One (OM) Lens to Rule Them All

The Olympus M.Zuiko Digital ED 75-300mm f/4.8-6.7 gets looked down on by Olympus snobs because it's "not as sharp" as some of the much heavier OM Pro lenses. I've just picked up an excellent used copy of one of these compact, light, cheap (everythng is relative!) lenses. So what do I think? 

For just over 200 quid I've got a 600mm full-frame equivalent lens which is capable of photographing a bird at the top of a tree, or by sticking a Raynox DCR250 lens on the front, making a focus stack at 1.5X magnification. 

But is it sharp enough? I'll let you decide:

 

The Kleidocerys Conundrum - Resolved?

I've been bothered about Kleidocerys for a while - specifically, is Kleidocerys ericae a separate species from the familiar Birch Catkin Bug, Kleidocerys resedae? See: The Kleidocerys Conundrum. When I cogitated about this two years ago it was obvious that DNA was the way out of the mess. A recent paper spurred me into action - time to find an answer. 

In a nutshell, DNA barcoding is a method of identifying species by sequencing a short, conserved region of DNA. The ideal DNA barcode gene needs to have enough variation between species to tell them apart, but be conserved enough within a species so it can be easily identified. The 5' portion of mitochondrial cytochrome c oxidase subunit I (COI-5P) has become the standard Arthropod barcoding marker. A vast amount of DNA barcode data has now accumulated. At the time of writing, the International Barcode of Life (iBOL) initiative - www.boldsystems.org - has examined 26 million specimens, 21 million of them from Arthropods. Helpfully, the BOLD website makes it (relatively) easy to examine them, so I plunged into looking at the Kleidocerys data. 

CAVEAT: It's been a while since I did this professionally, and even then, it wasn't really my specialism. What follows is my interpretation. Others reading this may well know far more about it than I do, in which case, please let me know. 

A DNA dendrogram - tree diagram (if it was good enough for Darwin to sketch in his notebook, it's good enough for me) - is a visual representation of the genetic relationships between different organisms, or in this case, DNA sequences. Here's the tree for the Kleidocerys COI-5P barcodes:

(click for larger image)

In summary:

• Kleidocerys resedae and K. ericae each form sequence clusters with similar levels of relatedness. This supports the idea that they are indeed separate species.
• Kleidocerys privignus, very similar in appearance to K. resedae but which is said to occur on Alder, also appears to to be a separate species. (NB: one privignus sequence clusters within the resedae sequences (blue arrow) - presumably a misidentified specimen). 

So what does it mean for me? That I probably need to keep looking for K. ericae, although it is possible that it may not occur in VC55. It also means that I should probably look for K. privignus - time to target the Alders this year. 

Has this made my life simpler? Nope. When did technology ever do that?

 

DNA Barcoding - where are we, and why should I care?

"Most insects encountered in the field are initially entomological dark matter in that they cannot be identified to species while alive." The DNA revolution in entomology has been progressing diligently in the background but not making much of a splash with civilians. A new paper provides a good overview of the state of the art and makes a prediction: the big leap happens when DNA and AI start working together. 

Illuminating entomological dark matter with DNA barcodes in an era of insect decline, deep learning, and genomics. (2024) Annual Review of Entomology, 70: 185-204 https://doi.org/10.1146/annurev-ento-040124-014001

Abstract: 

Most insects encountered in the field are initially entomological dark matter in that they cannot be identified to species while alive. This explains the enduring quest for efficient ways to identify collected specimens. Morphological tools came first but are now routinely replaced or complemented with DNA barcodes. Initially too expensive for widespread use, these barcodes have since evolved into powerful tools for specimen identification and sorting, given that the evolution of sequencing approaches has dramatically reduced the cost of barcodes, thus enabling decentralized deployment across the planet. In this article, we review how DNA barcodes have become a key tool for accelerating biodiversity discovery and analyzing insect communities through both megabarcoding and metabarcoding in an era of insect decline. We predict that DNA barcodes will be particularly important for assembling image training sets for deep learning algorithms, global biodiversity genomics, and functional analysis of insect communities.

This set me thinking .. (contd)

 

Entomology Update - January 2025

Only a limited amount of entomology from me this month - the weather not helping - but lots of updates. 

Ants - Naturalists Handbook

Should I buy more books? :-)

What *another* camera? Part 2: All out on OM

This is a long and detailed post about photography (macrophotography specifically), you can skip this if you're not interested.  Also nerdy: In Praise of the Flying Nun.

Diptera for the Desperate

An unexpected find in the garden.

Parasitic Pink Pom Poms

You might think day-glo pink fungi would be hard to overlook, but this one isn't often recorded. 

UPF - Ultra Processed fertilizer

A new research paper helps to explain the lack of biodiversity in hige swathes of VC55. 

It's not the dogs fault

Since the pandemic the number of dogs has exploded, and with that, the amount of environmental harm being caused. II don't blame the dogs for this... 

