ChrisR

Here are some photos from the Dipterist’s Forum Spring field meeting to Denny Wood in the New Forest.

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The parcel...

This week has been a good one for deliveries – today I received a parcel from my friend Yves. This is part of a batch from Nouragues, French Guiana, collected by Stephane Brule a few years ago.

My first impressions are that the material has a lot of dead leaves and it seems to have come from a “window trap”, which is good for beetles but not for flies. Yves says that he got some good wasps out of it.

... and what was inside!

EDIT (2/3/2012): I have had a look at one of the bottles of material and it was very disappointing – just a mixture of leaves, broken beetles, broken cockroaches, a few ants and some calliphorids, like Mesembrinella. I would have tried to make something out of the mess by salvaging the Mesembrinella but on closer inspection I saw that most of them are missing all of their bristles and quite a few legs and antennae … so not worth the hassle. The samples are going to be topped-up with alcohol and then put into storage in the garage in case I find anyone that wants to have a look at them!!

This is a close-up shot of a typical Nouragues sample – a 2cm thick soup of insect bits and leaves

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This week I have been working on a batch of Venezuelan tachinids, kindly sent to me by Manuel Ayala (see right). They are a lovely mixture of species collected my Manuel since the 1960s – all hand netted so they are in quite a good condition.

The highlights of the batch are definitely the male & female Bibiomima handlirschi, a very widespread neotropical tachinid but very rare in collections. See here for a photo of the one in the NHM collection.

Identification of material like this is tricky but I am using Monty Wood’s keys in the Manual of Central American Diptera (volume 2), which are a good basis for work in other neotropical regions but you do have to remember that the name that you reach in the key (at best) should be taken as a potential close relative of your specimen.

The list of name so far reads: Beskia aelops, Bibiomima handlirschi, Belvosia, Quadratosoma, Hystricia, Anepalpus, Bombyliomyia, Jurinella, Epalpus, Parepalpus, Lindigepalpus, Archytas, Cylindromyia, Macromya, Trichopoda, Acaulona, Telothyria, something close to Neosophia, some things close to Calolydella, a Goniini, Winthemia and Chrysoexorista.

I will try to do some close-up photos later

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Have just come back from a lovely, relaxing trip to my parent’s for Christmas … lots of chatting, eating and (a little) drinking, all in the beautiful surroundings of deepest Dorset. Mum treated us to a massive array of delicious food and we all pitched in as much as possible. Then when it wasn’t raining we’d take a walk on the local beaches, to beachcomb and look for interesting shells & seeweeds.

* photos of seaweeds & shells to come later

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One of the standard ways to test a macro photography set-up is to photograph a butterfly’s wing and then show the image as a crop at the maximum digital zoom. Here are a few photos taken with my EL-Nikkor 50mm f2.8 lens reversed on bellows to give 3:1 magnification on the sensor:

These photographs have just been lightly PhotoShopped (levels, brightness, Smart Sharpen) and then cropped at the maximum level of detail.

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Today I went through some of the specimens in my World collection that had been labelled under the siphonine genera (Actia, Borgmeiermyia, Ceromya, Pseudosiphona etc.). Here are some photos:

The Erythomelana is only “possibly” at the moment … it keys to that but I have never seen the genus so I have asked Monty Wood to see what he thinks. Erythromelana isn’t actually a siphonine anyway – it just looks a little like one

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Here is a stalk-eyed fly from Western Malaysia, taken at about 3x magnification. The equipment was Canon 1000D + Schneider Componon 35mm f4 lens reversed on bellows racked to 50mm. This is a 19-photo stack processed in Zerene Stacker (PMax method) and then in PhotoShop.

The eyes on this fly are about 4mm apart and almost filled the frame in the photos.

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It’s not often that you get this close to the very rare and tiny Microsoma exiguum (3mm), Cinochira atra (2mm) & Catharosia pygmaea (4-5mm). I have been playing around with a Schneider Componon 35mm f4 lens – a new acquisition from eBay for £16 posted. When reversed on bellows and racked out to about 90mm it generates about 4:1 magnification – that’s 4x life size, on the sensor!

The most difficult part is to move the camera in small enough steps that no parts are left unfocused … at magnifications above 2x it gets very difficult indeed. The illumination was made using an old SunPak ring-flash on the left and holding a YN560 above and in front of the specimen – the specimen sits in a polystyrene cup, which acts as both a diffuser and reflector, with a piece of grey card stuck to the back to act as a background.

The stacking has been done using Zerene Stacker – mostly the PMax method but one using DMap … the DMap method tends to produce nicer stacks when it works but it is very hard to configure it to work when the specimen has a lot of bristles.

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Here are a few Pelecotheca (Cryptocladocera) sp. stacks. The technique involves taking about 30 photos, each at a different focal point in the specimen and using a macro-rail to slowly move the camera backwards or forwards. The focused parts of each photo are then combined using software called Zerene Stacker (Pmax setting) to make the final image, which looks as though it has an incredibly deep depth of focus – something that would be impossible with normal photography.

