Sunday, 25 April 2010

Fly United

A pair of Stilt-legged Flies doing what Stilt-Legged Flies do. They are members of the Micropezidae, a family of about 50 genera and 500 species worldwide. They are most common in the tropics. This is species of Mimeogralla. The adult flies are not uncommon on leaf surfaces during the day where they hunt small insects such as Springtails. They make themselves obvious by waving their front legs in front and over their heads much in the manner of a wasp flicking its antennae. This may afford some protection form predators that might not like to take on a wasp. The larvae of this species are said to live on ginger roots. This seems a likely scenario as the adults were photographed on ginger leaves.

This pair seems to be a different species from the ones photographed below. Note the eye colours. The female is the lower fly and has her front feet tipped in white. Since they are held out in front to resemble wasp antennae it is noteworthy to mention that many invertebrates have either white-tipped antennae or white rings just below the tip of the antennae. I have always wondered what this means. I've seen it on several continents and even with an ichnemonid wasp with white subannulations on its very long ovipositor. Some information is being transmitted here but I can't interpret it. Take a look around your garden and see if you can find insects or other invertebrates with white-tipped antennae. I'm sure you will be successful.

Large eyes are important if you are a diurnal predator.

The mouthparts can be clearly seen on this fly. It consumes the contents of small insects by sucking them dry!

As long as we are on the subject of flies, the above is tiny member of the Dolichopodidae. This is a much bigger family with more than 7000 species in about 230 genera. Many are iridescent and glisten metallic green or yellow in the sun. They are very active and often have small, temporary territories. The adult feed on small insects. This little fly just did not want his photo taken from above and perfectly synchronised his flight with the operation of the flash. When confronted head-on, the fly did not flinch.

1 comment:

Denis Wilson said...

Hi Dave
Great series of Fly images. The last one looks spectacular, even though not clear. Sometimes an "effects shot" is great just for the look of it.
I will write to you shortly to sort out a couple of things I promised to do for you re Blogging format,and also an overdue Thank You note.