Liard Range in the Northwest Territories and are the only known identifiable coral species from the Mattson Fm. The Mattson Fm., deposited in the Liard Basin west of the syndepositional Bovie reverse fault, comprises sandstone with subordinate shale and carbonates deposited during several delta cycles. The close morphological similarity and identical mode of offsetting in N. liardense colonies from the Mattson Fm. and the allochthonous Stikine Terrane of British Columbia indicate they belong in the same species. This and the morphological similarity between H. simplex and the late Serpukhovian to early Bashkirian H. columbicum allow assignment of the coral-bearing part of the upper Mattson Fm. to Bashkirian Foraminiferal Biozone 20. Widespread occurrence of the genus Nemistium confirms open communication between the Liard Basin region and the western European and northern African seas.
Archaeorthoptera is a high rank insect taxon comprising Orthoptera as well as the extinct orders Titanoptera and Caloneurodea, and several other late Paleozoic groups formerly assigned to polyphyletic Protorthoptera. Synapomorphies defining Archaeorthoptera and some fossil subordinate taxa are exclusively based on wing venation. This study presents a detailed description of two new archaeorthopteran genera and three new species from the Pennsylvanian of the Upper Silesian Coal Basin in Poland. These new taxa provide new insights into the wing venation disparity of this remarkable and insufficiently studied insect group. Omaliella polonica sp. nov. is based on a well preserved forewing, including the wing base, which allows a thorough discussion and comparison with other archaeorthopterans. Surprisingly, it is the first complete wing for this group of related genera (Omaliella, Omalia, Coselia and Paleomastax). Owadpteron dareki gen. et sp. nov. has an unusual arrangement of cubital veins. The marked resemblance of the venation of Owadpteron to that of some members of the gerarid line, such as Nacekomia, supports its placement within the family Geraridae (stemgroup Orthoptera). Finally, the venation of Parapalaeomastax dariuszi gen. et sp. nov. strikingly resembles that of the genus Palaeomastax, differing only in the distally branched media. Discovery of these three new archaeorthopterans from the Upper Silesian Coal Basin fits well with that of closely related taxa known from other deposits in Euramerica, such as Mazon Creek Lagerstätte, Avion in Pas-de-Calais Basin and others. Furthermore, a new re-examination of the earliest archaeorthopteran from the Upper Silesian Coal Basin confirms doubtful assignment of this fragmentary fossil to Archaeorthoptera or even to Pterygota.
The anterior part of a medium-sized shark surrounded by hundreds of ostracod shells was found at the end of the last century in a dark limestone nodule from the Kinderscoutian (Bashkirian, Pennsylvanian) near Carsington, Derbyshire (England, UK). The shark is a caseodontoid eugeneodontiform, most probably belonging to Campodus agassizianus. Its dentition is of the crushing type, highly heterodont, but the symphyseal tooth whorl, typical of the most of eugeneodontiforms, was not found. The teeth are symmetrical labio-lingually which is unique in this group. The analysis of the available data leads to the conclusion that neither the tooth whorls of “Campodus variabilis” sensu Eastman, nor the mandibular dentition of “Agassizodus variabilis” sensu St. John and Worthen represent the genus Campodus and that these specimens deserve a new, probably common, name.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.