S. A. Marshall1
S. A. Marshall1
The subfamilies, genera, and most frequently encountered species of North American Calliphoridae are reviewed, including a comprehensive pictorial key to the forensically important blow flies of North America. Distribution maps are provided for all species.
Lucilia sericata (Photo by S.A. Marshall)
Correct species identification of necrophagous insects is pivotal to their use as evidence in death investigations because many of their attributes are species-specific, including seasonality, distribution, habitat preference and rate of development of larvae in a corpse at particular temperatures. Furthermore, reliable identification of insect species facilitates access to relevant information stored in published literature and allows scientists to communicate and contextualize their findings effectively. Blow flies, because of their abundance, diversity and characteristic roles in the decomposition of carrion, have proven to be of particular importance in forensic entomology.
We here build upon and expand the photographic keys to the northeastern North American Calliphoridae by Marshall et al. (2011), providing keys to the 5 subfamilies and 17 genera of blow flies occurring in North America, and to 41 of the 93 species currently recorded from North America. The species keyed herein include all North American species of possible forensic importance. A map is provided for each of the keyed species. The remaining 51 Nearctic species are mostly parasites or parasitoids, and none are known to develop in carrion. The Nearctic species not included are the 28 species of bird parasites in the genus Protocalliphora Hough, the eight species of Melanodexia Williston, the five species of Angioneura Brauer & Bergenstamm, the four species of Opsodexia Townsend, and the six species of Pollenia Robineau-Desvoidy. Keys to species of Protocalliphora can be found in Sabrosky et al. (1989) and in Whitworth (2002, 2003, and 2006). Keys to Melanodexia are available in Hall (1948), but this infrequently encountered genus needs revision. Keys to the Melanomyinae including Angioneuria and Opsodexia are available in Downs (1986). A separate pictorial key to species of North American Pollenia is available in Jewiss-Gaines, et al. (2012) and the species are also keyed in Whitworth (2006).
Range maps were constructed using SimpleMappr (Shorthouse 2010) on the basis of specimen records in the University of Guelph Insect Collection database, the collection of Terry Whitworth, the BOLD SYSTEMS database, and the Canadian National Collection of Insects. Specimen photographs used in the key were taken using a Canon 35mm camera mounted on a Stackshot rail; multiple exposures were stacked into high depth of field images using HeliconFocus (https://www.heliconsoft.com). In some cases, images were cropped and edited for sharpness and contrast in Adobe Photoshop. Some genitalia photographs, as indicated, are from Tantawi & Whitworth (2014) and Tantawi et al. (2017). Photographs of living flies were taken by the third author. Terminology, unless otherwise specified, follows Rognes (1991) and Whitworth (2006).
Melanodexia (8 species; not treated)
Pollenia (6 species; not treated)
Angioneura (5 species; not treated)
Opsodexia (4 species; not treated)
Chloroprocta idioidea (Robineau-Desvoidy)
Chrysomya megacephala (Fabricius)
Chrysomya rufifacies (Macquart)
Cochliomyia aldrichi Del Ponte
Cochliomyia hominivorax (Coquerel)
Cochliomyia macellaria (Fabricius)
Compsomyiops callipes (Bigot)
Phormia regina (Meigen)
Protophormia atriceps (Zetterstedt)
Protophormia terraenovae (Robineau-Desvoidy)
Protocalliphora (28 species; not treated)
Trypocalliphora (1 species; not treated)
Bellardia bayeri (Jacentkovskỳ)
Bellardia vulgaris (Robineau-Desvoidy)
Calliphora alaskensis (Shannon)
Calliphora aldrichia (Shannon)
Calliphora coloradensis Hough
Calliphora genarum (Zetterstedt)
Calliphora grahami Aldrich
Calliphora latifrons Hough
Calliphora livida Hall
Calliphora loewi Enderlein
Calliphora montana (Shannon)
Calliphora stelviana (Brauer & Bergenstamm)
Calliphora terraenovae Macquart
Calliphora vicina Robineau-Desvoidy
Calliphora vomitoria (Linnaeus)
Cyanus elongata (Hough)
Cynomya cadaverina (Robineau-Desvoidy)
Cynomya mortuorum (Linnaeus)
Lucilia bufonivora Moniez
Lucilia cluvia (Walker)
Lucilia coeruleiviridis Macquart
Lucilia cuprina Wiedemann
Lucilia elongata Shannon
Lucilia eximia (Wiedemann)
Lucilia illustris (Meigen)
Lucilia magnicornis (Siebke)
Lucilia mexicana Macquart
Lucilia sericata (Meigen)
Lucilia silvarum (Meigen)
Lucilia thatuna Shannon
We thank Tarek Tantawi and Jim O’Hara for the loan of specimens from the Canadian National Collection of Insects, and we acknowledge the contribution of other past and present museum curators who allowed TW to visit their museums or sent him specimens (see Whitworth, 2006 for a full list). Finally, thanks to two organizations that helped fund this study, the North American Forensic Entomology Association and the American Board of Forensic Entomology.
Danks, H. V. 1981. Arctic arthropods. A review of systematics and ecology with particular reference to the North American fauna. Ottawa: Entomological Society of Canada, Ottawa.
Downes, W. L. 1986. The Nearctic Melanomya and relatives (Diptera, Calliphoridae): a problem in calyptrate classification. Albany, N.Y.: University of the State of New York State Education Dept. New York State Museum Bulletin #460.
Hall, D. G. 1948. Blowflies of North America. Thomas Say Foundation, London.
