Poecilurus is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of birds in the Furnariidae (ovenbird) family from South America. Today all major authorities include them in Synallaxis

Synallaxis

Synallaxis is a genus of passerine birds in the ovenbird family. They are a member of the spinetails and thistletails, a group of 2 large and some 10 small or monotypic genera.-List of species:*Rufous-capped Spinetail, Synallaxis ruficapilla...

instead, but unlike the "traditional" members of that genus, Poecilurus have closely webbed, broad-tipped, and soft tail feathers. Despite this difference, genetic

Genetics

Genetics , a discipline of biology, is the science of genes, heredity, and variation in living organisms....

evidence supports maintaining them in Synallaxis.