Nerve net Nerve net A nerve net consists of interconnected neurons lacking a brain or any form of cephalization. While organisms with bilateral body symmetry are normally associated with a central nervous system, organisms with radial symmetry are associated with nerve nets. Nerve nets can be found in members of the Cnidaria, Ctenophora, and Echinodermata phyla, all of which are found in marine environments. Nerve nets can provide animals with the ability to sense objects through the use of the sensory neurons within the nerve net. The nerve net is the simplest form of a nervous system found in multicellular organisms. Unlike
Bacterial phyla similarity with the other Deferribacteres ("Deferribacter" species and relatives) and is considered a separate phylum by Rappé and Giovannoni. Additionally the placement of the genus "Geovibrio" in the phylum Deferribacteres is debated. With the advent of methods to analyse environmental DNA (metagenomics), the 16S rRNA of an extremely large number of undiscovered species have been found, showing that there are several whole phyla which have no known cultivable representative and that some phyla lack in culture major subdivisions as is the case for Verrucomicrobia and Chloroflexi. The term Candidatus is used for proposed species for which the lack of information