Down by the lake the other day, my favourite willow was positively covered with large purple aphids making their way up the trunk—and the air was alive with swarms of tiny parasitoid wasps (family Braconidae) preying on them! Here is one injecting an egg into an aphid. The aphids become swollen husks as the wasp hatches, feeds, and pupates, eventually cutting a neat hole and emerging as an adult, ready to continue the cycle. I have never seen the wasps emerging but hope to one day.

#bugstodon #insects #wasps #aphids #parasitism • #Hymenoptera #Braconidae #Aphidiinae