Of ladybirds great and small

Everyone likes ladybirds, right? Certainly they’ve been a flagship group for citizen science, and often appear in art and lifestyle products a (wellies, umbrellas, jewellery…). My info is out of date, but I am pretty sure that someone from iSpot told me that Harmonia axyridis, the harlequin ladybird, is the single most frequently posted species on iSpot. I guess it’s the way ladybirds obvious, colourful, and don’t bite/sting/fly in your face with long gangly legs.

They’re a good group for people trying to learn insect ID, at least in the UK. There are apparently 46 species in the UK, which is a manageable sort of number, and 26 of them are obviously ladybirds and big and conspicuous enough to start recording even for a relative beginner. There are lovely identification resources available from the Field Studies Council and the UK Ladybird Survey – including ID of larvae, which adds a new element of excitement to the process, as ladybird larvae are pretty cool creatures too.

But…if we have 46 species, and 26 of them are “obvious”, what of the other 20? Well, that’s a whole new adventure, and if you ask me, an even more exciting one. Many of these species are considered rare, scarce or notable in some way…but whether they’re really that uncommon, or whether they’re just under-recorded and often missed in standard surveys is a good question.

Of the “micro-ladybirds”, one of the cutest is the horseshoe or inconspicuous ladybird, Clitostethus arcuatus. Up close, it’s definitely a ladybird…after a fashion. But it’s a far cry from a familiar seven-spot! For one thing, it’s about 2mm long. For another, it’s brown. For another, it’s hairy. But otherwise…definitely a ladybird.

Clitostethus arcuatusScreen capture from a BBC South-East report featuring the little chaps.

The adults and larvae are hungry little predators, though for Clitostethus the prey of choice is not aphids but whitefly (especially larvae). It was thought to be extremely rare, but then Simon Springate found it near Dover…and then we went looking on ancient woodland and other habitats all around Kent and kept finding it again and again. It might not be in every ancient woodland we check (inland ones in Kent seem a bit too cool), but certainly there seems to be a checklist of features that make finding a few Clitostethus quite likely. I’ve seen it in the wild on honeysuckle (eating honeysuckle whitefly), on wild cabbage (eating cabbage whitefly), and by some amazing fluke, in my father’s back garden on Welsh poppy, which is another host for honeysuckle whitefly. In Kent it seems to be mostly likely to turn up on a good, old, established thicket of honeysuckle in a nice warm, sheltered bit of ancient woodland, ideally in mild climatic regions (such as Kent coastal areas), and the best time to look is September. In winter, it can sometimes be found on ivy in sheltered nooks and crannies. The larvae are relatively immobile and white – but you can get away with not moving too fast when your prey are 0.5mm long immobile whitefly larvae!

Clitostethus seems to be at the northern edge of its range in the UK, with the most northerly records from Yorkshire and the Manchester area. Mostly, it’s been seen in the south-east…but I suspect there’s a good chance we’d find it in the south-west too if we went looking. So is it rare, or just under-recorded? Is it just that its habits make it hard to pick up by conventional sampling methodologies?

One of my other favourite micro-ladybirds is Scymnus interruptus. It’s a tiny bit bigger and a bit more generalist in its habits than fussy Clitostethus, and once you get close enough to see it, it’s quite unmistakeable – two triangular red marks, one on either elytra. They’ll nibble at whitefly, aphids, whatever’s going.

Scymnus interruptus on Stachys
Scymnus interruptus on Stachys

Scymnus interruptus adults pootling around on Stachys

The larvae are absolutely amazing. They look like a 2mm long version of one of those fluffy telescopic dusters on a stick you can buy. And by goodnesss, they can move! We’ve affectionately nicknamed them “Zoom larvae” because, relative to their size and given they’ve hardly even got legs, they can certainly zoom! Unfortunately, all the Scymnus larvae are pretty much the same, so you need adults to ID really.

Almost all the records for S. interruptus in the UK so far are from the south-east. Our area seems to be a bit of a stronghold…which may be why we’ve got a little colony in the garden. At this time of year, if I wander outside in the evening after work, I’ve got a good chance of finding two or three without putting a lot of effort in (the other day I managed a new record of six at once). They seem particularly fond of the Stachys, for some reason (it does host tiny aphids), although they’re also partial to our strawberry plants (probably reflecting the aphid infestation we developed in spring).

Scymnus interruptus on Stachys

Still pootling…

S. interruptus isn’t even the only Scymnus in our tiny 20m2 garden. We’ve also seen two other species from the genus, the redder (and more common) S. suturalis, and the blacker and larger S. femoralis, the female of which has a rather endearing red head.

Scymnus suturalisScymnus suturalis

Scymnus femoralisScymnus femoralis

A similar Coccinellid group, which we sadly haven’t seen in our garden yet, but have seen munching on scale insects at a local bus station, is the genus Nephus. They’re a bit bigger than Scymnus, and you have to double-check the shape and position of the red patches to avoid confusion (Nephus quadrimaculatus, for example, can superficially resemble S. interruptus, but has four red patches rather than two, they don’t reach all the way to the outer edges of the elytra, and are less triangular).

Are we doing something magical? Personally, I doubt it. Yes, we’ve got lots of wildflowers and generally a good diversity of plants relative to the total area available, the garden is quite sheltered, and we don’t use pesticides, but I suspect the secret is just sitting and looking, and paying attention to the small things. How much wonder exists in even the smallest outdoor space.

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