äyriäisissä

Äyriäiset are a large and diverse group of arthropods belonging to the subphylum Crustacea. They are found in virtually every aquatic environment, from the deep sea to freshwater lakes and rivers, and some terrestrial species also exist. Their bodies are typically segmented and covered by a hard exoskeleton, which they periodically shed as they grow. This exoskeleton provides protection and support.

A defining characteristic of many äyriäisissä is their two pairs of antennae, which are used for sensing their surroundings. They also possess multiple pairs of legs, which can be adapted for walking, swimming, or grasping. Respiration in aquatic äyriäisissä usually occurs through gills, while terrestrial forms may have modified gill structures or lung-like organs.

The diet of äyriäisissä varies greatly depending on the species. Many are scavengers or detritivores, feeding on dead organic matter. Others are predators, hunting smaller invertebrates or fish, while some are filter feeders. Äyriäisissä play a crucial role in aquatic ecosystems, serving as both prey for larger animals and as important decomposers. Economically, many species are harvested for human consumption, including shrimp, crabs, lobsters, and crayfish.