A Hatch of Harlequins

For a recent ladybird walk I popped a few specimens in tubes so I could do the "Here's one I found earlier" trick if necessary (thankfully not needed, we found plenty of ladybirds). On returning home, I found a couple of the Harlequin Ladybirds, Harmonia axyridis, I had taken to show the three main colour forms had laid eggs in the pots.  I released the females and decided to document the development process. 

Five days after laying the first change could be seen, a slight darkening of the eggs and the legs visible down one side of the egg. Six and a half days after being laid, the larvae emerged. Emergence was well synchronized, designed to prevent their highly carnivorous siblings eating the unhatched eggs. 

On hatching, the larvae hungrily chowed down on the egg shells for a few hours, but it clearly wasn't going to be long before they started on each other. I'm not sure how to feed first instar larvae, which are a bit small for most aphids. There are various artificial diets published but research papers show these are a poor substitute for natural foods, so the simplest solution would be to let them cannibalise each other and then move the strongest larvae on to aphids for subsequent instars. I have little experience rearing insects and my few attempts have been fairly unsuccessful, so because I was feeling quite protective of my little house guests I distributed them across our aphid-infested Honeysuckle where they will do some good. I like to think they didn't get such a rough deal, protected from a pretty awful week's weather and, more importantly, all those nasty Ichneumons, before being freed to go about their lives.