Monoplacophora
| Monoplacophora Temporal range: | |
|---|---|
| The holotype of Neopilina galatheae at the Zoological Museum, Copenhagen | |
| Scientific classification | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Subphylum: | Conchifera |
| Class: | Monoplacophora Odhner, 1940 |
Monoplacophora /ˌmɒnoʊpləˈkɒfərə/, meaning "bearing one plate", is a polyphyletic class of molluscs with a cap-like shell, inhabiting deep sea environments. Extant representatives were not recognized as such until 1952; previously they were known only from the fossil record, and were thought to have become extinct 375 million years ago.
Although the shell of many monoplacophorans is limpet-like in shape, they are not gastropods, nor do they have any close relation to gastropods.