Lucilia silvarum Meigen (Diptera: Calliphoridae) Is a Primary Colonizer of Domestic Cats (Felis catus).

Simple Summary: This study analyzed the initial blow fly colonizers of cats in August 2021 in Indiana. Lucilia silvarum was a primary colonizer of cats in this study, which was a surprising and unexpected finding. Lucilia silvarum has been referred to as a blow fly species that only performs myiasis on amphibians up until recently. In 2014, another blow fly species, Lucilia bufonivora, was discovered in established collections in North America. With this discovery, further reexaminations of fly specimens found that L. bufonivora has been in North America since the 1950s and that the specimens identified as L. silvarum were actually L. bufonivora. Given the history of L. silvarum and that this fly appeared as a primary colonizer of cats, the purpose of this research is to compile all the L. silvarum literature while bringing awareness to the forensic entomology community that this blow fly is forensically relevant. The implications of L. silvaurm being a primary colonizer will aid future investigations of animal abuse or cruelty. Correct identification of blow fly species is paramount when calculating time of colonization estimates. These estimates aid investigators in determining timelines regarding wounds or death. Lucilia silvarum Meigen (Diptera: Calliphoridae) is widespread throughout North America and Europe. Described in 1826, this blow fly was quickly associated with myiasis in amphibians, and to date has rarely been reported in carrion. There is limited data regarding the time of colonization of animals with fur and the interpretation of this data is difficult due to variation in the animal models used. During an examination of initial insect colonization of cats (Felis catus) with light and dark fur, twelve domestic short-haired cats were placed in cages 15.2 m apart in a grassy field in West Lafayette, Indiana, USA. Eggs from initial oviposition events were collected and reared to identify the colonizing species. Three species of Lucilia (Diptera: Calliphoridae), including L. silvarum, colonized the cats on the initial day of placement. In this study, L. silvarum was the primary colonizer of cats, and this may be the first study where a large number of L. silvarum were collected. Further studies should include development studies on L. silvarum to understand its life history and aid in time of colonization estimations. More work regarding the colonization of furred mammals is needed to further examine L. silvarum as a primary colonizer. [ABSTRACT FROM AUTHOR]