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
Little shearwater a clutch of one clear white egg, measuring around . The egg is incubated for 52 to 58 days by both sexes. Little shearwater The little shearwater ("Puffinus assimilis") is a small shearwater in the petrel family Procellariidae. Despite the generic name, it is unrelated to the puffins, which are auks, the only similarity being that they are both burrow-nesting seabirds. This shearwater has the typically "shearing" flight of the genus, dipping from side to side on stiff wings with few beats, the wingtips almost touching the water, though in light winds it has a more flapping flight than that