Monday, 31 March 2014

And it was all yellow

The yellow flash is very often literally just a flash of yellow; the 
moment you see it, it's off into the treetops. It almost seems to be 
a rule: when you are rare, you must play hard to get. Most of my 
encounters with it were short lived ones of individuals who must
have seen me coming long before I spotted them. I bumped into a 
colony of them two weeks back and that was when I got lucky.

There were at least five of them in the area. While most of them
perched high up, out of reach and watching as I searched high and
low for them, some would fly down to the lower leaves and grasses.
They are bright yellow but are almost impossible to see amongst the
grass. Whenever one took flight, I would track it but it would always 
land 'somewhere over there'. In other words: it would disappear.

It is the odd one out in the genus rapala (the flashes). No other 
species has the same lemon-yellow colouration with the strange 
black blobs and streaks. It is also the largest flash in Singapore
and Malaysia, with a wingspan of around 30-40mm. It is rare here, 
showing up occasionally here and there in forested areas. 

Both the male and female are plain brown on the upperside and 
are almost impossible to distinguish, apart from the fact that the
outer edge (termen) of the wings are more rounded in the female
and a pale brand on the male's upperside. Since their wings are 
pale on one side and dark on the other, they seem to sparkle as
the fly. Strangely, the yellow comes out whitish when camera
flash is used, but only if the flash didn't already spook it off!

There are many speedy fliers in the butterfly world but the yellow
flash has to be one of the top racers. They zoom around at blinding
speeds and are quick to dart into the treetops at the slightest of
disturbances. Camera flash is another enemy of this butterfly.They 
are not very friendly to photographers! The yellow flash is also 
known to rest under leaves but I didn't see any doing that.

While the yellow flash is seldom seen, it appears seasonally in
in different locations, with several individuals congregating there
and only to vanish without a trace a week later. Yesterday I went
back to the hot-spot, only to find that the place was quiet! I hope
I'll meet this lovely little flash again sometime. 


  1. Well done Jonny for getting such great photos. It sounds like you were in the right place at just the right time! Lycaenidae is my favourite family, but Eruema is my favourite genus, so if I was ever to see a Yellow Flash it could become my favourite all-round butterfly! On my monitor the picture of the Yellow Flash is right next to your Random Butterfly picture of a Common Red Flash in almost exactly the same pose. It makes a good comparison.

  2. Wow! Wow! Wow! They are just stunningly beautiful. I'm so glad you were able to get such great shots, especially since they are so difficult to photograph. How exciting.

  3. Nice shot Jon. I love your opening shot. It's solid, as usual.

  4. Nick: I thought you'd say something about Eurema!! :)

    The yellow flash is really spectacular. And yes, the Red and Yellow flashes look quite different don't they? There still are similarities between the two though.

  5. Sylvia: Aren't they wonderful? Thanks for coming by again. It really heartens me. I think that I was lucky too because I can't find them anymore!! It'll be a while till they turn up again.

    Brian: Thanks!! I'm certain that you'll see it soon too.