They are divided into two main groups: Inarticulates (no hinges, simple muscle systems) and Articulates (hinged with a complex system).
Unlike bivalves (clams), where shells are mirror images of each other, brachiopod shells are top/bottom oriented and distinct, but each individual valve is symmetrical down the middle. brachiopod
Here is a review of their significance, biology, and fossil record. 🌟 Key Takeaways They are divided into two main groups: Inarticulates
They use a specialized organ called a lophophore , a coil-shaped tentacle structure, to trap food, rather than gills. a coil-shaped tentacle structure
They are benthic (sea-floor dwellers) and sessile (permanently attached to the seafloor), generally filter-feeding.