The Softly Singing Spider

 Cann, A. (2026) The Softly Singing Spider. British Arachnological Society Newsletter, 166, 9.

click for larger image

Carnage in a flower pot

I spotted some strange Hymenopteran goings on on the side of a flower pot on my patio. On investigating, I found this female Common Black Spider Wasp, Anoplius nigerrimus, trying to fly with a large female Common Fox Spider, Alopecosa pulverulenta, considerably heavier than herself up under the rim of the pot. 

The excellent BWARS account for this species makes clear that they aren't too fussy about nesting spots. I interrupted her for a quick portrait, then put her back by the pot with the babyfood (which was done for, having already been paralysed). 

New Arachnid Recording Schemes Atlas

The British Arachnological Society recording schemes atlas has had a long awaited revamp and is now available, with 1.6 million UK Spider, Harvestmen and Pseudoscorpion records to play with. The new atlas is fantastic, with many ways to slice and dice the data. It's taken a huge amount of work to get to this and the team behind it are to be congratulated. It would be fantastic if all recording schemes could make their data available like this.

 

 

Urban Spiders

A new paper shows that Steatoda nobilis and Zygiella x-notata typically made up more than 80% of the urban spiders in an Irish survey. 

Collier, B. L., Leonard, D., Lyons, K., Dunbar, J. P., Lawton, C., & Dugon, M. M. (2026). Survey of Synanthropic Spiders in Ireland Reveals Expansion and Dominance of the Invasive Noble False Widow Steatoda nobilis in Urban Habitats (Araneae: Theridiidae). Ecology and Evolution, 16(3), e73193.

https://doi.org/10.1002/ece3.73193

 

The spiders of Great Britain and Ireland: 2025 checklist

Maintaining a national checklist for a taxon as large as spiders is a monumental task and Alastair Lavery has again updated the UK list, last published in 2019. This update recognises 680 established UK species, an increase of 15 in the last five years. Particularly notable is the number of species in anthropic habitats (buildings) - many of these are surely on the edge, waiting until the climate favours their spread outdoors. Also of interest is the discussion around the yet undescribed spider Megalepthyphantes cf. collinus and Mastigusa where for the first time in a Checklist, I am honoured to be referenced (even if my name is only spelt right once :-)

Lavery, A.H. (2025) The spiders of Great Britain and Ireland: 2025 checklist. Arachnology, 20(3), 410-427.  https://doi.org/10.13156/arac.2024.20.3.8

Good Vibrations?

While I'm yet to catch up with the Wasp Spider, Argiope bruennichi, I have long puzzled over the stabilimentum, a structure produced these spiders to decorate their orb webs. A new study shows that stabilimenta induce negligible delays in prey perception for transverse vibrations and only minor delays for normal and tangential vibrations, primarily due to the added inertial mass. However, for tangential vibrations, the presence of stabilimenta may enhance the spider’s ability to localize prey due to increased connectivity at the center of the orb web. It's an interesting finding but it doesn't eliminate the possibility of other functions, such as making these large webs more visible and so less subject to damage by animals blundering through them. 

Greco G, Dal Poggetto VF, Lenzini L, Castellucci F, Pugno NM (2025) The effect of different structural decoration geometries on vibration propagation in spider orb webs. PLoS One 20(10): e0332593. https://doi.org/10.1371/journal.pone.0332593

 

Spiders of the Rutland Water Lagoons

Palmer, P., Cann, A., Sexton, T., Fox, B., & Pitt-Miller, S. (2025) Spiders of the Rutland Water Lagoons: An Exploratory Survey. ISBN 979-8269245362 Available at: https://www.amazon.co.uk/dp/B0FVMMK466

"This report tells the story of an ambitious survey of invertebrates at Rutland Water nature reserve in England. We used pitfall traps across several lagoons, hoping to focus on spiders but deciding to record everything we caught. Around sixty traps went out. Some were lost to flooding, others raided by crows. Even so, more than a thousand spiders were recovered, along with a by-catch of beetles and other groups. The work was far bigger than we expected. It took time, energy, and patience to bring the results together. Four years later - and with help from many generous volunteers - we are at last ready to share the findings. This report covers only the spider records."

