 They can even have the same epithet, distinguished by typography (see botanical name for explanation of epithets), although since January 2010 it is not permitted to publish such grex names if the nothospecies name already exists.Hybrids between a grex and a species/nothospecies are named as greges, but this is not permitted if the nothospecies parent has the same parentage as the grex parent.That situation is a back-cross, and the nothospecies name is applied to the progeny.