a complex is some sort of an extra taxonomic level, unrecognized officially but very helpful in identification.
one groups taxa at the same rank in a complex and indicates one of the taxa as the representing one.
this is generally done at the rank of species or genus.
when one identifies an accession to the representing taxon of a complex, the question arises whether this identification is sensu stricto (that is, you really mean that taxon) or sensu lato (that is, you really mean the complex the taxon identifies).
a complex is some sort of an extra taxonomic level, unrecognized officially but very helpful in identification. one groups taxa at the same rank in a complex and indicates one of the taxa as the representing one. this is generally done at the rank of species or genus. when one identifies an accession to the representing taxon of a complex, the question arises whether this identification is sensu stricto (that is, you really mean that taxon) or sensu lato (that is, you really mean the complex the taxon identifies).