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Monday, 31 August 2020

Sawfly

Large Rose Sawfly larvae (Arge pagana)
While checking over a corner of the garden for potential new denizens recently, I came across these orange-headed "caterpillars", munching enthusiastically on a rose leaf. Some internet research on Mike's part eventually attached a name: they're Large Rose Sawfly larvae. This is one of two sawfly species that attack roses in the UK. The larvae of the other species (the Rose Sawfly, Arge ochropus) are very similar. The big difference is that larvae of this species have pale hairs on their heads, while those of the Rose Sawfly have dark hairs. (You'll have to click on the picture above to see any trace of those hairs — or rather, the lack of dark ones.) In addition, the spot at the end of their abdomen is solid black; those of the Rose Sawfly have a pale centre. Adults are about 10 mm (4/10 of an inch) long. They're black on the thorax and orange on the abdomen, and have dark, tinted wings and black legs (many with some orange on the femur of their hind legs).

Sawflies are related to bees, wasps and ants. Unlike bees and wasps, they lack stingers. They're named for the distinctive ovipositor of the female. These egg-laying appendages have sawtooth edges, which allows the females to saw into plant stems to lay their eggs. Larvae often hang out together (as ours did), particularly while they're younger. They'll overwinter as pupa, to emerge as adults in the spring. Adults are primarily seen from March (in more temperate years) to June. The species is common throughout the UK, and found across the Palearctic to the Pacific Ocean. If they eat all of "our" roses (planted by the previous owners), we won't be upset. Neither of us are particularly fond of plants that bite back!
In defensive posture


Tuesday, 25 August 2020

Harvest(wo)man

Leiobunum rotundum

On my way out to the garage the other morning, I spotted this long-legged girl clinging to the bottom of the swallow nest platform, out of the sun. It's a female harvestman (harvestwoman?) belonging to the species Leiobunum rotundum, which has no common name. Though she looks a bit like a spider, with her eight long legs, she's not. Harvestmen (known as daddy-long-legs in the US) are closely related to spiders, but differ in having only a single body segment, rather than the two segments that spiders do. They have just two eyes, rather than the 6-8 that spiders have. You can just see her eyes near the right edge of the smaller (left hand) dark mark on her body; they sit on a tiny turret (called an ocularium). Click on the picture above to enlarge it, if you're having trouble finding them. The dark stripe down the middle of her body is unique, allowing her to be easily identified. The pale patch between her two dark-rimmed eyes is also a useful ID feature. With a body measuring some 7 mm long (1/4-inch) long, she's about twice the size of a male, which would lack the dark body stripe. 

Like all harvestmen, this is an ambush hunter, chasing down small prey including aphids, leafhoppers, flies, moths, spiders and woodlice. Unlike spiders, harvestmen will also feed on carrion and decaying plant matter. This is a common and widespread species right across the UK, though somewhat less so further north. Elsewhere, it widespread across most of Europe, though not around the Mediterranean. It prefers shady, moist habitats. Adults are found from July through November, so we should be seeing them around for a while yet. Ours is the first record for our part of Norfolk in the national database — woohoo!

Saturday, 22 August 2020

Woody

Eurasian Green Woodpecker (Picus viridus) - immature

We have a pair of Eurasian Green Woodpeckers (Picus viridus) somewhere in the village; we see them bounding over periodically, and hear them even more frequently. But they're wary and flighty, rocketing out of the garden as soon as they lay eyes on us, so it was a welcome surprise to get to spend some time with this youngster as it rummaged along the driveway a few weeks ago. It was slurping up the winged ants that were emerging from some of the ant nests in the garden wall. The heavy speckling on its breast and back — and the lack of black on its face — help to identify it as a youngster. Its colouring (primarily green) and size (largest of Britain's woodpeckers) help to distinguish it from the UK's two other woodpecker species, both of which are black and white. Primarily a ground feeder, it specialises on ants, though it will eat other invertebrates, fruit and pine seeds, particularly in the winter, when ants aren't readily available. Though it does spend time in trees, it seldom pecks at wood. Primarily a bird of southern Britain, it is common in England and Wales, quite scarce in Scotland and not found in Northern Ireland. Elsewhere (as its name suggests), it is found right across Europe and into western Asia. Hopefully, we'll be seeing this one, and its parents, regularly in the future.

