Some notes by Jorge Almeida (jorgemotalmeida) on distinguishing the various types of greenbottle fly, taken from a comment at diptera.info:
Yes. It is. Several things point out to Lucilia sp. (I will show several features that can appear in similar flies but belonging to some different families or in some cases in the same family Calliphoridae):
- face/forehead not metallic green or bright yellow, not particularly bristly (otherwise it could be a Muscidae - Neomyia - specially the part of a strong green metallic colour around the ocellar zone; of course it should be verified other features)
- very well developed bristles on scutum (otherwise it could be a Chrysomya)
- Medial vein sharply bent towards vein R4+5 (NOT visible in the photo! Only with a good dorsal view.)
- Eyes bare; discals absent; weak abdominal bristles (it could be a Gymnocheta with strong abdominal bristles and hairy eyes - once again - it should be verified other features to be sure about Gymnocheta - it is a Tachinidae, in general, it is easy to recognize tachinids..)
(Jorge also has some good diptera ghotos up at Flickr (under the name superregnum).
For identifying greenbottle flies also see the photos in this post by Tim Worfolk.