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Holcorpidae is a small family of extinct insects in the scorpionfly order Mecoptera, which contains a single genus, ''Holcorpa''. Two Eocene age species found in Western North America were placed into the genus, ''H. dillhoffi'' and ''H. maculosa''. ==History and classification== When first described ''Holcorpa'' was identified from a single fossil which is preserved as a compression fossil in fine shales of the Florissant Formation. At the time of description, the Florissant formation was considered to be Oligocene in age. Further refinement of the formation's age using radiometric dating of sanidine crystals has resulted in an age of 34 million years old, which places the formation in the Eocene Chadronian stage. Adjustment to the stages of the Eocene placed the formation in the Priabonian as of 2010.〔 The second species is known from a single fossil that was discovered in silty medium brown Kamloops group shale in the McAbee Fossil Beds near Cache Creek, British Columbia. The McAbee Fossil Beds have been dated in 1981 to the early Eocene Ypresian stage.〔 The genus and type species were first described, without illustration, by Samuel Scudder in 1878,〔 who placed the genus in the family Panorpidae. A second fossil was recovered by a collector in 1907 and first illustrated in 1927 by Theodore Cockerell. The second fossil was finally described in 1931 by Frank M. Carpenter. The second species ''H. dillhoffi'' was described over 130 years after the type species was described. The second species was first described by paleoentomologist S. Bruce Archibald of Simon Fraser University. His type description was published in the entomology journal ''Annales de la Société Entomologique de France''.〔 The specific epithet ''dillhoffi'' is a patronym honoring Richard Dillhoff, who found and donated a number of fossils for research, including the type specimen, and for his support of paleoentomology.〔 The family name Holcorpidae was first used in a 1970 footnote by Russian paleoentomologist Vladimir Zherikhin, who noted the family to be monotypic with only ''Holcorpa''. However since Zherikhin did not provide a detailed subscription for the family itself, the name was considered nomen nudum. The family received a full technical description 19 years later by the German entomologist Rainer Willmann and the circumscription was emended by Archibald in 2010 to reflect the second species.〔 Two genera, ''Fortiholcorpa'' and ''Miriholcorpa'', from the Jurassic Jiulongshan Formation in China were described in 2013. While both are very similar in overall appearance to ''Holcorpa'', both were left unplaced as to family in Mecoptera by the describing authors. ''Fortiholcorpa'' has medial wing veins notably different than those of ''Holcorpa'' and an 8th abdominal segment only slightly longer than the 7th. Conversely, ''Miriholcorpa'' was not placed due to the hind wings not having discernible forking of the median vein into 5 branches. Since the uncertainty is due to the preservation of the only known fossil, Wang ''et al'' noted the placement may change with the discovery of more fossils.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Holcorpa」の詳細全文を読む スポンサード リンク
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