Scellus Explained

Scellus is a genus of flies in the family Dolichopodidae.^[1] It is distributed in the Palearctic and Nearctic.

Males of the genus have a pair of flag-like appendages, known as "signa" (singular "signum"), that emanate laterally from between the 4th and 5th abdominal segments. These appendages are connected together by a band under the sternites, forming a U-shaped structure called the "cingulum". It has been suggested by researchers that these appendages are used for visual signalling or pheromone dispersal during courtship. The genus Hydatostega also has a cingulum, but much reduced, suggesting that Scellus and Hydatostega are closely related.^{[2] [3]}

Species

• Scellus abditus Hurley, 1995^[4]
• Scellus alactaga Stackelberg, 1951^[5]
• Scellus amplus Curran, 1923^[6]
• Scellus asaroticus Hurley, 1995^[4]
• Scellus avidus Loew, 1864^[7]
• Scellus bianchii Stackelberg, 1951^[5]
• Scellus coloradensis Harmston & James in Harmston & Knowlton, 1942
• Scellus crinipes Van Duzee, 1925^[8]
• Scellus dolichocerus Gerstaecker, 1864^[9]
• Scellus dyscritus Hurley, 1995^[4]
• Scellus exustus (Walker, 1852)
• Scellus filifer Loew, 1864^[7]
• Scellus gallicanus Becker, 1909^[10]
• Scellus grichanovi Naglis, 2012^[11]
• Scellus hissaricus Stackelberg, 1951^[5]
• Scellus knowltoni Harmston, 1939^[12]
• Scellus monstrosus Osten Sacken, 1877^[13]
• Scellus notatus (Fabricius, 1781)
• Scellus obuchovae (Stackelberg, 1951)^[5]
• Scellus paramonovi Stackelberg, 1926
• Scellus sinensis Yang, 1998^[14]
• Scellus spinimanus (Zetterstedt, 1843)
• Scellus tshernovskii Stackelberg, 1951^[5]
• Scellus varipennis Van Duzee, 1925^[8]
• Scellus vigil Osten Sacken, 1877^[13]
• Scellus virago Aldrich, 1907^[15]

Notes and References

1. Book: Yang. D.. Zhu. Y.. Wang. M.. Zhang. L.. World Catalog of Dolichopodidae (Insecta: Diptera).. 2006. China Agricultural University Press. Beijing. 9787811171020. 1–704.
2. Runyon. Justin. 2008. The cingulum: A unique structure of some Dolichopodidae. Fly Times. 41. 3.
3. Web site: Curated Scellus virago specimen from the CAS - Scellus virago - ♂. Schusteff. Aaron. 16 December 2015. BugGuide. 30 December 2023.
4. Book: Hurley. R. L.. Griffiths. C.D.C.. Orthogenya Dolichopodidae. Hydrophorinae. in Flies of Nearctic Region. 1995. E. Schweizerbartsche Verlagsbuchhandlung. Stuttgart. 6. 6. 1. 978-3-510-70021-9. 113–224.
5. Stackelberg. A.. Palaearctic species of the genus Scellus lw (Diptera Dolichopodidae). Entomologicheskoe Obozrenie. 1951. 31. 595–608.
6. Curran. C. H.. An apparently undescribed species of Scellus (Dolichopodidae, Diptera). Canadian Entomologist. 1923. 55. 73–74. 10.4039/ent5573-3.
7. Loew. H.. Monographs of the Diptera of North America. Smithson. Misc. Collect.. 1864. 6. Part II.
8. Van Duzee. M. C. Scellus virago Aldrich (a two-winged fly) and two forms closely related to it. Proceedings of the California Academy of Sciences. 14. 10. 175–183 . 4th series . 16 July 2016.
9. Gerstaecker. A.. Uebersicht der in der Umgegend Berlins bis jetzt beobachteten Dolichopoden. Entomologischer Verein zu Stettin. 1864. 25. 20–48 . de.
10. Becker. T.. Dipteren der Kanarischen Inseln. Mitteilungen aus dem zoologischen Museum in Berlin. 1908. 4. 5 October 2015. Berlin . de.
11. Naglis. S.. 2012. New records of Hydrophorinae (Diptera, Dolichopodidae) from Turkey, with the description of a new species of Scellus Loew. Mitteilungen der Schweizerischen Entomologischen Gesellschaft. 85. 1–2. 45–49. 10.5169/seals-403038. free.
12. Harmston. F. C.. A new Scellus Dolichopodidae Diptera with key to males. Proceedings of the Utah Academy of Sciences. 1939. 16. 71–73.
13. Osten Sacken. Karl Robert. Western Diptera: Descriptions of new genera and species of Diptera from the region west of the Mississippi and especially from California.. [U.S. Department of the Interior] Bulletin of the United States Geological and Geographical Survey of the Territories. 1877. 3. 189–354. 10 July 2016.
14. Yang. D.. New and little known species of Dolichopodidae (Diptera) from China (II). Bulletin de l'Institut royal des sciences naturelles de Belgique. Entomologie. 1998. 68. 165–176.
15. Aldrich. J. M.. The dipterous genus Scellus, with one new species. Entomological News Philadelphia. 1907. 19. 133–136. 16 July 2016.