Round-keeled Ladybird Rhyzobius chrysomeloides

Other names: Cryptic Brown Ladybird, Round-keeled Rhyzobius

This is the commonest ladybird in my recording area, occurring in pine trees, Ivy and ornamental evergreen shrubs.

It is also the only species that I can find, almost at will, on any day of the year.

It occurs in every garden with ornamental shrubs that I have searched.

It can easily be found wintering in Ivy, using a beating tray. A useful project during the quiet months of November-February.

Identification Length 2.5-3.5mm

A brown, long-bodied oval species with long antennae. Ground colour varies from deep chestnut to light oak with variable dark markings on the hind wing cases.

Varies from a few dark streaks to large dark patches and occasionally solidly dark.

A useful visual clue on the majority of specimens is a curved diagonal pale stripe on each front wing case area, (epaulets). These combine to form a U-shape, which is visible to the naked eye.

The sides of the pronotum, (between the head and wing cases), is strongly curved, sometimes forming a right angle on the corner and the rear edges are often straight and nearly parallel sided.

The clubbed antennae are thin, longer than the head width and often held towards the side.

They usually show a distinctive kink at the halfway point, resembling a wire coat hanger.

When disturbed Round-keeled Ladybirds often sit still with their legs and antennae tucked under the body, so need to be left until they start walking about before this feature can be checked.

1 brox rhyzobius chrysomeloides_4265.JPG

Broxbourne, Herts

2 upsh rhyzobius chrysomeloides_4717.JPG

Upshire, Essex

Upshire, Essex

Waltham Abbey, Essex

5 chingford rhyzobius chrysomeloides_183

Chingford, Essex

Waltham Abbey, Essex

3 thundridge rhyzobius chrysomeloides_16

Thundridge, Herts

Upshire, Essex

Fishers Green, Lee Valley, Essex

Upshire, Essex

With 7-spot Ladybird

With Cream-spot Ladybird

With 22-spot Ladybird

Beaten from Ivy alongside Opilo mollis and Pogonocherus hispidus Fishers Green, Lee Valley, Essex

On lid of garden wheelie bin Upshire, Essex

The prosternal keel (on the underside between the front pair of legs) is shaped like a narrow bell, rounded at the top and splaying out at the base, with a parallel sided mid-section.

Image taken with digital microscope

Upshire, Essex

Round-keeled Ladybird has a reputation for being difficult to identify and separate from the similar Pointed-keeled Ladybird. Whilst a few individuals show a confusing suite of characteristics, I believe the majority are quite easy to identify if all the different features are checked in combination.

If claiming a first County record, or a significant range extention, then it may be necessary to retain a specimen but in the species core range I am confident a good photograph is sufficient to identify the majority of individuals correctly. If over caution is used to prevent the claiming of Round-keeled Ladybird, we will never discover just how common this species is.

Habitat

Can be common in pine trees, in small copses or individual trees.

Plantation pine tree Upshire, Essex

Garden pine tree Upshire, Essex

Amongst pine needles Upshire, Essex

They can also be common on Ivy in woodland situations.

In the Lee Valley and around the northern edge of Epping Forest they can easily be found in winter by searching Ivy growing on tree trunks.

Ivy. Fishers Green, Lee Valley, Essex

Ivy. Hall Marsh, Lee Valley, Essex

Ivy Fishers Green, Lee Valley, Essex

Ivy. Cornmill Tree Park, Lee Valley, Essex

Ivy Hooks Marsh, Lee Valley, Essex

Ivy. Waltham Abbey, Essex

Round-keeled Ladybirds can be abundant in gardens, both rural and urban.

They can be found on Ivy covered fences and on a variety of evergreen shrubs, especially Euonymus, Viburnum tinus, Firethorn and Cotoneaster.

Euonymus. Upshire, Essex

Euonymus. Waltham Abbey, Essex

Euonymus hedge. Abbey Gardens, Lee Valley, Essex

Firethorn. Upshire, Essex

Oleaster Elaeagnus Waltham Abbey, Essex

Round-keeled can easily be found in garden wheelie bins that have been filled with the prunings from these shrubs.

They can also be found in deciduous shrubs, including Weigela and Guelder-rose.

I have also beaten them from low hanging oak tree branches.

Weigela. Upshire, Essex

Guelder-rose. Fishers Green, Lee Valley, Essex

Oak tree Potkiln Wood, Epping Forest, Essex

During July 2020 Mark Hows and I were beating either side of a foot path at Fishers Green, Essex and we were finding Round-keeled Ladybirds in almost all pieces of vegetation we sampled, including oak trees, thistles, burdock, White Bryony and Black Horehound.