Diagnosis
Not available.
Genera
This taxon was originally subdivided into numerous genera by Claus, but Müller considered Claus's genera to be too similar, so ascribed all the species to one genus, Conchoecia , but created various groups of similar species. Subsequently, most authors retained the single large genus, until a few years ago when the fashion changed. Now many authorities have re-adopted Claus's genera and created some new ones. However, some of these genera (and groups) are obviously heterogeneous, so the whole taxon has been treated here as a single genus containing 114 known species of which 49 occur in UK waters. In the key that follows, whenever possible, the groups are separated out first.
In the synonomy section the alternative generic names are given, but until a full treatment and diagnosis is given and type species are nominated for all these genera it has been deemed preferable to keep to considering Conchoecia as a single large genus for the purposes of identification.