The photos were taken using a refurbished 10 megapixel Canon 1000D; Nikkor EL 50mm f2.8 lens reversed on cheap bellows; Yongnuo YN560 flash offset to the right and run on half power. The specimen is enclosed inside a polystyrene cup and the lens has a cardboard lens hood to reduce flare. The photos have been taken at approximately 1.5x life-size on the sensor. This technique and equipment has been used under the guidance of several members on the excellent photomacrography.net forum!

This fly is the male of the species and it can be assumed that the many-branched, hairy (multifissicorn) antennae must be used to locate the females but little is known of their ecology and even the hosts are unknown. They seem to occur throughout northern South America (the Guianas, Brazil & Peru) and belong to a tribe called the Neominthoini, which includes many genera of flies with strong bristles on the facial ridges and quite distinctive genitalia.

These are 3 shots of an Oestrophasia sp. from Brazil – the exposure is slightly off but getting the lighting correct is always the biggest problem in stacking. PhotoShop has made them look passable at least.

A Prosena siberita, showing the plumose arista and long proboscis:

Prosena siberita (1920x1080p) at 1.5x on the sensor

Here are a few shots of the latest stacking setup:

Everything sits on a sticky, yellow, rubber mat that people use to hold rugs down on laminate flooring … the specimen is pinned inside a polystyrene cup which acts as both a diffuser for the flash and reflector which bounces the light around from all directions onto the specimen. A black paper tube has been wrapped around the lens to act as a long lens hood to reduce flare. The rail is hand-cranked in the smallest increments that I can manage with my clumsy fingers and the camera is triggered using a cheap remote shutter release. The JPG images are downloaded immediately onto a PC using the free Canon EOS Utility software and then post-processed in Zerene and PhotoShop

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Last Friday I had the pleasure of helping out at the Natural History Museum’s yearly “Science Uncovered” event. For one evening the museum opens its doors until late into the night and scientists that normally work behind the scenes come out to show the public what their work is all about.

On our stand (“Taxonomy 2.0″) Vlad & some of the IT guys were showing off the latest versions of “Scratchpads“, the NHM’s website toolkit for taxonomists. Scratchpads gives taxonomists a framework for creating websites where they can publish information about their research and to collaborate with other taxonomists.

We were also showing the latest SatScan scanner with some of the guys from Smartdrive. The system captures very high-resolution images of museum specimens – usually in museum drawers. A camera moves across the drawer taking small pictures which are later stitched together into a 500MB, 20,000 x 20,000 pixel image. This image can be stored in a permanent catalogue of the museum’s collections and, more importantly, the image of each individual specimen can be cropped out and stored along with metadata that would enable researchers to search for them in the museum’s specimen database. Eventually it is expected that the images will all be made available online – allowing researchers living abroad to search the museum’s reference collections and do basic research without travelling thousands of miles to visit the museum.

I have been helping Vlad to specify and develop the software that grabs the images and that collects metadata associated with each specimen image. It was really good fun to chat to the visitors and to see their enthusiasm for the work we are all doing.

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Just a few photos from a quick “recon” visit to Swyncombe Down with Rod d’Ayala, ahead of our guided walk for the Reading & District Nat.Hist.Soc. on Sunday 18th (14:00). The weather was lovely and luckily I bumped into a very interesting chap who was there to repair some horse jumps ahead of their cross-country event. Anyway, while chatting he mentioned a colony of rare snails … big ones … grey shells. Turned out to be a colony of Roman Snail – a very rare species in the UK and this could even be a new site for them!

Interestingly, we also saw lots of plants in flower that traditionally only flower in Spring – such as Chalk Milkwort. I feel this must be due in part to the cold summer and the early ‘finish’ to the summer species – combined with the shortened day-length the plants obviously feel as though it is Spring!

Also seen on the day were: Abida secale (a rare snail of chalk downland), Meadow Brown, Red Admiral, Small Copper, Aplomya confinis (a parasitoid of blue butterflies), Tachina fera, Phania funesta. Atypus affinis (the Purse-web Spider) was also found on a short-cropped, sunny bank. Red Kites were above us for the whole visit and often soaring below us as they quarter the arable fields for food which was fascinating to watch. A pair of Hobby and a Sparrowhawk also flew over as we walked.

All in all a very interesting site to visit – even late in the season

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Eggardon Hill is an ancient hill-fort, owned by the National Trust, south of Powerstock Common on the back-road from Beaminster to Bridport. Besides having the best views in the county it is an excellent place to see butterflies and downland flora & fauna.

We saw Wall Brown in good numbers, along with lots of Small Tortoishells, Small Heaths and some Common Blues and Meadow Browns. But the star of the day was spotted by my mum – Autumn Lady’s-tresses (Spiranthes spiralis) growing on a 50m stretch of the banks just by the entrance gate.

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The day started well when I saw a lovely Gold-ringed Dragonfly in the garden in Beaminster. They are a very rare species away from their normal haunts (Scotland, Wales & the West Country) and I had never seen one before.

Later, at West Bexington, we managed to chalk-up quite a list of butterflies (Small Tortoishell, Red Admiral, Common Blues, Brown Argus, Small White, Small Heath, Meadow Brown) and saw lots of Long-winged Coneheads of all sizes.

