Fascinating Evolution

trilobite beetle

I am now happily back to my rainy season bugging forays into the forest and thoroughly enjoying the fascination of it all.

 There is always a sense of anticipation when bugging, every leaf you inspect could host a small find, whether that find will hang around for you to photograph him or her is always questionable and one has to adopt their own techniques to each situation just to approach many arthropods. Its not as easy as one might assume.

And even if you strike lucky and get a shot you are happy with, the thrill of the chase is still not over. You still have to attempt an ID. This can be a long and oft times doomed process as you consider Orders – Families – Genus - Species. Taxonomic Orders are usually easy enough. Families can be sometimes difficult. Genus is really what you are aiming for as a minimum identification level for your find, and if you can ID to Species level you have fully succeeded in your difficult task.

I consider it a successful ID if I manage to convince myself of Genus but am often stuck at Family. With an estimated “1 in 10” of arthropods only being actually scientifically identified at species level there are literally millions of proverbial curve balls that can fool you. And of course there are species whose differences from others cannot be seen with the human eye and may be only confirmed by a scientist using dissection and a microscope.

It is the ID process that makes the thrill of insect photography even more enjoyable, because to hunt down an ID we now have a myriad of helpful internet sites and tools to immerse ourselves in. And it is this immersion, this exploration, this journey, that slowly increases our knowledge of the fascinating world of arthropods. A world were wonder exists and the truly amazing avenues and alleyways of evolution reveal themselves.

And the best ID searches are for those arthropods you photograph and you think – “what the hell is that”! This last rainy weekend in Kaeng Krachan National Park I had two such finds. Finds that confused me but in searching for their IDs my knowledge was increased and my amazement at evolution was reinforced.

To start with was my first ever sighting of a female of a Net-winged beetle commonly referred to as a “trilobite beetle”, named so because of their prehistoric shape. The one you see here is Platerodrilus ruficollis. Platerodrilus is a genus of beetles of the family Lycidae. It was just sat on a vine about 50 cm above the forest floor on a hillside. I believe she had taken a position there to release pheromones in order to attract a male. What makes her so amazing is her difference from the male – she retains the overall form of a larval stage but the male continues to evolve into a “regular” beetle form. Another strange fact is that she dwarfs the male in size, she was around 50 mm in length, whereas the male may only be up to 20 mm. Now that’s a funky beetle.


A typical male Lycidae net-winged beetle - a normal beetle shape



And then, tiny by comparison, I happened upon a tiny concealer moth of the sub-family Stathmopodinae (also known descriptively as curved-horn moths), in the family Oecophoridae in the superfamily Gelechioidea of the order Lepidoptera (butterflies and moths). He/she was just some 8 mm long and I have to be honest - my aging eyes don’t see much detail at that length and I did not fully appreciate how exotic looking it was until I had chance to zoom in on the camera’s viewing screen. It was a very pleasant surprise. One can only marvel at why evolution has crafted it so.

A Stathmopodinae Moth

Stathmopodinae moth commonly called a curved-horn moth




Go forth and explore Thailand's wonders!


Interesting links:

  1. NATURE IN SINGAPORE 2008 1: 175–178 Author: A. F. S. L. Lok
  2. Scientific American - March 31, 2014. Author: Bec Crew
  3. RAFFLES BULLETIN OF ZOOLOGY 62: 136–145 Authors: Michal Masek, Michael A. Ivie, Vaclav Palata & Ladislav Bocak


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