conchostraca

Conchostraca, commonly known as clam shrimp or superficially as seed shrimp due to their resemblance to seeds, are a superorder of crustaceans belonging to the subclass Phyllopoda. They are aquatic crustaceans that typically inhabit freshwater environments, though some species can be found in brackish water. Conchostracans are characterized by their bivalve carapace, which encloses their entire body, giving them a superficial resemblance to small clams or mussels. This carapace is typically thin and translucent, and is shed and regrown multiple times during their life cycle.

Conchostracans possess numerous pairs of leaf-like appendages (phyllopods) that they use for both locomotion and filter-feeding. They are detritivores, feeding on organic matter suspended in the water column or settled on the substrate. Their life cycle often involves the production of resting eggs, also known as ephippia, which are resistant to desiccation and can survive for extended periods in dry mud. These eggs hatch when rehydrated, allowing conchostracans to recolonize ephemeral water bodies. Their distribution is global, and they play a role in freshwater ecosystems as a food source for fish and other aquatic organisms. Despite their widespread presence, they are often overlooked due to their small size and cryptic lifestyle.