This striking photo depicts a family of native Hawaiian "happyface spiders" (Theridion sp.) eating a syrphid fly (a non-native insect) at Auwahi (East Maui, Hawaii, USA). They're all perched on a native Myrsine sp. leaf.

USGS/BRD photo (so it's copyright-free; if you use it, please credit USGS/BRD & the photographers, Forest & Kim Starr); higher-resolution version [400+kb] also available.