Sylviidae is a family of passerine birds that was part of an assemblage known as the Old World warblers. The family was a wastebin taxon with over 400 species of bird in over 70 genera. The family was poorly defined with many characteristics shared with other families. Advances in classification, particularly helped with molecular data, have led to the splitting out of several new families from within this group. Today the smaller family Sylviidae includes the typical warblers in the genus Sylvia, the parrotbills of Asia (formerly a separate family Paradoxornithidae), a number of babblers formerly placed within the family Timaliidae (which is being split) and the wrentit, an unusual North American bird that has been a longstanding taxonomic mystery.