 

Contradictory spider

I recently wrote about microbiome-mediated spread of the Mirid bug Apolygus lucorum. Hot on the heels of that discovery comes another - the microbiome of the invasive Linyphiid spider Mermessus trilobatus does not contribute to its dispersal and spread. 

Complicated, isn't it? 

The Microbiome of an Invasive Spider: Reduced Bacterial Richness, but no Indication of Microbial-Mediated Dispersal Behaviour. (2025) Microbial Ecology, 88(1), 70. https://link.springer.com/article/10.1007/s00248-025-02565-6

 

What's in a name? The Tangled History of the "Charnwood Spider"

Like it or not, we need to start with some history (and taxonomy - sorry). 

Mastigusa diversa - a troubled past   See: https://wsc.nmbe.ch/genus/776/Mastigusa

• The name Cryphoeca arietina was first used by Thorell in 1871, having been previously misidentified as Hahnia pratensis by Menge. 
• This species was then identified as Cryphoeca diversa by Octavius Pickard-Cambridge in 1893. 
• In 1908 Pickard-Cambridge renamed it Cryphoeca recisam.
• In 1913 after wandering around Sherwood Forest, A.R. Jackson renamed it again as Tetrilus recisus (On some new and obscure British spiders. Transactions and Annual Report of the "Nottingham Naturalists' Society" 60: 20-49). 
• In 1937 Eugène Simon renamed it Tetrilus diversus, and in 1953 Locket & Millidge called it Tetrilus macrophthalmus.
• In 1986 Wunderlich changed the genus (again) to Mastigusa macrophthalma, based on taxonomic priority from the species name Tuberta arietina macrophthalma used by Chyzer & Kulczyński in 1897. 
• Which brings us to the taxonomic revision by Castellucci, Luchetti & Scharff in 2024, which suggested that UK specimens were likely to be a new species, Mastigusa diversa. (See: Charnwood Confusion Continues).

Enter DNA. Based on the results of Castellucci et al, my initial hunch was that UK specimens would end up as Mastigusa arietina. But this is Mastigusa we're talking about, and it's not that simple. M. arietina was about to disappear from the UK Checklist, not having been recorded for 100 years (UK specimens having been called ... M. macrophthalma - see above!). Thanks to the Tanyptera Project at the World Museum in Liverpool, DNA barcoding has now been carried out on specimens from across the UK. One of the specimens has in fact turned out to be M. arietina, but most UK specimens are Mastigusa diversa as predicted by Castellucci et al. But what about the Charnwood Spider? The Tanyptera Project says: 

"Mastigusa (Charnwood) - the DNA was sequenced successfully and at a high quality. ... Following these results, the results of your previous Mastigusa, and the papers you provided us, we are confident that this is likely Mastigusa diversa."

You would hope that this DNA-supported moniker now persists. The spider, nor its Spanish cousins ... doesn't care. 

With grateful thanks to Richard Gallon, BAS Spider Recording Scheme, for organizing this work and the Tanyptera Project at the World Museum in Liverpool for carrying out the DNA barcoding and funding it. 

Castellucci, F., Scharff, N., & Luchetti, A. (2023) Molecular systematics and phylogenetics of the spider genus Mastigusa Menge, 1854 (Araneae, Cybaeidae). Molecular Phylogenetics and Evolution, 107833. 

https://www.sciencedirect.com/science/article/pii/S1055790323001331

 

Spider Surprise

A cold December day, half the countryside under water - what else to do but huddle over a nice warm microscope catching up with samples from the summer bulge when it is just impossible to keep up. In this case, a streamside vacuum sample from September. It started off in a humdrum way, knee deep in Bathyphantes gracilis and Tenuiphantes tenuis, but then ... a tiny speck of a spider turned out to be the Ray Spider, Theridiosoma gemmosum. I've never seen this species before and it's the first record for VC55 as well as a considerable range expansion. Fortunately it's a pretty unmistakable species (once you look close enough), which is lucky as this was an immature male - not surprising since September is past the peak for this species. A nice surprise on a winter's afternoon.

Entomology Journal - October 2024

A month of variable weather and troublesome Hymenoptera...

