Home » 2014 » July

Monthly Archives: July 2014

Isn’t this a … ?

I don’t know if anyone’s heard this story before, but I once uttered the line “Isn’t this a White Prominent?” beside a moth trap in Co. Kerry, which was followed by a great deal of shouting, swearing, hugging, back-slapping and general euphoria. The answer to my question was yes – the first since 1938. I was able to hit the Bucks moth-ers with the line “Isn’t this Oxyptila pilosellae?” on Tuesday night, as I happened to be the first to spot one. It was on the sheet while I was crawling over it pooting beetles, and was the first of three that came to light. With no British record of the Downland Plume O. pilosellae since 1964, Colin Hart wrote that it “may now be extinct” in his 2011 monograph on the plumes. But the Bradenham area in Bucks has produced two singletons in more recent years and now three in one night. Colin himself was there to witness it. The foodplant of the Downland Plume is Mouse-ear Hawkweed Pilosella officinarum, growing on chalk or limestone grassland.

Downland Plume Oxyptila pilosellae at Bradenham by Peter Hall

I focused on beetles rather than moths (though I still saw 8 new moths!) and recorded 33 species, including the whirligig Gyrinus paykulli and the saproxylic species Euglenes oculatus. I had been hoping to see the scarab Odonteus armiger, especially a male with its rhino horn, but it was not to be. This beetle is a familiar sight to the Bucks moth-ers when they’re light-trapping on chalk grassland and seems to be extremely difficult to find by any other means.

More pleasing than any of the beetles was this fly, pooted out of the bottom of one of the traps: the chloropid Camarota curvipennis. Jeremy Richardson and I had been talking about it only the day before, as one of a few curious species of fly that drape their wings around themselves and look like roosting bats. I’ve only recorded it once before but it’s probably common.

Camarota curvipennis with its bat-fold wings.

There’s a really good photo of Camarota here. And also check out this drosophilid which has even more of a roosting bat look to it.

Edible Dormice Glis glis were constantly woofling and squeaking in the adjacent woodland and we could even occasionally see them clambering about by the light of the moth traps. I’d only previously seen them by volunteering for box-checking.

Many thanks to Peter Hall, Martin Albertini, Dave Wilton and Colin Hart for allowing me to join them.

Tales of the unexpected

Jeremy Richardson found a very striking longhorn beetle on Hackney Marsh on Wednesday and identified it as Stictoleptura cordigera, apparently new to Britain. Jeremy emailed me his photos and I was able to offer my agreement with his identification the next morning. I suggested it might make a good day out for Bradley and I on Monday and we arranged to meet up. News came in from Max Barclay at the Natural History Museum that a single S. cordigera had been recorded in “July 2007, collected by Les Wilson on thistles in Hackney Wick”. What had looked like a one-off imported individual at the time, now looks more like the fore-runner of an established population.

Stictoleptura cordigera at Hackney Marsh

Bradley pointed at it and said "Beetle", becoming the fourth person to see S. cordigera in Britain.

I hadn’t given us more than a 50:50 chance of seeing S. cordigera, so I was delighted to lay eyes on it, especially after a long and gruelling journey backpacking Bradley into London on the train. In the end we saw at least four, probably six. But as if that wasn’t enough, the same thistle patch yielded another totally unfamiliar longhorn beetle, which Jeremy instantly recognised as Paracorymbia fulva!

Paracorymbia fulva from Hackney Marsh

Another of Jeremy’s discoveries at this site is the stunning fly Myennis octopunctata. I’d drooled over his photos in Dipterist’s Digest last year so when Jeremy said he could show me some on a nearby stack of poplar logs, I was buzzing. And there they were! In life, they almost seem to be mimicking Salticus jumping-spiders. I had three more ticks on the same pile of logs: the groundbug Rhyparochromus vulgaris, the cranefly Gnophomyia viridipennis and the soldierfly Neopachygaster meromelas, this latter also a new species for Jeremy. This was one of those topsy-turvy places where it seems like everything you look at is a rarity. So much so that I mentioned there’d been a beetle added to the British list in recent years that is a specialist of poplar logs …

And there it was: Hololepta plana out on the surface! An incredibly flat beetle, well-adapted to living under the very tight-fitting bark of poplars.

Hololepta plana from Hackney Marsh

Hololepta plana side on!

Hololepta plana was discovered in the Norfolk Brecks in 2009 and I know it has been seen again in more recent years but I think this is the first occurrence elsewhere in the country. Really nice to find it for myself having dipped it at the original poplar tree in 2009.

