Infestation of a Naturally Incubated Nest of the Alligator Snapping Turtle (Macrochelys Temminckii) by the Phorid Fly Megaselia Scalaris (Notes) (Report‪)‬

Infestation of turtle nests by flies is a common phenomenon, with dipteran larvae reported from nests or eggs of multiple species of turtles (e.g., McGowan et al., 2001; Hall and Parmenter, 2008). Two dipteran families commonly reported in nests are Sacrophagidae and Phoridae. Larvae of Phoridae have been reported in nests or eggs of the green sea turtle (Chelonia mydas; Fowler, 1979; McGowan et al., 2001), hawksbill sea turtle (Eretmochelys imbricata; Bjorndal et al., 1985), loggerhead sea turtle (Caretta caretta; Broderick and Hancock, 1997; McGowan et al., 2001), eastern box turtle (Terrapene carolina; Ewing, 1933), Meso-American slider (Trachemys venusta; Moll and Legler, 1971), and painted wood turtle (Rhinoclemmys pulcherrima; AcunaMesei Mesen and Hanson, 1990). The phorid most commonly identified from nests of turtles has been Megaselia scalaris, a species in which the larvae feed on a broad spectrum of decaying organic matter (Disney, 2008). Megaselia scalaris is known as a scavenger, facultative predator, parasitoid, and parasite (Disney, 2008), so it can be unclear whether larvae of M. scalaris in nests of turtles are scavengers or parasitoids (Broderick and Hancock, 1997). This already confusing situation is further complicated by indications that M. scalaris is capable of attacking both developing and nondeveloping eggs (Acuna-Mesen and Hanson, 1990). It has been suggested that larvae of M. scalaris feed primarily on dead or weakened hatchlings (Fowler, 1979) and that adult M. scalaris may be attracted to odors associated with rotting nonviable turtle eggs (Acuna-Mesien and Hanson, 1990; Broderick and Hancock, 1997; Saumure et al., 2006). However, Moll and Legler (1971) reported that adult M. scalaris entered turtle eggs through tears made by pipping hatchlings and oviposited on eyes and yolk sacs of hatchlings, which subsequently died.