''Protostephanus'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus of

crown wasp The Stephanidae, sometimes called crown wasps, are a family of parasitoid wasps. They are the only living members of the superfamily Stephanoidea. Stephanidae has at least 345 living species in 11 genera. The family is considered cosmopolitan in ...

in the

Hymenoptera Hymenoptera is a large order (biology), order of insects, comprising the sawfly, sawflies, wasps, bees, and ants. Over 150,000 living species of Hymenoptera have been described, in addition to over 2,000 extinct ones. Many of the species are Par ...

family

Stephanidae The Stephanidae, sometimes called crown wasps, are a family of parasitoid wasps. They are the only living members of the superfamily Stephanoidea. Stephanidae has at least 345 living species in 11 genera. The family is considered cosmopolitan in ...

known from an Eocene fossil found in the United States of America. The genus contains a single described species, ''Protostephanus ashmeadi'' placed in the stephanid subfamily Stephaninae.

History and classification

''Protostephanus'' is known only from a single fossil, the holotype, specimen number "2035" and formerly number 13913 of the

Samuel Hubbard Scudder Samuel Hubbard Scudder (April 13, 1837 – May 17, 1911) was an American entomologist and paleontologist. He was a leading figure in entomology during his lifetime and the founder of insect paleontology in America. In addition to fossil insects, ...

collection. The specimen is housed in the fossil collection of the Museum of Comparative Zoology, part of Harvard University. The specimen is composed of a partially complete adult female crown wasp that has been preserved as a compression fossil in shale of fine volcanic ash from the Florissant Formation in Colorado. When the fossil was first recovered and studied, the age of the Florissant Formation was not firmly determined, and a tentative Miocene date was advocated. The formation has subsequently been determined to be late Eocene in age. The ''Protostephanus'' fossil was first studied by paleoentomologist Theodore Dru Alison Cockerell of the Museum of Comparative Zoology. Cockerell's 1906

type description A species description is a formal description of a newly discovered species, usually in the form of a scientific paper. Its purpose is to give a clear description of a new species of organism and explain how it differs from species that have be ...

of the new genus and species was published in the journal ''Bulletin of the Museum of Comparative Zoology at Harvard College''. The genus name ''Protostephanus'' was coined by Cockerell as a combination of the Greek word ''proto'' meaning "first" and the stephanid genus '' Stephanus''. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

''ashmeadi'' was coined in honor of William Harris Ashmead whose entomology works were referenced by Cockerell to determine the affinities of the insect. ''Protostephanus'' is the first crown wasp genus to have been described from a fossil, and is the youngest fossil genus in the family. Cockerell was uncertain of his placement for the ''Protostephanus'' as a crown wasp, not being able to see all the features typical of the family. This uncertainty remained until the holotype was reexamined by Alexandre Aguiar and Jens-Wilhelm Janzen in 1999. Aguiar and Janzen concluded that the placement was sound with most of the expected features being present partly or fully. The incomplete nature of the specimen lead to the genus being left unplaced in the subfamily Stephaninae when it was subdivided into tribes.

Description

The ''Protostephanus'' adult is preserved in a side view, with an overall length of . As with all crown wasps, a series of projections surrounding the middle ocellus, forming a "crown" head are present. The side and rear projections are clearly preserved in the ''Protostephanus'' holotype. The

hyaline A hyaline substance is one with a glassy appearance. The word is derived from el, ὑάλινος, translit=hyálinos, lit=transparent, and el, ὕαλος, translit=hýalos, lit=crystal, glass, label=none. Histopathology Hyaline cartilage is ...

(translucent) fore-wings have an overall length of with veins that show a preserved brassy coloration. The wing venation is almost exactly the same as that seen in the modern genera '' Schlettererius'' and ''

Megischus ''Megischus'' is a genus of crown wasp. It was circumscription (taxonomy), circumscribed by Gaspard Auguste Brullé in 1846. The genus has a cosmopolitan distribution, and over eighty species are recognized. It is the type genus of the tribe (bio ...

''. The hind legs show a typical crown wasp structure, having an inflated tibia, and a lengthened tarsus that is divided into three segments. There is no definable male genitalia on the type specimen; rather, there is a probable

ovipositor The ovipositor is a tube-like organ used by some animals, especially insects, for the laying of eggs. In insects, an ovipositor consists of a maximum of three pairs of appendages. The details and morphology of the ovipositor vary, but typical ...

indicating the specimen is female.

References

{{Taxonbar, from=Q7252134 Stephanoidea Prehistoric Hymenoptera genera

† A dagger, obelisk, or obelus is a typographical mark that usually indicates a footnote if an asterisk has already been used. The symbol is also used to indicate death (of people) or extinction (of species). It is one of the modern descendan ...

Eocene insects Fossil taxa described in 1906 Prehistoric insects of North America Florissant Formation