Veliger of Scaphopods
The scaphopods, or tusk shells, have a veliger larva very similar to that of bivalves, despite the great difference in the appearance of the adults. The shell develops in a similar way, developing a bi-lobed form that surrounds the larval body. However, unlike bivalves, this never splits into two, and, in fact, fuses along the ventral margin, eventually becoming a tube that encloses the length of the body, and is open at both ends.
The scaphopod veliger is free-living, and metamorphosis is marked by a great elongation of the body, in order to assume the adult form.
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