A pair of alderflies, Sialis sp (Megaloptera: Sialidae) mating.

Photo taken in Whiteknights Park, Reading, UK, on 2013-05-12.

What I think is a female Melanogaster sp (Diptera: Syrphidae).

Photo taken in the field below Chazey Wood, near Caversham, UK, on 2013-05-11.

A female Macquartia grisea (Diptera: Tachinidae).

Photos taken in the field below Chazey Wood, near Caversham, UK, on 2013-05-11.

A male Dilophus febrilis (Diptera: Bibionidae).

Photo taken in the field below Chazey Wood, near Caversham, UK, on 2013-05-11.

What I think is a female Anthomyia plurinotata (Diptera: Anthomyiidae).  This identification has been confirmed by Johanna van Erkelens here at Diptera.info. This species is apparently not on the UK checklist but it is on the Belgian one so it wouldn't be a big jump for it to get here.

Photo taken in Whiteknights Park, Reading, UK, on 2013-05-12

A rather docile male blowfly, probably a Bellardia sp (Diptera: Calliphoridae).  I captured this specimen and later took the following photos (before I released it again):

These show the greenish abdomen more clearly.

First photo and specimen taken in the field below Chazey Wood, near Caversham, UK, on 2013-05-11.

A female Hybos sp, possibly Hybos culiciformis (Diptera: Hybotidae).

Photos taken in Whiteknights Park, Reading, UK, on 2012-10-12.

Blue leaf beetles, probably an Altica sp (Coleoptera: Chrysomelidae) on a willow herb (Epilobium sp).

Photo taken on the dam at the lower end of the large lake, Whiteknights Park, Reading, UK, on 2013-05-06.

A male Empis sp, probably Empis trigramma (Diptera: Empipidae).

Photo taken in Whiteknights Park, Reading, UK, on 2013-05-06.

A Nematogopon sp (Lepidoptera: Adelidae).  Not my first longhorn moth of the year, that was a male Adela reaumurella I saw two days earlier. but the first I managed to photograph.

Photos taken in the Wilderness, Whiteknights Park, Reading, UK, on 2013-05-06.