Tuesday, 25 October 2016


Odds are that the first beetle recognised or observed by a child will be a ladybird. At one time it would probably have been a Two-spot Ladybird, Adalia 2-punctata, or a 7-spot Ladybird Coccinella 7-punctata. Unfortunately today it is as likely to be a specimen of the aggressive Harlequin Ladybird, Harmonia axyridis - aggressive in that this recent arrival to our shores is partial to the larvae of other ladybirds (but also its own species).

In most areas the commonest ladybird is still the 7-spot, which has three spots on each wing-case (elytron, plural elytra) and one on the suture, i.e. the dividing line.  The spots are not present when the adult first leaves its pupa but develop within the first few hours.
Seven-spot Ladybird in my garden at Stefen Hill, Daventry.
12 June, 2016, above its black pupal case.
I photographed this specimen of the 7-spot in my back garden as it left the black pupal case; the elytra slowly took on a red coloration and the spots gradually appeared like a photograph being developed. This species in particular is aphidophagous but other species eat aphids too. In his book on ladybirds ('Ladybirds', Richmond Publishing, 1989) the late Michael Majerus divides the apparently defenceless aphids into kickers, walkers and droppers. The first group kick out at an attacking ladybird, the second group attempt to move away - apparently quite a successful strategy - and the droppers simply fall to the ground.
Anyway, I digress.
Calvia 14-guttata at Sixfields, Northampton. 2 June, 2016
Ladybirds come in a range of colours and this brown species, Calvia 14-guttata, was on a shrub near Sainsbury's at Sixfields, Northampton. It is quite frequent and is known as the Cream-spot Ladybird.
When I said that 'other species eat aphids', I implied that some had an alternative food source. Several species are herbivorous, and feed on mildew. The familiar yellow and black 16-spot Ladybird, Micraspis 16-punctata, is one such species, while the tiny 24-spot Ladybird, Subcoccinella 24-punctata, feeds on clovers and vetches.
Of course, the larvae of ladybirds are also distasteful and bear warning marks to deter birds and other would-be predators. The picture shows the almost fully-grown larva of a Harlequin Ladybird, Harmonia axyridis.

Larva of a Harlequin Ladybird, Daventry town centre,
24 May, 2016
Once the larva emerges from the egg it must find food quickly. The larva of the Two-spot Ladybird, Adalia 2-punctata, will only survive for about a day, perhaps a day and a half, before dying. It will survive on meagre rations but be smaller than a well-fed specimen.
I suppose around three quarters of the ladybirds I encounter are Harlequins and the remainder are largely Seven-spots, but occasionally others make an appearance. The Eyed Ladybird, Anatis ocellata, is nationally quite common but is largely confined to pine trees and their relatives.

Eyed Ladybird, Anatis ocellata, on a fence in Byfield, Northasnts.
25 October, 2016
When one turned up in Byfield I was quite surprised as I have not recorded it there before and pines in the area are few and far between. It is one of our largest ladybirds and each black spot is edged with a cream-yellow border, making it quite distinctive. I must be more observant.

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