Monday, 18 August 2014

Species of the Week: Lysibia Wasps

You may have heard of the parasitic wasps that lay their eggs in an unfortunate host, but have ymaybe_ard of hyperparasitoid wasps? A hyperparasite is a parasite that parasitizes another parasite. That's exactlly what a Lysibia wasp does - they parasitize other parasitic wasps. Lysibia sp. have a curious relationship with brassicas, Small White butterflies, and Cotesia glomerata, a parasitic wasp.
It all starts with a Small White caterpillar feeding upon a brassica. In response to being eaten, the plant releases a chemical into the air, signalling its distress. When a female Cotesia glomerata wasp detects this chemical, it will come down and inject its eggs into the caterpillars. The wasp larvae emerge from the eggs and worm their way out from underneath the caterpillar's skin, killing it. What a horrible way to die!

A Small White (Pieris rapae) caterpillar

At this point the wasp larva will pupate, but they may not even get that far. The Lysibia sp. can also detect the chemical given off by the brassica, and so knows exactly where to go to find its host. The female will come and inject her eggs into the Cotesia larva or pupa, and thus the parasite becomes the parasitized.

A Lysibia female injects her eggs into Cotesia larva
Things can't get any more complicated, right? Wrong - because even the hyperparasitoid can become parisitized! Other Lysibia individuals will sometimes parasitize the larva of the same species, making it a hyperparasitoid and hyper-hyperparasitoid!
 A Lysibia sp. adult
This post turned out to be not so much about Lysibia itself, but the entire food chain.
I'm not sure if a hyper-hyper-hyperparasitoid exists, but I'm keeping an eye out for one!
Until next time, keep on the wild side!

1 comment:

  1. Amazing, thanks Jacob, you've taught me something new. :)