Morphos

January 19th, 2012 ChrisR No comments

As a quick follow-up to the “More butterfly wings…” post I thought you might like to see full-sized images of the butterflies used in the tests – starting with the most glamorous ones – the Morpho butterflies. The intense, metallic blue colours on a Morpho are not caused by pigments but instead are iridescence caused by interference generated by the micro-structure of the wing scales.

Incidentally, these specimens were given to me many years ago because they are all damaged beyond commercial value. They hung in a case on my mother’s office wall for many years but when she retired she gave them back to me and they had been in storage until I realised that they’d make ideal subjects to test lenses!

Categories: Entomology Tags: ,

More butterfly wings…

January 13th, 2012 ChrisR 1 comment

I got an unexpected “gift” the other day of a Melles Griot 16x/0.32 160/0.17 microscope objective lens. I had ordered the 10x version (which is probably all I need in terms of magnification) but the eBay seller sent me the wrong one – but, being a nice chap, he said he’d refund me and I could keep the lens because it was just too expensive to send it back – it’s a fairly cheap objective.

Anyway, today I hooked it up to the camera just to see how it performs and I chose the “industry standard” measure – butterfly wings. So here are a few wings at 16x (approximately – I haven’t calculated the exact magnification):

They’re not perfect and I think that I could improve the lighting, but they do look quite impressive in places :)

Christmas in Dorset

December 30th, 2011 ChrisR No comments

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

Butterfly wings

December 6th, 2011 ChrisR 1 comment

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.

Categories: Entomology Tags: ,

Fly genitalia stacks

November 15th, 2011 ChrisR 1 comment

Here are a few stacks of various fly genitalia – taken at 4x magnification using the Schneider Componon 35mm f4 lens.

Some Neotropical Siphonini

November 12th, 2011 ChrisR No comments

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 :)

A stalk-eyed fly (Diopsidae)

November 11th, 2011 ChrisR No comments

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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A few ultra-close shots of tiny tachinids!

November 8th, 2011 ChrisR 2 comments

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.

Some more stacking …

October 25th, 2011 ChrisR 1 comment

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! :D

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 :)

Science Uncovered!

September 26th, 2011 ChrisR No comments

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. :)

Categories: General News Tags:

Swyncombe Down

September 14th, 2011 ChrisR No comments

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 :)

Eggardon Hill

September 2nd, 2011 ChrisR No comments

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.

Beaminster & West Bexington

September 1st, 2011 ChrisR No comments

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.

A great day in Cholsey

August 15th, 2011 ChrisR No comments

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.

Some interesting flies from Paraguay

August 10th, 2011 ChrisR No comments

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.

Categories: Tachinids Tags: , ,

Trichophora (Diaphanomyia) aurifacies, Desvoidy

August 6th, 2011 ChrisR No comments

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

Categories: Tachinids Tags: ,

Jurinia notata, Bigot (Bolivia)

August 6th, 2011 ChrisR No comments

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

Categories: Tachinids Tags: , ,

Archytas aurifrons, Townsend

August 6th, 2011 ChrisR No comments

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:

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

Categories: Tachinids Tags: , ,

Moor Copse & Pamber Forest

June 26th, 2011 ChrisR No comments

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

Categories: Field trips Tags: ,

Scarlet Tigers

June 14th, 2011 ChrisR No comments

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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