Bullidae
| Bulla | |
|---|---|
 |
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| A shell of Bulla quoyii | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Gastropoda |
| (unranked): |
clade Heterobranchia clade Euthyneura clade Euopisthobranchia clade Cephalaspidea |
| Superfamily: |
Bulloidea (Lamarck, 1801) |
| Family: |
Bullidae (Rafinesque, 1815) |
| Genus: |
Bulla Linnaeus, 1758 |
| Type species | |
|
Bulla ampulla Linnaeus, 1758 |
|
| Species | |
|
See text |
|
| Synonyms | |
|
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clade Cephalaspidea
See text
Bulla is a genus of medium to large hermaphrodite sea snails, shelled marine opisthobranch gastropod molluscs. These herbivorous snails are in the suborder Cephalaspidea, headshield slugs, and the order Opisthobranchia.
These snails are popularly known as "bubble snails", and their shells as "bubble shells", because the shell of some of the species is very inflated indeed, almost spherical in shape, and is also very thin and light.
According to some experts, Bulla is currently the only genus in the family Bullidae, which in turn is the only member of the superfamily Bulloidea.
All Bulla species have large, ovate external shells, which are large enough to accommodate the whole snail when retracted. All species have rather similarly shaped shells. The shells have a deep, narrow umbilicus at the apex. There is no operculum.
The smooth shell of Bulla is ovate and expanded, with a deep, sunken involute top. Since there is little difference between the shells and in the morphology of the radular teeth, there is some uncertainty about the exact taxonomy of the species in Bulla.
The gizzard of Bulla is rather different from that of other herbivorous groups. It has three large crushing plates and ancillary corneous spines, instead of just grinding plates. The crawling snails show prominent, frilled or lobed parapodia.
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Wikipedia