The nervous system (NS) of invertebrates and vertebrates is composed of two main types of
cells: neurons and glia. In both types of organisms, nerve cells have similarities in …

Polychaetes inhabit a wide variety of habitats and show a great morphological diversity. In
this context, a key morphological structure for adapting to their individual lifestyles and …

Nuchal organs are epidermal sensory structures present in most annelids. Based on one of
the interpretations, they serve in larval settlement. Siboglinids lack nuchal organs in adult …

The general morphology of the body, including the distribution of putative sensory ciliary
cells, was studied using scanning electron microscopy (SEM) in the siboglinid Nereilinum …

Abstract Background Head appendages in Annelida contribute significantly to the immense
morphological diversity in this spiralian taxon. Nevertheless, the evolutionary origin of …

Background The nervous system of siboglinids has been studied mainly in Osedax and
some Vestimentifera, while data in Frenulata–one of the four pogonophoran main branches …

Annelida can be found in all kind of habitats and thus show a huge diversity in form, size,
and colour. A key structure for their evolutionary success and adaptability to their individual …