Hoverfly

A black hoverfly covered if fine white hairs and with dark patches on its wings.  A male Pipiza sp, probably either P. austriaca, P. lugubris or P. noctiluca (Diptera: Syrphidae).

Photos taken in Whiteknights Park, Reading University Grounds, Reading, UK, on 2011-6-13.

Horsefly

Horsefly Haematopota pluvialis (Diptera: Tabanidae).  The bane of my walks of late: buzzing around and settling on my trouser legs but occasionally landing on my hands and giving quite a painful bite.  Even on the warmest days I wear a long-sleeved rugby shirt to protect my arms from these little pests!

Photos taken in Whiteknights Park, Reading University grounds, Reading, UK, on 2011-07-04.

State Transfer

From Architectural Styles and the Design of Network-based Software Architectures, the PhD dissertation of Roy T. Fielding, page 109 (2000):

"The name “Representational State Transfer” is intended to evoke an image of how a well-designed Web application behaves: a network of web pages (a virtual state-machine), where the user progresses through the application by selecting links (state transitions), resulting in the next page (representing the next state of the application) being transferred to the user and rendered for their use."

Thus, it is the state of the whole application that is being transferred in REST, not the state of particular resources as suggested here.

Ichneumon Wasp

An ichneumon wasp checking out a caterpillar of the cinnabar moth, Tyria jacobaeae (Lepidoptera: Arctiidae), presumably as a potential host for an egg.  This time the caterpillar was lucky and the wasp flew away after the caterpillar waved its head about a bit.

The wasp looks similar to this one I photographed a few days ago checking out a caterpillar of the moth Depressaria daucella.  I suspect they both might be member of the Anomaloninae (Hymenoptera: Ichneumonidae).  See here for further pictures of this group.

Photo taken in the field below Chazey Wood, near Caversham, UK, on 2011-007-02.

Identifying Greenbottle Flies

Some notes by Jorge Almeida (jorgemotalmeida) on distinguishing the various types of greenbottle fly, taken from a comment at diptera.info:

Yes. It is. Several things point out to Lucilia sp. (I will show several features that can appear in similar flies but belonging to some different families or in some cases in the same family Calliphoridae):

• face/forehead not metallic green or bright yellow, not particularly bristly (otherwise it could be a Muscidae - Neomyia - specially the part of a strong green metallic colour around the ocellar zone; of course it should be verified other features)
• very well developed bristles on scutum (otherwise it could be a Chrysomya)
• Medial vein sharply bent towards vein R4+5 (NOT visible in the photo! Only with a good dorsal view.)
• Eyes bare; discals absent; weak abdominal bristles (it could be a Gymnocheta with strong abdominal bristles and hairy eyes - once again - it should be verified other features to be sure about Gymnocheta - it is a Tachinidae, in general, it is easy to recognize tachinids..)

(Jorge also has some good diptera ghotos up at Flickr (under the name superregnum).

Update on Tue 2012-03-13 by Tristram Brelstaff

For identifying greenbottle flies also see the photos in this post by Tim Worfolk.