Hoverflies

Hoverfly Volucella zonaria (Diptera: Syrphidae), a male from the side. And from above:

Note that the yellow bands are much darker towards the front of the abdomen.

A few seconds later the following similar hoverfly landed on a neighboring thistle flower head:

This a a male Volucella inanis (also Diptera: Syrphidae).  Here the yellow bands on the abdomen are all evenly yellow.

Photos taken in the field below Chazey Wood, near Caversham, UK, on 2011-07-22.