VC55 Terrestrial Heteroptera Recording and Checklist

After a great deal of work - mostly by my colleagues with a shamingly small contribution from me - we were finally able to publish the first two parts of our documentation of VC55 Bug Recording: 

LESOPS 63: VC55 Terrestrial Heteroptera VC55 Terrestrial Heteroptera Part 1: Recorders and Recording. Sue Timms, Kate Nightingale & Alan Cann. Leicestershire & Rutland Entomological Society Occasional Publications Series 63, October 2024. ISSN 095–1019. Available at: https://www.naturespot.org.uk/sites/default/files/2024-10/LESOPS63TerrestrialHeteroptera.pdf

LESOPS 64: VC55 Terrestrial Heteroptera Part 2: Provisional Checklist. Sue Timms, Kate Nightingale & Alan Cann. Leicestershire & Rutland Entomological Society Occasional Publications Series 64, October 2024. ISSN 095–1019 Available at: https://www.naturespot.org.uk/sites/default/files/2024-10/LESOPS64TerrestrialHeteropteraChecklist.pdf 

The plan is for more to follow in future, covering the other major groups. 

My Journal, October 2024

03.x.2024 

Worked on a range of Lygus specimens. I finally feel confident about these tricky bugs (as long as I can find a male!). 

04.x.2024

After the rain of the past week it was good to spend a day out at Melton Country Park. I was surprised to realise that I hadn't actually been there for nine years. I found a very good range of insects the highlights of which were Micronecta scholtzi, lots of Anthocoris limbatus and my favourite ladybird, Hippodamia variegata, the Adonis Ladybird.

05.x.2024

A friend dropped some specimens off for me to identify. The highlight was a male Anyphena numida. This is the first record of this spider for Leicestershire and Rutland. It was first identified in the UK in 2017 and is spreading rapidly from the southeast. 

10.x.2024

After much prevarication I finally cleaned the sensors on the microscope cameras. I don't like doing this because of the risk of damage but it seems to have worked well - far fewer annoying spots in the images now. 

11.x.2024

Quite a good frost, giving me hope for good autumn colour in the days to come took a trip to Cossington Meadows mostly targeting the pools with the dipnet. This produced some good records, including Corixia dentipes.

13.x.2024

Lots of fungi around but I'm very rusty on my ID skills. I'm aware that AI identification divides opinion, but it you think it's going to go away, you've lost the plot. The latest AI incarnation I've become aware of is the beta version of automated picture recognition on the Danish Fungal Atlas website. Seems pretty good to me, with the obvious limitations - https://ajcarthropoda.blogspot.com/2024/10/more-on-unstoppable-rise-of-ai.html

15.x.2024

Took a trip down to Blaby and Countesthorpe. Pond dipping produced a good range of species. 

17.x.2024

Enjoyed a very good LRES meeting at which Ray Morris discussed gall midges, even though galls and Diptera are not my area! Good to have face to face discussions. 

18.x.2024

After a misty start, took a trip to Shady Lane Arboretum on a sunny but windy afternoon before Storm Ashley hits over the weekend. 

21.x.2024

Visited a private estate at Osbaston to do some recording. In the walled garden we found the best growth of Mistletoe that I have ever seen on one of the old apple trees. Even better was the fact that it was only a few feet off the ground. Gently beating this produced a possible single specimen of Anthocoris visci, a Mistletoe-dependent species I have been looking for for two years. Unfortunately this turned out to be a female so we have been unable to confirm the species by dissection. However, a nearby Box hedge also produced Anthocoris butleri, also a good record.  Unfortunately I didn't spot a wasp nest I was standing next to (while trying not to fall in a stream) and managed to get stung on the hand by a wasp, but carried on recording after making a very swift exit, pursued by wasps. 

22.x.2024

Very pleased to have a flying visit from Jon Daws, dropping off some old record material. 

The hand which was stung by the wasp yesterday is now very swollen and painful making it difficult to do anything. I'm becoming increasingly annoyed that I didn't identify the wasp that stung me so that I could record it, and I regard an arm covered in very angry wasps as a rather poor excuse (even though running away as fast as possible was the smart thing to do under the circumstances). 

