React FlatList renderItem

I've seen this sort of syntax in JS before and I am just curious how it works. In the React Native Docs for FlatList, an example calls renderItem. How does this._renderItem know that what individual list item it is working with? It looks like item is being destructured, but from what object?

Put differently: in Flatlist, another way to make this same call could be:

<FlatList <other props> renderItem={({item}) => (<MyListItem ....) />

Is renderItem some special prop where {item} will always be the destructured arg?