June 26, 2008
Ladybird larvae and the BBC!
Last week a film crew from BBC1's Countryfile visited the ladybird lab to do a feature on Harlequins. My job was to to take the crew to the Cambridge backs and bash lots of ladybirds out of the trees, to highlight the difference between the Harlequin and the native species. Needless to say adult ladybirds were very thin on the ground that day, and the only native species I found (a Pine) flew out of my beating tray before we could film it! Fortunately we did find some Harlequin larvae to talk about, so here's a mini-guide to the ladybird larvae I've encountered so far.
In the late larval stages (3rd or 4th instar), Harlequin larvae are very distinctive with their big spines and two bright orange stripes down the back. This one is engaging in intraguild predation, eating the pupa of another ladybird species (a 2-spot or 10-spot).
2-spot and 10-spot larvae can often be found in the same deciduous trees as Harlequins, but lack the spines of the latter species and typically have just a few orange splodges on the back. On average 2-spot larvae tend to be dark grey or black...
... while 10-spot larvae are pale grey.
Cream-spot larvae, distinguished by their cream spots against a dark body, are also deciduous tree-dwellers.
Much less frequently seen, these are, respectively, the larvae of the Larch and 18-spot ladybirds. Both are smaller and paler than the above species and normally occur on conifers.
7-spot larvae can often be found in long grass and have 4 pairs of orange spots against a black body.
14-spots are also grass-dwellers; the larvae are black with bold white spots and long spidery legs.
One of the most distinctive larvae is that of the 22-spot, a mildew feeder.
Finally, this cute, furry larva is a herbivorous 24-spot, lacking the aphid-grabbing mouthparts of its carnivorous cousins.
I believe the Countryfile episode is due to air on BBC1 on the morning of Sunday July 6th - I'll be the embarrassed-looking guy fluffing his lines while kneeling in front of a beating tray!
