Bioerosion describes the breakdown of hard ocean substrates – and less often terrestrial substrates – by living organisms. Marine bioerosion can be caused by mollusks, polychaete worms, phoronids, sponges, crustaceans, echinoids, and fish; it can occur on coastlines, on coral reefs, and on ships; its mechanisms include biotic boring, drilling, rasping, and scraping. On dry land, bioerosion is typically performed by pioneer plants or plant-like organisms such as lichen, and mostly chemical or mechanical in nature.
The Rostroconchia is a class of extinct molluscs dating from the early Cambrian to the Late Permian. They were initially thought to be bivalves, but were later given their own class. They have a single shell in their larval stage, and the adult typically has a single, pseudo-bivalved shell enclosing the mantle and muscular foot. The anterior part of the shell probably pointed downward and had a gap from which the foot could probably emerge. Rostroconchs probably lived a sedentary semi-infaunal lifestyle. There were probably more than 1,000 species of members of this class.
Praenuculidae is an extinct family of prehistoric bivalves in the superfamily Nuculoidea. Praenuculidae species lived from the early Ordovician, Arenig stage through the Early Devonian Emsian stage. Praenuculidae fossils are found worldwide, present on every continent except Antarctica. Species in this family are thought to have been sessile, attached to the substrate in shallow infaunal marine water environments, where they formed shells of an aragonite composition. The family Praenuculidae was named by A. Lee McAlester in 1969.
Nanahughmilleria is a genus of eurypterid, an extinct group of aquatic arthropods. Fossils of Nanahughmilleria have been discovered in deposits of Devonian and Silurian age in the United States, Norway, Russia, England and Scotland, and have been referred to several different species.
Atrypa is a genus of brachiopod with round to short egg-shaped shells covered with many fine radial ridges. Growth lines form perpendicular to the costae and are spaced approximately 2 to 3 times further apart than the costae.. The pedunculate valve is slightly convex, but oftentimes levels out or becomes slightly concave toward the anterior margin. The brachial valve is highly convex. Neither valve contains an interarea. Atrypa had a large geographic range 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.
Plumulites is an extinct genus of machaeridians, extinct annelid group.
Pojetaia is an extinct genus of early bivalves, one of two genera in the extinct family Fordillidae. The genus is known solely from Early to Middle Cambrian fossils found in North America, Greenland, Europe, North Africa, Asia, and Australia. The genus currently contains two accepted species, Pojetaia runnegari, the type species, and Pojetaia sarhroensis, though up to seven species have been proposed. The genera Buluniella, Jellia, and Oryzoconcha are all considered synonyms of Pojetaia.
Concavodonta is an extinct genus of early bivalve in the extinct family Praenuculidae. The genus is one of three genera in the subfamily Concavodontinae. Concavodonta is known solely from late Ordovician, Caradoc epoch, fossils found in Europe and South America. The genus currently contains three accepted species, Concavodonta imbricata, Concavodonta ovalis and the type species Concavodonta ponderata.
Hemiconcavodonta is an extinct genus of bivalve in the extinct family Praenuculidae. The genus is one of three genera in the subfamily Concavodontinae. Hemiconcavodonta is known solely from late Ordovician, Caradoc epoch, fossils found in South America. The genus currently contains a single accepted species, Hemiconcavodonta minuta.
Concavodontinae is an extinct subfamily of prehistoric bivalves in the family Praenuculidae. Concavodontinae species lived from the middle Ordovician, Caradoc epoch through the late Ordovician Ashgill epoch. Concavodontinae fossils are found in Europe and South America, and species are thought to have been stationary attached to substrate in shallow infaunal marine water environments where they formed shells of an aragonite composition. The subfamily Concavodontinae was named by Teresa M. Sánchez in 1999.
Emiliodonta is an extinct genus of bivalve in the extinct family Praenuculidae. The genus is one of three genera in the subfamily Concavodontinae. Emiliodonta is known solely from late Ordovician, Caradocian epoch, fossils found in South America. The genus contains a single accepted species, Emiliodonta cuerdai.
Praenuculinae is an extinct subfamily of prehistoric bivalves in the family Praenuculidae. Praenuculinae species lived from the middle Ordovician through the late Devonian. Praenuculinae fossils are found in Europe, Africa, North America and South America, and species are thought to have been stationary attached to substrate in shallow infaunal marine water environments where they formed shells of an aragonite composition. The subfamily Praenuculinae was named by Teresa M. Sánchez in 1999.
Cuyopsis is an extinct genus of bivalve in the extinct family Praenuculidae. The genus is one of eleven genera in the subfamily Praenuculinae. It is one of three Praenuculinae genera known solely from late Ordivician, Caradoc epoch, fossils found in South America. Cuyopsis currently contains a single accepted species, Cuyopsis symmetricus.
Villicumia is an extinct genus of bivalve in the extinct family Praenuculidae. The genus is one of eleven genera in the subfamily Praenuculinae. It is one of three Praenuculinae genera known solely from late Ordovician, Caradoc epoch, fossils found in South America. Villicumia currently contains a single accepted species, Villicumia canteraensis.
Trigonoconcha is an extinct genus of bivalve in the extinct family Praenuculidae. The genus is one of eleven genera in the subfamily Praenuculinae. It is one of three Praenuculinae genera known solely from Late Ordivician, Caradoc epoch, fossils found in South America. Trigonoconcha currently contains a single accepted species, Trigonoconcha acuta.
Panenka is a genus of fossil saltwater clams, marine bivalve molluscs in the family Praecardiidae. Like most bivalves, these molluscs were suspension feeders. They lived in the Devonian Period.
A hinge ligament is a crucial part of the anatomical structure of a bivalve shell, i.e. the shell of a bivalve mollusk. The shell of a bivalve has two valves and these are joined by the ligament at the dorsal edge of the shell. The ligament is made of a strong, flexible and elastic, fibrous, proteinaceous material which is usually pale brown, dark brown or black in color.
Trimerellida is an extinct order of craniate brachiopods, containing the sole superfamily Trimerelloidea and the families Adensuidae, Trimerellidae, and Ussuniidae. Trimerellidae was a widespread family of warm-water brachiopods ranging from the Middle Ordovician to the late Silurian (Ludlow). Adensuidae and Ussuniidae are monogeneric families restricted to the Ordovician of Kazakhstan. Most individuals were free-living, though some clustered into large congregations similar to modern oyster reefs.
Thracia pubescens is a bivalve mollusc in the family Thraciidae.
Wiedopterus is a genus of eurypterid, an extinct group of aquatic arthropods. The type and only species of Wiedopterus, W. noctua, is known from deposits of Early Devonian age in Germany. The generic name derives from the Wied river, which runs near the site of the initial discovery, and the species name, noctua, derives from Latin noctua (owl) which refers to the superficial resemblance of the carapace to an owl.
