''Praepapilio'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

of swallowtail butterfly from the middle

Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ...

deposits of

Colorado Colorado (, other variants) is a state in the Mountain states, Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the wes ...

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...

, comparable to the

Lutetian The Lutetian is, in the geologic timescale, a stage or age in the Eocene. It spans the time between . The Lutetian is preceded by the Ypresian and is followed by the Bartonian. Together with the Bartonian it is sometimes referred to as the ...

epoch in age. The genus is considered to be the only representative of the fossil subfamily Praepapilioninae. ''Praepapilio'' is, so far, the only wholly extinct subtaxon known within the swallowtail family. Two species have been described, each from a single fossil find.

Species

''P. colorado''

The holotype of ''P. colorado'', the type species of the genus, is from the Middle Eocene-aged Green River Shale, Parachute Creek Member, near Raydome,

. Durden and Rose, in their 1978 paper, compare ''P. colorado'' to the extant ''

Baronia brevicornis ''Baronia brevicornis'', commonly known as the short-horned baronia, is a species of butterfly in the monotypic genus ''Baronia'' and is placed in a subfamily of its own, the Baroniinae, a sister group of the remainder of the swallowtail butterf ...

'', and suggest that ''P. gracilis'' may be the same species as ''P. colorado'', and that the differences between the two are possibly due to

sexual dimorphism Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most an ...

''P. gracilis''

As with ''P. colorado'', the holotype of ''P. gracilis'' was from the same site in Colorado. It differs from the type species in being smaller and more gracile in form, though anatomical differences may be due to sexual dimorphism.

References

† Fossil Lepidoptera Eocene insects Prehistoric insects of North America † {{paleo-Lepidoptera-stub