Finally, Jeremy showed me the very rare tachinid Litophasia hyalipennis, one of the tiny minority of tachinids that lacks a sub-scutellum. It is officially “Extinct” but has obviously been resurrected!

Many thanks to Jeremy for the guided tour. As I said – he should charge!

A Night at the Achopera

I will be lurking around the Cassiobury Park entrance at ten thirty. I will be able to stay until midnight which should be plenty of time.
Dave.

I had never met Dave Murray of the Watford Coleoptera Group before. He has been working Cassiobury Park and Whippendell Woods for beetles for several years and, as I found out on Friday night, knows the place and its beetles like the back of his hand. After meeting up at the appointed lurking place, Dave took me straight to a lime snag in the Park, I flicked my headtorch on and there was Uloma culinaris!

Uloma culinaris in Cassiobury Park

Uloma is a smart, polished mahogany beetle that the WCG discovered and is still only known from Watford, and from an old record by G.B. Alexander: “Bushy Hall, in rotton wood, 20.vii.1950”. We saw at least six individuals, all on this one trunk, along with a few other saproxylic beetles: loads of Endomychus coccineus (Endomychidae), 1 Triplax aenea, 1 Dacne bipustulata (both Erotylidae) and a few Lesser Stags Dorcus parallelepipedus (Lucanidae). Uloma culinaris is not regarded as a native species, at least not by Alexander et al. (2014). I can’t really disagree, except that it would be nice to think that Uloma has been lurking in the darkness on Watford’s ancient trees since way back, until Dave and co. shone a light on it.

Achopera alternata is another startling discovery by the WCG. It’s an Australian weevil, certainly not native to Britain that was first found at Erddig in Wales by John Bratton (see Beetle News of May 2012). Rowan Alder made an online discovery of a second Welsh locality (apparently photographed somewhere near Llangollen). But the place to see this weevil is Cassiobury Park where Dave and co. have seen it in numbers on some of the stumps. We saw three on exposed sapwood of a beech snag. Even though this is not a small beetle (6 mm), they are quite difficult to spot: cryptically patterned, dull and sloth-like. Through the hand-lens, I watched this one nibbling away at the surface, presumably grazing algae?

Achopera alternata in Cassiobury Park

If you weren’t specifically searching for Achopera, it would be really hard to see, and I wouldn’t mind betting that this beetle is more widespread than we currently know.

Amongst some of the other saproxylic beetles seen on the night were 4 Colydium elongatum (Colydiidae) and a couple of dozen Teredus cylindricus (Bothrideridae), both species that are much easier to see by torchlight.

Many thanks to Dave for the guided tour, and for the humbling insight into what can be achieved by thoroughly working your patch (rather than gallivanting all over the country getting a big pan-species list!).

Reference
Alexander, K.N.A. Dodd, S. and Denton, J. (2014). A review of the scarce and threatened beetles of Great Britain. The darkling beetles and their allies. Aderidae, Anthicidae, Colydiidae, Melandryidae, Meloidae, Mordellidae, Mycetophagidae, Mycteridae, Oedemeridae, Pyrochroidae, Pythidae, Ripiphoridae, Salpingidae, Scraptiidae, Tenebrionidae & Tetratomidae (Tenebrionoidea less Ciidae). Species Status No. 18. Natural England.

Zombie grasshopper

Entomophaga grylli infecting a Field Grasshopper

This grasshopper has climbed to the top of a Wild Carrot stem, then hugged it tight with all six legs and waited to die. Grasshoppers never normally do that but this one was zombified by a fungus: Entomophaga grylli. Once infected, the fungus somehow made it climb and cling before killing it in a nice high spot from which it could disperse its spores. The fungus fruits from between the segments of the insect and in this photo, the fruiting is over and the fungus isn’t very obvious. But the position and pose of the grasshopper is diagnostic. And as far as I know, E. grylli is the only entomophagous fungus that infects British Orthoptera.

I saw this a lot when I was doing my PhD on Chorthippus brunneus so I’m pretty sure this is a common fungus. However, officially there are only 5 British records but I think it is just massively under-recorded: http://www.fieldmycology.net/FRDBI/FRDBIrecord.asp?intGBNum=47709

I still think this is one of the most fascinating biological interactions I’ve ever heard of. How does the fungus get the grasshopper to do that, when it is not even something in the normal behavioural repertoire of grasshoppers? Imagine if there were human infections which could change our behaviour like that …