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The toughest day of 2010: Phratora polaris

24th June 2010: day three of my Scottish fieldwork campaign was to be a change from surveying for saproxylic beetles in woodland. I was headed to the summit plateau of Ruadh-stac Mòr, Beinn Eighe where Mike Morris (1970) discovered the leaf-beetle Phratora polaris new to Britain in 1966. Ruadh-stac Mòr lies within the massive (5,800 hectares) Torridon Forest SSSI.

male Phratora polaris

I had picked a day with a dry forecast but normal weather forecasts don’t apply in the mountains. I set off walking at 07.35 and it started raining 10 minutes later. Within another 40 minutes, I was out of mobile signal for the rest of the day. After a couple of hours of slog, I entered the fearsome Coire Mhic Fhearchair and picked my way across to the steep scree fan in the far corner, passing a few mangled bits of plane wreckage where some poor aviator met his doom. The scree was treacherous underfoot and I was ascending into cloud, with worsening rain and an increasingly strong wind. At the top of the scree, the route steepens into a narrow chute of shattered rocks, exposed and channelling a wicked gusting wind. No place to miss your footing. Step by careful step I got to the top. But there was no relief there – I found myself on a knife-edge ridge in ferocious gusting wind and driving rain. On hands and knees I found a cleft in a boulder and wedged myself half in. Put some dry layers on and decided I’d better abandon the survey and descend. But actually couldn’t face the chute again straight away so I decided to stroll up towards the summit plateau for a bit of respite before beginning my descent. Conditions had worsened further and I was soon reduced to lying full-stretch on the ridge-top path, clinging to the ground and holding my rain-spattered specs on to my face. I realised the ridge had broadened out and I could safely drop off the path to the leeward side, where I could get about in a crouch rather than a crawl.

The chute.

I soon realised I was treading on quality turf: dolomitic limestone grassland with Racomitrium moss, Sibbaldia Sibbaldia procumbens, Dwarf Cudweed Gnaphalium supinum and, more importantly, some patches of Dwarf Willow Salix herbacea, the foodplant of Phratora polaris. I found fragments of a dead Phratora polaris under the first stone I lifted, and a live one under the third stone. Flushed with success I carried out a standard 30-minute timed search but didn’t see any more of the leaf-beetles. All I saw were three Oreostiba tibialis (Staphylinidae), a common species of montane habitats, and one Patrobus septentrionis (Carabidae), found feeding on a pill-beetle Byrrhus fasciatus (Byrrhidae).

Habitat of Phratora polaris.

Phratora polaris was added to the British list (under the former generic name Phyllodecta) by Morris (1970) on the basis of specimens he found near the summit of Ruadh-stac Mòr, Beinn Eighe in 1966 and 1967. Morris (1970) also reported a specimen collected by A.M. Easton near the summit of Tom a’ Chòinich, Inverness-shire in 1968. Owen (1983) added two further sites in 1981: Sgurr Mor and An Teallach, both Wester Ross. Lyszkowski (1988) found the species in 1984 some 60 miles to the south of these sites near the summit of Beinn Achaladair, Argyllshire. Cox (2007) was able to map the species from 9 Scottish 10-km squares of the national grid and commented that the species is “probably under-recorded”. Quite frankly, it’s no wonder!

Once I’d made it down to the bottom of the scree, I found some shelter from the dreadful weather and took a break. Astonishingly, a Mountain Bumblebee Bombus monticola flew past my nook as though it were just a normal summer’s day. I was also filled with respect for the elderly Munro-bagger I passed on my way down – he was heading up in shorts!

Acknowledgement

These observations were made during SSSI condition monitoring work for Scottish Natural Heritage.

References

Cox, M.L. (2007). Atlas of the seed and leaf beetles of Britain and Ireland (Coleoptera: Bruchidae, Chrysomelidae, Megalopodidae and Orsodacnidae). Pisces, Newbury.

Lyszkowski, R.M. (1988). Phyllodecta polaris Schneider (Col., Chrysomelidae) in Argyllshire. Entomologist’s monthly magazine, 124, 71.

Morris, M.G. (1970). Phyllodecta polaris Schneider (Col., Chrysomelidae) new to the British Isles from Wester Ross and Inverness-shire, Scotland. Entomologist’s monthly magazine, 106, 48 – 53.

Owen, J.A. (1983). More about Phyllodecta polaris Schneider (Col., Chrysomelidae) in Britain. Entomologist’s monthly magazine, 119, 191.

Owen, J.A. (1988). A note on the life history of Phyllodecta polaris Schneider (Col.: Chrysomelidae). Entomologist’s record and journal of variation, 100, 91 – 92.

 

When the hunter becomes the hunted

On 21st June 2010 I drove for 10 hours from home to get to Ullapool; the start of an 11-day entomological survey campaign in the west of Scotland. My survey site on 22nd was Rhidorroch Woods SSSI which turned out to be a couple of hours drive on dirt tracks up an increasingly beautiful glen. The weather was superb – a rare treat in NW Scotland – and I couldn’t wait to get into the field.

Rhidorroch Woods SSSI

This isolated veteran pine, above the modern-day treeline, was the best tree I found. Scarred by lightning strikes and ripped by the weight of winter snow, but still living, it was a magnet for saproxylic beetles.

On a fine, sunny day in Scotland, when big beetles like clicks, chafers and longhorns are buzzing past on the wing, there is no better place to be. As long as you’ve got a midge net (and are prepared to abandon all personal dignity and actually wear it)!

Undignified headgear

You also need to keep one hand free for swatting horseflies. And a little time is required each evening for tweezering off all the ticks!

It pretty much goes without saying, but the warning colours of this Bee Beetle Trichius fasciatus (a chafer) failed to frighten me. Very few of these Batesian mimics seem to be good enough at mimicry to fool the human eye.

