Puffinus be divided in what has been called the "Puffinus" and the "Neonectris" group after notable species; the latter has been separated as a distinct genus named "Ardenna". The former is taxonomically confusing, with species having been split and remerged in the last years. The genus "Puffinus" contains the following species: Several fossil species which became extinct long ago are also known. The proportion of larger ("Neonectris") species apparently was larger before the Pliocene, i.e. before marine mammals diversified: ""Puffinus" arvernensis" (Early Miocene of France) is now considered a primitive albatross of the fossil genus "Plotornis". Puffinus Puffinus is a genus
Bulweria "b" sequence analysis has proven them to be closely related to the shearwaters in the genus "Puffinus" and especially the "Procellaria" petrels. Bulweria Bulweria is a genus of seabirds in the family Procellariidae named after English naturalist James Bulwer. The genus has two extant species, Bulwer's petrel ("B. bulwerii") and Jouanin's petrel ("B. fallax"). A third species, the Olson's petrel ("Bulweria bifax"), became extinct in the early 16th century; it is known only from skeletal remains. Bulwer's Petrel ranges in the Atlantic, Indian and Pacific Oceans, whereas Joaunin's Petrel is confined to the northwestern Indian Ocean. Olson's Petrel is known