sentences:  There are no exact statistics covering all animal groups.In 2,200 names of species and 350 names of genera in European non-marine molluscs, which might be a representative group of animals, 0.7% of the specific and 3.4% of the generic names were correctly established as new replacement names (and a further 0.7% of the specific and 1.7% of the generic names have incorrectly been regarded as new replacement names by some authors).For those taxa whose names are regulated by the International Code of Nomenclature for algae, fungi, and plants (ICNafp), a nomen novum or replacement name is a name published as a substitute for "a legitimate or illegitimate, previously published name, which is its replaced synonym and which, when legitimate, does not provide the final epithet, name, or stem of the replacement name".