Bivalvia (/ b aɪ ˈ v æ l v i ə /) or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class of aquatic molluscs (marine and freshwater) that have laterally …

双壳纲 [註 1] （學名： Bivalvia ），又名斧足綱（ Pelecypoda ）或瓣鰓綱（ Lamellibranchiata ），俗稱兩扇貝，是软体动物门的一个纲，生于海洋及淡水地区因有两片对称开合的拱形外骨 …

瓣鳃纲（Lamellibranchia ）是指软体动物门的一个纲，属软体动物门，也称作双壳纲（Bivalvia ）或无头纲（Acephala ）。 瓣鳃纲动物全部生活在水中，大部分海产，少数生活在淡水中。

bivalve, (class Bivalvia), any of more than 15,000 species of clams, oysters, mussels, scallops, and other members of the phylum Mollusca characterized by a shell that is divided from front …

Bivalves (also known as “pelecypods” or, in older literature, “lamellibranchs”) are a very diverse and abundant group of mollusks. They live today throughout the world’s oceans and fresh …

bivalve, Any member of the mollusk class Bivalvia, or Pelecypoda, characterized by having a two-halved (valved) shell. Clams, cockles, mussels, oysters, scallops, and shipworms are bivalves. …

There are no known bivalve fossils between the Middle Cambrian and the Early Ordovician, when there was a major increase in body size and an explosion of forms into a variety of habits, …

Jan 26, 2001 · Bivalvia Also known as pelecypods, the approximately 15,000 species of this taxon are found in marine and freshwater habitats throughout the world. A bivalve is characterized …

Bivalves (Figure 7) are laterally compressed molluscs with a hinged, two-part shell. A noncalcified ligament serves as a hinge and connects the two valves along their dorsal surfaces and acts …

双壳纲（Bivalvia）通称贝类。两侧对称，身体侧扁，都具有两枚发达的贝壳包围整个身体，故名双壳纲。壳具有很好的保护作用。头部不明显，只保留有口，口内亦无口腔及齿舌。