Friday, 14 August 2020

Speckles

Speckled Bush-cricket nymph (Leptophyes punctatissima)

This, our third summer in the "half acre," has proved to be the Year of the Orthopterans. We were so excited to hear four (count 'em, FOUR) Field Grasshoppers in the garden our first year. Last year, we found a second grasshopper species. This year, it's off the charts! Not only have we seen literally hundreds of nymphs and adults, we've found a trio of cricket and grasshopper species new for the garden — and one very rare for our county — proof that our little pocket meadow is providing some good habitat. Among our finds is the handsome Speckled Bush-cricket (Leptophyes punctatissima), so named for the myriad tiny black spots that cover its body and long legs. (You may need to click on the above picture to make it large enough to see those spots.) This is one of the more widespread species, reasonably common across central and southern England and coastal Wales. It's found primarily in rough vegetation, including in hedgerows, scrub and gardens, and is particularly fond of Bramble. They're herbivores, feeding on a variety of leaves. Nymphs emerge in May and develop as the summer progresses. (We were seeing mid-sized nymphs by mid-June.) By mid-summer, they're full adults, which breed and survive until the frosts of November. Females lay their eggs in plant stems or under the bark of trees, and these eggs overwinter, with nymphs emerging the following spring. Like all grasshoppers and crickets, males serenade potential mates, rubbing their wings together to make a high-pitched chirp, which is barely audible to most humans — particularly those of us with older ears.

Adult male


Tuesday, 11 August 2020

Soldiers

Common Red Soldier Beetle (Rhagonycha fulva) on Creeping Thistle (Cirsium arvense)
For the last few weeks, it's seemed like most of the flowers in our garden have been covered with mating pairs of Common Red Soldier Beetles (Rhagonycha fulva). From June to August, these slim, bright beetles roam over the flat tops of open flowers, searching for food and potential mates. Umbellifers like Common Hogweed and Cow Parsley, and composites like Common Daisy and Common Ragwort are among their favoured hunting grounds. This distinctive species is common and widespread in fields, meadows and hedgerows across the British Isles. It's easy to identify, thanks to its overall reddish colour and the dark tips to its elytra (the hard wing covers that all beetles have). That bold colour — supposedly reminiscent of military uniforms — is what gives "soldier beetles" their name. It's also the basis for the alternative name "bloodsucker", despite the fact that the beetle is not a bloodsucker, and presents no threat to humans. Outside the UK, Common Red Soldier Beetles are native and widespread across Eurasia, and have been introduced to North America. They're a useful visitor to the garden; adults feed on small insects, such as aphids (as well as nectar and pollen), while the ground-dwelling larvae hunt snails, slugs and other insects.


Friday, 7 August 2020

Wing wavers

Hawthorn Fruit Fly (Anomoia purmunda)
While I was weeding in the garden the other afternoon, my eye was caught by subtle motion on a spike of vegetation nearby. Looking more closely, I found a group of small flies waggling their patterned wings at each other and occasionally engaging in a bit of spirited head-butting, trying hard to shove each other off the leaf. I've never seen a behaviour like it! It's a Hawthorn Fruit Fly (Anomoia purmunda), one of the so-called "picture-winged flies". These little insects measure a mere 4.5 mm (less than 1/4-inch) in length, but their frenzied wing-waving makes them pretty noticeable despite their tiny size. Those wings are distinctively marked too, with a big black splotch near the base and a couple of thinner lines further out. Their eyes, green with two pink stripes, are characteristic as well. Females lay their eggs in hawthorn fruits (though they'll use a variety of other species if hawthorns aren't available). Interestingly, though they were displaying on a shoot of Greater Periwinkle (Vinca major), that isn't one of the known larval host plants. These little flies are reasonably common in the southern half of England and Wales, and from Europe right across the Palearctic to countries bordering the Pacific. Adults are seen between July and October, so we may get the chance to watch them do their wing-waggling/head-butting thing again.

Sunday, 2 August 2020

Spotty one

Orange Ladybird (Halyzia sedecimguttata)
This year has seen an absolute explosion of ladybirds in the garden. The vast majority have been the near-ubiquitous Seven-spot Ladybirds, but a few other species have made an appearance. Last Friday, we added a new one to the list. This eye-catching little beastie is an Orange Ladybird (Halyzia sedecimguttata). Its pale orangey-brown elytra (the hard cases that protect the membraneous wings) are covered with 14–16 creamy-white spots. Like the 22-spot Ladybird I profiled few weeks ago, this one is a mildew specialist. However, unlike that smaller ladybird, which feeds on umbellifer mildews, the Orange Ladybird feeds primarily on mildews that attack trees — especially those that attack sycamores and ash. From April to October, it's widespread in woodland, towns and gardens across England and Wales, but uncommon in Scotland. Beyond the UK, it's found from Europe right across northern Asia to Siberia, northern China and Japan. Apparently, it's attracted to bright lights at night, and is regularly found in moth traps. That's where we found this one, trundling around among the moths. Interestingly, this species used to be associated only with ancient woodland, and was quite rare in Britain. Within the past few decades, however, it made the jump to the mildews of sycamores and ash, and its numbers have increased dramatically. It's nice to learn of a success story, for a change!