Bee Beetle Trichius fasciatus

But, as I was investigating the hollow interior of a decaying birch, a bumblebee started harassing me at close quarters. I immediately backed off and legged it away for about 20 metres, reckoning I must have disturbed a nest. As soon as I stopped, I realised it was still buzzing round within a few inches of me. I carry an adrenaline injector with me at all times in case of bee stings: I’ve had a couple of bad allergic reactions in the past. But, even so, getting stung in such a remote spot could be difficult. I legged it back to the birch tree to grab my net, still with the bumblebee in pursuit, and netted it. Safe. Phew!!!

It was only then that I realised it wasn’t a bumblebee! The size, shape, flight and especially the buzzing tone were all spot on and had me completely fooled. But this was a fly, and like nothing I’d seen before. Much later, with help from Dave Gibbs and Andy Grayson I was able to identify it as Cephenemyia auribarbis.

Cephenemyia auribarbis

Cephenemyia auribarbis is a bot-fly (family Oestridae) and it was not looking to bite me or sting me but to lay eggs on me, so that its larvae could develop in either my nostrils, mouth or throat: a truly horrifying prospect! It should have been chasing after Red Deer, the usual host.

Acknowledgement

These observations were made during SSSI condition monitoring work for Scottish Natural Heritage.
 

Christmas shopping entomology

I know for most people a Christmas shopping trip is a lost natural history opportunity. But for a pan-species lister, something good can turn up wherever and whenever. First up, this striking black-and-red Arocatus ?longiceps? bug found on the trunk of a Plane tree while browsing the Christmas market on the Champs Élysées, Paris on 20th November. My French specimen (on the left) looks quite different to the Arocatus longiceps I have previously found on London’s Plane trees (on the right, from the Natural History Museum’s wildlife garden), with paler appendages and reduced black markings on the body.

Arocatus from the Champs Elysees (L) and NHM garden (R)

The following weekend we visited Whipsnade Zoo with friends Rich and Sara and budding mammalogist Lucy. As well as doing some Christmas shopping in the gift shop, we found a couple of interesting insects in the Insect House but on the loose. There were trails of a miniscule ant which I think is a species of dolichoderine but doesn’t seem to be included in Bolton & Collingwood’s RES Handbook, or Skinner & Allen’s Naturalists’ Handbook.

Miniscule ?dolichoderine? ant from Whipsnade

And on the exit door, this Australian Cockroach Periplaneta australasiae was making a bid for freedom. I’ve seen this species before in the Eden Project biomes.

Australian Cockroach Periplaneta australasiae

Finally, our local Tesco in Leighton Buzzard still supports a population of the weevil Otiorhynchus crataegi in the car park, first found here in September 2008. To the best of my knowledge, this is the only Bedfordshire site for this weevil but I’m sure if more people looked it could be found much more widely. It was discovered new to Britain in Berkshire in 1980 and has since been reported from Surrey and Middlesex (map here, doubtless incomplete).

Every little helps (the beetle list)

Entomologising in car park shrubberies can be pretty good. Look out for feeding signs such as notched leaves. Whenever I get out my beating tray and start thwacking the shrubberies, I always imagine I’m going to be either set upon by security guards or ridiculed by crowds of jeering shoppers. But, in practice, everyone studiously ignores me, though I sometimes think mothers take a tighter grip of their children’s hands as they pass! Richard ‘Bugman’ Jones would advise wearing a hi-vis vest in such circumstances: it makes you look so much more official!

Notched leaves on this Euonymus are the first sign that weevils are present.

Otiorhynchus crataegi makes quite regular, semi-circular notches in the edges of the leaves.

Otiorhynchus crataegi: at a supermarket near you?

Happy Christmas shopping everyone!

 

Devil’s-bit Scabious Jewel Beetle Trachys subglaber

March 2016 update: Since writing this post in December 2011, it has become clear that “Trachys troglodytes” actually consisted of two species: Trachys subglaber and the true Trachys troglodytes. This post and the photo above refer to Trachys subglaber. For more info on Trachys, see the jewel beetle page.

While Trachys subglaber may not be quite as jewel-like as some of its larger relatives in family Buprestidae, it is still a little gem. I’ve only started finding it in the last couple of years while surveying calcareous grasslands with a suction-sampler.

Devil’s-bit Scabious Jewel Beetle Trachys subglaber

The best way to record this species, as Keith Alexander has described (Alexander, 1989), is to look for the larval leaf-mines in the host plant: Devil’s-bit Scabious Succisa pratensis. Late summer into early autumn is a good season to be looking, when the Devil’s-bit is in flower. But if you are confident at recognising Devil’s-bit from just the leaves, the leaf-mines can be found from at least 7th June (my earliest record).

Trachys troglodytes mine

Trachys subglaber is not the only species to mine the leaves of Devil’s-bit but the shiny black spot is diagnostic; it marks the spot at which the egg was laid and thus marks the point from which the larva starts feeding to produce its full-depth blotch mine.

Until Keith sussed out the leaf-mines and published his note, Trachys subglaber was regarded as quite a rarity. The current map shows it is widespread in southern Britain, though not nearly as widespread as the distribution of its host-plant! [16.iii.2016: note that I have linked to the map of Trachys troglodytes on the NBN, but this is an error on the NBN – most of these are records or either troglodytes or subglaber and most should be reassigned to T. subglaber]

Reference

Alexander, K.N.A. (1989). Trachys troglodytes Gyllenhal (Coleoptera: Buprestidae) widespread in the Cotswold limestone grasslands of Gloucestershire. British journal of entomology and natural history, 2: 91 – 92. [Browse this article online here].