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another view isn't helpful unless the cerci surstyli are visible.

The coxopleural streak is necessary in order to separate caesar, illustris and ampullacea sans genitalia. If a coxopleural streak is present and the hypopygium is smaller, then you have illustris. caesar has a very large hypopygium.

you can collect Lucilia and view them alive with a microscope.

I've attached a photo of the cerci and surstyli of caesar.