''Saurophthirus'' is an extinct genus of giant

stem-group In phylogenetics, the crown group or crown assemblage is a collection of species composed of the living representatives of the collection, the most recent common ancestor of the collection, and all descendants of the most recent common ancestor. ...

flea Flea, the common name for the order Siphonaptera, includes 2,500 species of small flightless insects that live as external parasites of mammals and birds. Fleas live by ingesting the blood of their hosts. Adult fleas grow to about long, a ...

, and the only member of the family Saurophthiridae. The type species, ''S. longipes'' is found in early Cretaceous strata of

Baissa The Zaza Formation is a geological formation located in Buryatia (Russia). It dates to the Lower Cretaceous period. It is Aptian in age and consists of sandstones, siltstones, marls and bituminous shales, deposited in a stratified lake. It is s ...

, Siberia. Two other species ''S. exquisitus'' and ''S. laevigatus'' are from the Lower Cretaceous

Yixian Formation The Yixian Formation (; formerly transcribed as Yihsien Formation) is a geological formation in Jinzhou, Liaoning, People's Republic of China, that spans the late Barremian and early Aptian stages of the Early Cretaceous. It is known for its ex ...

of China.Gao, Taiping, et al. "New Transitional Fleas from China Highlighting Diversity of Early Cretaceous Ectoparasitic Insects." Current Biology 23.13 (2013): 1261-1266.

Description

Body length of largest species, ''S. longipes'' is long. They are generally seen as transitional between more primitive stem-fleas such as

Pseudopulicidae Pseudopulicidae is an extinct family of stem-group fleas from the Middle Jurassic to Early Cretaceous of China. They represent the oldest known group of stem-fleas. Like other stem-group "giant fleas", they are much larger and lack the specialised ...

and ''

Tarwinia ''Tarwinia'' is an extinct genus of stem-group flea known from a single species, ''T. australis'', from the Early Cretaceous ( Aptian) Koonwarra Fossil Bed of Victoria Victoria most commonly refers to: * Victoria (Australia), a state of ...

'' and modern fleas.

References

Siphonaptera genera Cretaceous insects Transitional fossils Cretaceous insects of Asia Parasites of reptiles Prehistoric insect genera Fossil taxa described in 1976 {{parasitic animal-stub