kahekihtilised

Kahekihtilised, also known as 'two-shelled mollusks', refers to a large class of marine and freshwater mollusks that are characterized by a shell composed of two hinged parts. This class, Bivalvia, is one of the largest and most diverse groups within the phylum Mollusca. The two shells, or valves, are typically joined by an elastic ligament, and in many species, a series of interlocking teeth. Muscles attached to the inside of the shells allow the animal to open and close them.

The anatomy of a kahekihtiline is adapted for a sedentary or slow-moving lifestyle. They possess a hatchet-shaped foot, which can be used for burrowing or anchoring. Their feeding mechanism involves filtering food particles from the water using a pair of feathery gills. These gills are also responsible for respiration. Most kahekihtilised are filter feeders, drawing water into their mantle cavity and sifting out microscopic organisms and organic debris.

This group includes well-known animals such as oysters, mussels, clams, and scallops. They inhabit a vast range of aquatic environments, from shallow coastal waters and intertidal zones to deep-sea trenches and freshwater lakes and rivers. Their ecological roles are significant, often serving as important components of food webs and playing a crucial part in water filtration. Many species are also of economic importance, harvested for food or cultivated for pearls.