Thursday, 23 September 2010

Better......Better Get a Bucket.......

WARNING: You might not want to click on the videos below - they are just a tad icky (and that is the biggest understatement of the year!)

My last Macro Monday post was a bit of a challenge - you had to identify a disgusting looking specimen that one of my colleagues at work had found. Now this beast is not one of the ugly ducklings of this world, destined to metamorphose into a beautiful creature that we can all love and admire. Nope, this animal is repugnant as a larva and not-so-nice as an adult. However, the adult is still a vast improvement over the immature.

So, today, we are talking botflies. I am pretty sure that this monstrosity is one of the best arguments against the existence of god or, if there is a god, against him being a benign, loving and forgiving sort. For the botfly really is disgusting. As an adult, it is a large, hairy fly whose sole mission in life is to reproduce. It has no functioning mouthparts, does not eat and only lives for a few days. Once mated, its goal is to find a host for its impending offspring. There are a couple of ways that it can do this. Some species lay their eggs directly on their intended victims or close by to where the victim will be. The eggs are stimulated to hatch by the warm bodies and the carbon dioxide breathed out by the soon-to-be incubators. Other botflies are even more cunning. Since they are large flies, if they land directly on their targets, they will often be felt and brushed aside. So, instead of depositing the eggs directly on the host, they actually catch a smaller fly. They grasp this fly with their legs and attach their eggs onto the fly's abdomen. When this fly lands on a likely candidate, it is less likely to be noticed and, once again, warmth and carbon dioxide cause the eggs to hatch. Pretty cunning, uh?

Adult botfly, photo is from here.
OK, so now we come to the really gross part. The larvae. These maggots live just underneath the skin of their host. Once hatched, they bury themselves headfirst in the host's body, just leaving a small hole for the tip of their abdomen to peak through. This hole gives them access to air and, since they really are disgusting, what better way to breathe than through their bums. Each segment of the botfly maggot is encircled with a row of backward pointing spines to make sure that the little bugger is firmly held in place and is very difficult to remove. The maggot can now happily munch away on the oozing flesh of the poor unfortunate critter whose misfortune has led it to be infested by this delightful creature. Once it is full grown, it will pop out, Alien style, drop to the ground and pupate, eventually emerging as an adult fly.

Young botfly maggot, photo is from here. As you can see, the young larvae are soft and yellow, with lots of spines.
Mature botfly maggot

So, there you have it. If the above has not disgusted you quite enough, then have a look at these videos. The second one was very "kindly" sent to me from Katherine, over at The Last Visible Dog. Thank you Katherine, that was so sweet of you - NOT!

What kind of god could come up with these things? I mean, really!?! Oh, and don't forget - DON'T watch these videos if you have a weak stomach. If you do and you still want to watch them, go and get a bucket first, just in case.





Are you still here? Crikey! Perhaps you didn't watch the videos. Anyway, I thought that I should point out that my specimen, found here in Beautiful British Columbia, belongs to the genus Cuterebra and is a parasite of mainly rodents such as squirrels and rabbits. The main place for human botflies is Central America and some of South America, so you can sleep tight tonight, unless you live there or have recently been there ............. oh crap......... I would have noticed one by now, wouldn't I?

6 comments:

Cortes said...

It truly is a disgusting bug! I decided not to watch the videos, being a little squeamish, and just having finished dinner. But I did have one thought, and that is that if I could have breathed through my bum I could have been quite a competitive breaststroker!

Susannah (Wanderin' Weeta) said...

That poor dog!

Rita Fantham said...

Thanks for sharing that...not!! Shall keep my Ellie miles away from any of those little darlings...

English Mum said...

I've just sat here - all alone - wetting myself at Cortes' comment for about the last five minutes. Classic.

And yes, that poor dog. x

Don't Bug Me! said...

Four comments!?! Is that all I get? I am never going to win a Canadian Blog Award with so few readers! At least Cortes is keeping EM amused. He would keep me amused if it wasn't for the fact that he keeps making not so useful suggestions on getting my house finished.

Cortes: Oh, go on, watch the videos .......... you know you want to.....

Susannah: I know. Kind of reminded me of squeezing spots in my younger days. Not that my spots wriggled off once they had been squeezed, but you know what I mean. OK, I'll stop typing now.

Auntie: Sorry, but I did warn you.

EM: He is quite the amusing chap, isn't he?

Mike B. said...

OK- now I want to vomit- and I have a pretty high tolerance for that stuff!