Trigoniids

Trigoniids are a group of extinct marine bivalve mollusks that lived during the Mesozoic era, from the Triassic to the Cretaceous periods. They are characterized by their triangular or trigonal shell shape, which gives them their name. Trigoniids are known for their diverse range of forms and sizes, with some species reaching up to 30 centimeters in length. They were widespread in marine environments, from shallow coastal areas to deep-sea settings. The shells of trigoniids are typically inequivalved, meaning the two valves are not mirror images of each other, and they often exhibit a variety of ornamentation patterns. Trigoniids played an important role in their ecosystems, serving as both prey and habitat for other marine organisms. Their fossils are commonly found in sedimentary rocks, providing valuable insights into the paleoenvironments and paleobiology of the Mesozoic era. The study of trigoniids is an active area of research in paleontology, as they offer clues about the evolution of marine life and the changes in oceanic conditions over millions of years.