megacephala (Fabricius)

Musca megacephala Fabricius, 1794: 317 .

Chrysomya megacephala: Peck 1996: 122 [mode of introduction]; Peck et al. 1998: 228 [introduced species]; Causton et al. 2006: 133 [introduced species]; Tantawi & Sinclair 2013: 238 [review].

Distribution. Introduced. Afrotropical, Palaearctic, Neotropical; Galápagos: Baltra, Caamaño, Isabela, Santa Cruz.

Remarks. This species has purely saprophagous larvae that frequent carrion, refuse, faeces, meat and other food stuffs, and they can be common in markets (Baumgartner & Greenberg 1984; Wells & Kurahashi 1997). This species was first recorded from Isabela and Santa Cruz in 1989 (Tantawi & Sinclair 2013). It is suggested that Ch. megacephala is a stronger competitor against Cochliomyia macellaria in the presence of Ch. albiceps, leading to drastic decreases in populations of Co. macellaria (Wells & Kurahashi 1997); all three of these species occur in the Galápagos.