GPSed. Upper insect in pic. The Incidental sighting - only noticed it after reviewing plant pic at home - hence resolution is not great. Based on flower dimension estimate length of fly ~3-4mm. Zooming in my own pic I'm confident that it has the colouring and 3 longitudinal marks on its pronotum and single longitudinal stroke on its head that characterise Sarcophagidae sp. (family) and from what I can see it seems to fit Sarcophaga sp. (genus).