Thread subject: Diptera.info :: Parasitoid larvae and caterpillar host

Posted by Alvesgaspar on 22-04-2010 00:12
#1

What is this? Is the caterpillar going to be eaten alive by the larvae or is it some form of commensalism? Taken today, in Lisbon. There were several, in vaious stages, going up the walls, in the outside.
Joaquim

Edited by Alvesgaspar on 23-04-2010 22:49

Posted by Alvesgaspar on 22-04-2010 00:13
#2

next photo...

Posted by Tony Irwin on 22-04-2010 00:19
#3

They are parasitoids - Apanteles glomeratus (Braconidae)

Posted by Alvesgaspar on 22-04-2010 00:32
#4

Thanks, Tony. If I understand well, the eggs were laid inside the cocoon by the wasp. But why is the caterpiller staying with its predators? Is it really going to be eaten?

Posted by Tony Irwin on 22-04-2010 23:55
#5

The eggs were laid in the caterpillar, so the wasp larvae have been eating it from inside. When ready, they emerge and spin cocoons under the caterpillar. Both the caterpillars you photographed are already mostly eaten inside.

Posted by Alvesgaspar on 23-04-2010 22:45
#6

Impressing, Nature is cruel! If I understaood well, the caterpillars will die. And why do them stay in the place even after the larvae formed the cocoons?

Posted by Tony Irwin on 24-04-2010 08:41
#7

When the larvae emerge and form cocoons, the caterpillars are more or less dead already. And it's just as well the braconids do this, otherwise we would never have any cabbage to eat!

Posted by Alvesgaspar on 24-04-2010 13:34
#8

Thanks again, Tony, now I understand. Yes, Pieris brassicae is a serious pest of cultivated brassicas!