Finally some good news

2025 begins on a bright note with new life breathed into the UK Springtail Recording Scheme. 

If you'd like to see *lots* more photos, I post then regularly on my Bluesky account: https://bsky.app/profile/ajcann.bsky.social

 

 

 

It's not the dogs fault

Since the pandemic the number of dogs has exploded, and with that, the amount of environmental harm being caused. I've seen so much habitat degradation over the last few years, associated with much heavier traffic than years ago. I don't blame the dogs for this. Working from home also plays a large part... The question is, what are we going to do about it? 

Unleashed: walking dogs off the lead greatly increases habitat disturbance in UK lowland heathlands.  (2024) Urban Ecosystems, 1-10.  https://link.springer.com/article/10.1007/s11252-024-01568-4

Abstract: Human population growth is associated with increased disturbance to wildlife. This effect is particularly acute in urban and periurban areas, where the area of effective disturbance extends beyond that of human presence by the roaming behaviour of pet dogs. Dogs are globally the dominant companion animal, with a population of ~12 million in the UK. As urban areas extend, dogs are exercised in green space close to housing. In southeast and southern England these areas include lowland heath, a habitat of high conservation value. To quantify disturbance caused by dog walkers and their dogs, we used GPS units to track the movement of people and their dogs across four lowland heath sites, used a questionnaire to ask about dog walking habits, and mapped potential areas of disturbance caused by dog walkers. Questionnaires were completed by 798 dog walkers and the walks of 162 owners and their 185 dogs were recorded. Mean (±SE) walk time was 56 ± 23 min, walk distance 3.75±1.68 km and dogs were a median distance of 20 m from the owner during walks. Dogs were walked once (44%) or twice (56%) a day. Most (always: 85%; always or occasionally: 95%) dogs were walked off the lead even when signs were present requesting that dogs were kept on a lead. This resulted in up to a 21% increase in reserve area disturbed. In one reserve (Snelsmore Common), >90% of the area was disturbed by dogs, greatly eroding its conservation value. This work highlights the importance of considering how dog ownership can exacerbate levels of disturbance in sensitive periurban habitats when housing developments are planned.

 

There's useful information on Managing visitors with dogs in your woodland from WWW.GOV.UK here.

 

UPF - Ultra Processed fertilizer

A new research paper shows a large and significant negative effect of the major plant nutrients (NPK) on the abundance, species richness and functional diversity of both pollinators and flowering plants. Even average use of nitrogen fertilisers cut flower numbers fivefold and halved pollinating insects. This isn't a novel finding but the data presented is incontrovertible. This helps to explain the lack of biodiversity in huge swathes of VC55. 

Trade-off between pollinator-wildflower diversity & grassland yields. npj Biodiversity volume 4, Article number: 1 (2025) https://doi.org/10.1038/s44185-024-00070-6

In Praise of the Flying Nun

Macro photography has been hugely improved by the development of "flying nun" flash diffusers (such as Cygnustech diffuser, AK, MK, etc - good comparison here: https://wildmacro.de/the-best-flash-diffusers-for-macro-photography/). The closeness of the flash to the subject causes hot spots and burnt out highlights, and shiny subjects such as beetles are particularly difficult. The curved diffusion surface helps to solve these issues. 

 

Photography Equipment

I get asked this question, so for the record, my photos are currently taken using:

• Macro photos taken using OM System OM-5, M.Zuiko Digital ED 60mm F2.8 Macro lens, +/- Raynox DCR-250/DCR150, Godox V860IIIO flash, Cygnustech diffuser.
• Field Photographs (2023 on) taken using an Olympus TG-6 with the Olympus TG Light Guide. 

More details here. 

Previously:

• Sony a6500, Sony FE 90mm F2.8 Macro G OSS +/- Raynox DCR-250, Godox V860IIIS flash, Cygnustech diffuser.

Microscopy:

• Microscope photos taken using a Sony a7Rii on a GXM UltraZoom-3 trinocular stereo zoom microscope. (Prior to 2022, I used a GXM XTL3T101 microscope.)
• Higher magnifications using a Sony a6000 on an Apex Practitioner compound microscope.
• Images stacked where necessary with Helicon Focus.

One very important caveat:

 

If you went to a Michelin-starred restaurant and ate the most delicious meal of your life, would you ask the chef ,"What oven do you use"?

 

Parasitic Pink Pom Poms

 

On a recent outing Arthropods were very hard to find, but while searching I spotted some pink dots on a lichen-covered twig. It was one of those occasions when I knew exactly what it was, the lichenicolous fungus (a fungus which is a parasite on lichens) Illosporiopsis christiansenii. You might think day-glo pink fungi would be hard to overlook, but sizeism kicks in and they are usually overlooked because of their small size. I've been looking for this species and while it's not rare I've not seen it before. There are a couple of species it could be confused with so to confirm I checked the characteristic coiled spores under the microscope.