WAnticalyptraea is a fossil genus of encrusting tentaculitoid tubeworms from the Silurian to Devonian of Europe and North America . Anticalyptraea commonly encrust various invertebrate fossils such as stromatoporoids, rugose corals, bryozoans, brachiopods and crinoids, but they can also be common on the hardgrounds. They were often attacked by predators in the Pridoli of Baltica.
WAtrypa is a genus of brachiopod with shells round to short egg-shaped, covered with many fine radial ridges, that split further out and growthlines perpendicular to the costae and 2-3 times wider spaced. The pedunculate valve is a little convex, but tends to level out or even become slightly concave toward the anterior margin. The brachial valve is highly convex. There is no interarea in either valve. Atrypa was a cosmopolitan and occurred from the late Lower Silurian (Telychian) to the early Upper Devonian (Frasnian). Other sources expand the range from the Late Ordovician to Carboniferous, approximately from 449 to 336 Ma. A proposed new species, A. harrisi, was found in the trilobite-rich Floresta Formation in Boyacá, Colombia.
WDawsonoceratidae is an extinct family of orthoconic nautiloid cephalopods that lived in what would be North America and Europe from the Late Ordovician through the Middle Devonian from about 480–390 mya, existing for approximately 90 million years.
WLeptaena is an extinct genus of mid-sized brachiopod that existed from the Dariwilian epoch to the Emsian epoch, though some specimens have been found in strata as late in age as the Tournasian epoch. Like some other Strophomenids, Lepteana were epifaunal, meaning they lived on top of the seafloor, not buried within it, and were suspension feeders.
WOrthacanthus is an extinct genus of fresh-water xenacanthid sharks, named by Louis Agassiz in 1836, ranging from the Upper Carboniferous until the Lower Permian. Orthacanthus had a nektobenthic life habitat, with a carnivorous diet. Multiple sources have also discovered evidence of cannibalism in the diet of Orthacanthus and of "filial cannibalism" where adult Orthacanthus preyed upon juvenile Orthacanthus. The genus Orthacanthus has been synonymized with Dittodus, Didymodus, and Diplodus.
WPlatystrophia is an extinct genus of brachiopods that lived from the Ordovician to the Silurian in Asia, Europe, North America, and South America. It has a prominent sulcus and fold. It usually lived in marine lime mud and sands.
WRafinesquina is an extinct genus of large brachiopod that existed from the Darriwilian to the Ludlow epoch.
WSpirifer is a genus of marine brachiopods belonging to the order Spiriferida and family Spiriferidae. Species belonging to the genus lived from the Middle Ordovician (Sandbian) through to the Middle Triassic (Carnian) with a global distribution. They were stationary epifaunal suspension feeders.