Worm mollusks
| Worm mollusks | ||||||||||
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Epimenia verrucosa |
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| Systematics | ||||||||||
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| Scientific name | ||||||||||
| Aplacophora | ||||||||||
| from Ihering , 1876 | ||||||||||
| Classes | ||||||||||
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As aplacophora (Aplacophora) a group vermiform and shell-less traditionally molluscs denotes both the class of caudofoveata (Caudofoveata) and the solenogastres comprises (Solenogastres).
Body shape and shell
It is not clear whether the animals of these two classes changed their shell , which is present in all other molluscs, in the course of evolution , or whether they never had one. Instead of a shell, however, their outer skin layer contains aragonite needles or is covered by small aragonite scales. The worm shape of the animals is the result of a reduction in the muscular foot.
system
The worm mollusks are no longer considered to be a monophyletic group . The position of the two classes within the molluscs has not been conclusively established either. Sometimes they were combined with the beetle snails in a Monophylum aculifera (spiny molluscs).
literature
- Klaus-Jürgen Götting: Aplacophora, worm mollusks In: Westheide, Rieger (Hrsg.): Special Zoology Part 1: Protozoa and invertebrates. Gustav Fischer Verlag, Stuttgart, Jena 1997; Pages 285ff.
