Helophilus pendulus (Linnaeus 1758)

I realise that there have been a lot of invertebrates lately... I'll interrupt this with a reptile or amphibian soon... but not today.

Onwards!

(Bear in mind that 'not a...' sections are incomplete, and intended as a rough guide to what an organism is not rather than a detailed map)
Eukaryota - not a bacteria (Prokaryota) or a member of the Archaea
  Animalia - not a plant, a fungus or a member of any of the various Protist groups
    Eumetazoa - not a sponge...
      Bilateralia - not a coral, jellyfish, etc (Radiata or Cnidaria)
       Nephrozoa - not an acoelomorph flatworm (Acoelomorpha), usually.
          Protostomia - not a vertebrate, sea-squirt, or echinoderm (all Deuterostomia)...
            Ecdysozoa - not a mollusc or any of various worms...
              Arthropoda - not a nematode worm either...
                Hexapoda - not a millipede (Myriapoda), Spider, Scorpion or horseshoe crab (Chelicerata) or Crustacean.
                  Insecta - not a springtail (Collembola)
                    Dicondylia - not a jumping bristletail (Archaeognatha)
                      Pterygota - not a bristletail or silverfish (Thysanura)
                        Manopterygota - not a mayfly or extinct relative (Palaeoptera)
                          Neoptera - not a dragonfly or damselfly (Odonata)
                            Eumetabola - not a cockroach, termite or mantis (Dictyoptera), cricket or grasshopper (Orthoptera), Earwig (Dermaptera) or stick insect (Phasmatodea).
                              Endopterygota - not a true bug (Hemiptera) or bark-louse (Psocoptera)
                                Panorpida - Not a beetle (Coleoptera), Wasp (Hymenoptera), Lacewing (Neuroptera), snakefly (Raphidioptera) or alderfly (Megaloptera).
                                  Antliophora - not a butterfly or moth (Lepidoptera) or Caddis-fly (Trichoptera).
                                    Diptera - not a scorpion fly (Mecoptera) or flea (Siphonaptera).
                                      Brachycera - not a crane-fly or mosquito (Nematocera)
                                        Muscomorpha - not a horse-fly (Tabanomorpha) or Robber-fly (Asilomorpha)
                                          Aschiza - not a house-fly, blow-fly, grass-fly, fruit-fly or various other Schizophora
                                            Syrphoidea - not a coffin-fly or relative (Platypezoidea)
                                              Syrphidae - not a 'big-headed fly' (Pipunculidae).
                                                Eristalinae... not a member of Syrphinae (most hoverflies) or Microdontinae (a small, atypical subfamily of hoverflies)
                                                  Eristalini...
                                                    Helophilina... not a member of the Eristalini, the drone-flies...
 

Helophilus pendulus

(Linnaeus 1758)

     

 

Known to some as 'The Footballer', apparently due to its boldly striped thorax. On that basis, I'd be tempted to call it 'The Ref' instead... but Helophilus (~Heh-loh-fill-us - literally 'bog-lover', due to its association with damp habitats) is easy enough to say, and avoids the complications inherent to 'I just saw a footballer in the pond'. 

Their bright colours seem to serve the purpose of convincing potential predators that they are dangerous, when, in fact, they are harmless (Read: no sting, no bite) pollinators with filter-feeding larvae. Of the several British species of Helophilus, this species is by far the most common.

That's all, folks.

(Identified by comparison of leg and abdomen colouring to images of known members of the genus with overlapping ranges. No specific site or reference employed).