Secreting a dwelling tube is a common phenomenon among phoronid, pogonophoran and annelid worms.
Secreted products among the non-pogonophoran annelids range from mucus to calcium carbonate.
With the exception of a few marine sanguinicolids that use annelids, a mollusc is the required first intermediate host for all flukes.
As they note, however, recent molecular evidence suggests this intriguing group may have nothing to do with the annelids, let alone the polychaetes.
Invertebrates collected have included varieties of sponge, anemone, annelid, mollusc, crustacean, asteroid, ophiuroid, echinoid, holothurioid and tunicate.
Palaeoscolecid worms may be nematomorphs rather than annelids.
Another hot topic in the last few years has been the phylogenetic position of the brachiopods, with decisive evidence placing them close to the annelids and molluscs (as lophotrochozoans).
The young toads and the adult toads consume insects, such as flies and beetles, shrimp and larvae; but also annelid worms and terrestrial arthropods.