Hall, D. G. 1965. Family Calliphoridae. In: A. Stone, C. W. Sabrosky, W. W. Wirth, R. H. Foote & J. R. Coulson (Eds), A catalog of the Diptera of North America North of Mexico. United States Department of Agriculture, Agricultural Handbook, Washington, D. C.
James, M. T. 1970. A catalogue of the Diptera of the Americas south of the United States: family Calliphoridae. Museu De Zoologica, Universidade De Sao Paulo, 102:1-28.
James, M. T. 1953. Notes on the distribution, systematic position, and variation of some Calliphoridae, with particular reference to the species of western North America. Proceedings of the Entomological Society of Washington, 55:143-148.
Jewiss-Gaines, A., Marshall, S.A. and Whitworth, T.L. 2012. Cluster Flies (Calliphoridae: Polleniinae: Pollenia) of North America.Canadian Journal of Arthropod Identification No. 19, 15 February 2012. Available from http://www.biology.ualberta.ca/bsc/ejournal/jmw_19/jmw_19.html.
Marshall, S.A., Whitworth, T., and Roscoe, L. 2011. Blow flies (Diptera; Calliphoridae) of eastern Canada with a key to Calliphoridae subfamilies and genera of eastern North America, and a key to the eastern Canadian species of Calliphorinae, Luciliinae and Chrysomyinae. Canadian Journal of Arthropod Identification No. 11, 11 January 2011. Available from http://www.biology.ualberta.ca/bsc/ejournal/mwr_11/mwr_11.html.
Picard, C.J. 2013. First Record of Chrysomya megacephala Fabricius.(Diptera: Calliphoridae) in Indiana, USA. Proceedings of the Entomological Society of Washington, 115: 265-267. Available from https://doi.org/10.4289/0013-87188.8.131.525.
Rognes, K. 1991. Blowflies (Diptera, Calliphoridae) of Fennoscandia and Denmark. E.J. Brill; Scandinavian Science Press Ltd., Leiden.
Rosati, J.Y. and VanLaerhoven, S.L. 2007. New record of Chrysomya rufifacies (Diptera: Calliphoridae) in Canada: predicted range expansion and potential effects on native species. The Canadian Entomologist, 139: 670-677. Available from https://doi.org/10.4039/n06-061.
Sabrosky, C. W., Bennett, G. F., & Whitworth, T. L. 1989. Bird blow flies (Protocalliphora) in North America (Diptera: Calliphoridae) with notes on Palearctic species. Washington DC, USA. National Museum of Natural History, Smithsonian Institution Press. Available from https://www.cabdirect.org/cabdirect/abstract/19910505851
Shorthouse, D.P. 2010. SimpleMappr, an online tool to produce publication-quality point maps. Available from http://www.simplemappr.net
Skoda, S. R., Phillips, P. L., & Welch, J. B. 2018. Screwworm (Diptera: Calliphoridae) in the United States: Response to and elimination of the 2016–2017 outbreak in Florida. Journal of Medical Entomology, 55.4: 777-786.
Tantawi, T.I. and Whitworth, T. 2014. First record of Lucilia bufonivora Moniez, 1876 (Diptera: Calliphoridae) from North America and key to North American species of the L. bufonivora species group. Zootaxa, 3881: 101-124. Available from http://dx.doi.org/10.11646/zootaxa.3881.2.1.
Tantawi, T.I., Whitworth, T.L. and Sinclair, B.J. 2017. Revision of the Nearctic Calliphora Robineau-Desvoidy (Diptera: Calliphoridae). Zootaxa, 4226: 301-347. Available from http://dx.doi.org/10.11646/zootaxa.4226.3.1.
Whitworth, T. 2014. A revision of the Neotropical species of Lucilia Robineau-Desvoidy (Diptera: Calliphoridae). Zootaxa, 3810: 1-76. Available from http://dx.doi.org/10.11646/zootaxa.3810.1.1.
Whitworth, T., & Rognes, K. 2012. Identification of Neotropical blow flies of the genus Calliphora Robineau-Desvoidy (Diptera: Calliphoridae) with the description of a new species. Zootaxa, 3209.1: 1-27. Available from https://www.mapress.com/j/zt/article/view/zootaxa.3209.1.1
Whitworth, T. 2010. Keys to the genera and species of blow flies (Diptera: Calliphoridae) of the West Indies and description of a new species of Lucilia Robineau-Desvoidy. Zootaxa, 2663: 1-35. Available from http://mapress.com/zootaxa/2010/f/zt02663p035.pdf.
Whitworth, T. 2006. Keys to the genera and species of blow flies (Diptera: Calliphoridae) of America north of Mexico. Proceedings of the Entomological Society of Washington, 108: 689-725.
Whitworth, T. 2003. A new species of North American Protocalliphora Hough (Diptera: Calliphoridae) from bird nests. Proceedings of the Entomological Society of Washington, 105: 664-673.
Whitworth, T. 2002. Two new species of North American Protocalliphora Hough (Diptera: Calliphoridae) from bird nests. Proceedings of the Entomological Society of Washington, 104.3: 801-811.
Yusseff-Vanegas, S. & Agnarsson, I. 2016. Molecular phylogeny of the forensically important genus Cochliomyia (Diptera: Calliphoridae). ZooKeys, 609: 107–120. Available from https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4984421/
Jones, N., Whitworth, T., & Marshall, S.A. 2019. Blow flies of North America: Keys to the subfamilies and genera of Calliphoridae, and to the species of the subfamilies Calliphorinae, Luciliinae and Chrysomyinae. Canadian Journal of Arthropod Identification 39: 191 pp. doi:10.3752/cjai.2019.39