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Tony’s meadow in Cholsey has been a survey site for the Hornet Robberfly (Asilus crabroniformis) because it is the center of a thriving population and he has been monitoring them himself for many years.

Today I went over there with my friend Carim, who had traveled out from London specially to see Asilus. The weather was a bit overcast but there were still plenty of Asilus in the meadow (Tony saw 27 on a transect) and I photographed quite a few tachinids on the Wild Carrot.

The rest of the flies are all tachinids – mostly fairly common summer species but it was nice to find Bithia spreta in Tony’s meadow for the third successive year.

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Today I received a small parcel of Diptera from Ulf in Paraguay – many thanks Ulf!  In the mix were lots of different families but he had sorted out mainly the calyptrates for me … with an emphasis on the tachinids, of course.

Here are the first specimens from the parcel – 2 Tachinini that illustrate the principle of never leaping to snap judgements. Although they look like they could be the same species they are actually completely different genera – one has long palpi and the other has no palpi at all … so they diverge quite early in Monty Wood’s key. Of course Paraguay is a long way from Central America so it is a big stretch to assume that they can be identified in the key but it will at least show a level of relatedness.

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In this post I showed a species of Trichophora determined by Monty Wood. During a visit to the BMNH I discovered that there were no similar Trichophora spp. in their collection but in the same drawer I found Diaphanomyia aurifacies, which seems a very good fit … and this is obviously closely related to Trichophora.

I have just heard back from Monty who has confirmed that he considers Diaphanomyia to be a Townsend synonym of Trichophora so I have adjusted my posts accordingly.

* specimen photos used courtesy of the BMNH curators

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In this post I showed a Jurinia sp. from Bolivia, determined by Monty Wood. During a visit to the BMNH I discovered a species called Jurinia notata, Bigot (holotype in the collection). Here are some photos of the BMNH material, including the holotype (sadly not in good condition) and an additional specimen.

* specimen photos used courtesy of the BMNH curators

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Last week I spent a happy afternoon at the BMNH, courtesy of Erica & Nigel in the Diptera department. I decided to concentrate on a few genera and try to identify a few neotropical specimens. My first was Archytas, a large genus with many very similar species, because I have a few quite atypical taxa in my collection.

Normal Archytas are usually medium/large flies with a black body and a dusted thorax with a slight bloom/cast on T1-4. But my atypical ones are smaller and more glossy with orange abdominal side-patches, so I thought that they might be a good candidate to track down. After a few drawers I found just what I wanted – a block of 3 species that looked similar to mine. Archytas aurifrons was by far the commonest, with many specimens from Brazil, and it fitted mine better because the frons has golden dusting, while the other species seem either less dusted or with white/silver dusting. But, to be honest, the others (inambaricus & dissimilis – ironically very similar!) seem to have a lot of overlapping morphology and the chances of working out why they were split are minimal because the original authors are unlikely to have described them very well!

My specimens are pictured here:

• Archytas aurifrons from Brazil
• Archytas aurifrons from French Guiana
• Archytas aurifrons from Peru

Below are some photos of the BMNH’s specimens – used courtesy of the BMNH curators:

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Today was an absolutely glorious 28C and sunny (without a gale-force wind!) so I headed out for Moor Copse to see what I could find.

I set off along the river bank accompanied by a chorus of 100s of Roesel’s Bush-cricket coming from the long grass. I soon saw Ringlets, Meadow Browns, Scarlet Tiger (sitting on foliage) and my first Silver-washed Fritillary … plus (on the hogweeds) Cheilosia illustrata, Nowickia ferox & Gasteruption jaculator. The Silver-washed Fritillaries were almost the commonest butterfly on the walk – probably only eclipsed by Meadow Browns, but only by a little. Other things seen were Speckled Wood, Small White, Small Copper, Marbled White, Red Admiral, Small Tortoishell & a solitary and very fresh Six-spot Burnet moth. On the tachinid front it was a bit quiet but I did see Thelaira nigripes, Phasia pusilla/barbifrons and Dinera grisescens. There were also quite a few sarcophagids and anonymous-looking tachinids too but these will have to wait to be examined more carefully before I can give them a name.

Rather than go home for lunch I decided to push-on and visit Pamber Forest where I had seen a suspected Gymnosoma a few years ago. Sadly there were no Gymnosoma today but the forest was full of Silver-washed Fritillaries – they were everywhere and all in perfect condition. It was here that I managed to get a few videos of the Fritillaries nectaring on bramble flowers.

Silver-washed Fritillary #1

Silver-washed Fritillary #2

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The Scarlet Tiger is a very local species of moth, found mainly in the southern England. Normally I find them on Moor Copse, a nearby nature reserve with a small river running through it, but occasionally they do roam further afield (or perhaps get blown?) and this year I have seen one twice in my back garden in Tilehurst. My neighbour was so surprised that he rushed out and took photos of it when it landed next to his pond

The larvae feed on Comfrey, Nettles & Brambles and the adults are highly aposomatic (having warning colours to deter predators).

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