27.x.2024

Took Jon Daw's tuning fork (in D) to the Botanical Gardens to bother a few spiders in their webs. Moderately successful although there doesn't seem to be that much around at present. 

30.x.2024

A return visit to Osbaston to try to confirm the Anthocoris visci record from a week ago. Sadly we were unsuccessful. 

Read previous Journal entries

  

The return of Enoplognatha latimana

In 2019 I first recorded the spider Enoplognatha latimana in VC55, see: Enoplognatha latimana - a new species of spider for VC55. By 2021 this newly arrived species had spread widely across the two counties but since that time, the advance seems to have slowed down. Despite much tedious checking of Enoplognatha epigynes and palps it's been Enoplognatha ovata all the way. Yesterday I was sweep netting when I turned up several Enoplognatha specimens. Despite the statistics arguing otherwise, some sixth sense told me they were interesting. On checking, one turned out to be Enoplognatha ovata but the other was my first Enoplognatha latimana in a long time. Which was nice. 

 

 

Ozyptila simplex

It's been a couple of years since I've managed to add any new spiders to the VC55 list, so I was very pleased to find a specimen of Ozyptila simplex yesterday. This one looked interesting from the moment I clapped eyes on it so I was pleased when my initial feeling was confirmed. At first sight, the habitat, a dampish meadow with rank vegetation on the banks of the Welland, seems a bit odd for a species normally thought to be associated with sand-hills, coastal grasslands, and estuarine habitats, but it is known to live in inland grassland habitats including fens and reed-beds in Europe. Yet another example of a species on a North Westwards march. 

The Return of Megalegs

 

On 26th January 2022 I was refurbishing a pond in my Leicester garden when I found a single female spider which, after investigation, turned out to be Megalepthyphantes sp. near collinus. Quite a mouthful that (because it still lacks a formal description and naming), so Megalegs for short. This record was a big range expansion for this new spider. And ... that was it. I have not found any more specimens, and neither has anyone else in VC55. Until, that is, Saturday 9th March 2024, when, opening my dustbin I found another female on the inside of the lid. To find one spider may be regarded as fortunate; to find two looks like there is a colony in my garden. The bin was crammed with hedge prunings from the previous day, which is where the spider must have come from. I look forward to future sightings. 

Charnwood Confusion Continues

Folks who have heard me talk about Mastigusa macrophthalma (the "Charnwood Spider") will know that I'm dubious about the identity of this spider, and indeed about the validity of M. macrophthalma as a species. A recent paper takes a close look at Mastigusa from across Europe ... and doesn't solve the problem. The good news is that Mastigusa appears to be a solid genus, dating back 45 million years. I'll let the authors give you the bad news in their own words:

"Morphology-wise, the clade composed by specimens from Southern Spain and the United Kingdom (and the single specimen from the Pyrenees), do not fit with any of the currently described Mastigusa species, showing marked differences with the observed type-material, mostly regarding the morphology of the male palp. Iberian populations have always been considered as M. arietina, while in the United Kingdom both M. arietina and M. macrophthalma have been historically reported, but again only based on eyes characters. The overall morphology and dimensions for these specimens, and their distribution fit with M. arietina, but the male palp consistently shows marked differences with all the other specimens observed. Our molecular data strongly suggests that these specimens could belong to a new, previously overlooked, Mastigusa species."

As a taxonomic lumper I haven't changed my opinion that we're probably dealing with Mastigusa arietina, but something seems to have happened 19 million years ago which shook this genus up. My geology isn't good enough to speculate that that may have been. 

Castellucci, F., Scharff, N., & Luchetti, A. (2023) Molecular systematics and phylogenetics of the spider genus Mastigusa Menge, 1854 (Araneae, Cybaeidae). Molecular Phylogenetics and Evolution, 107833. 

https://www.sciencedirect.com/science/article/pii/S1055790323001331

 

The "truth" about the false widow

 

This paper looks at the origins and spread of Steatoda nobilis, some dodgy arachnology from the Revd. Octavius Pickard-Cambridge, and concludes that the reason for its rapid range expansion is ... unknown (but it's not climate change). 

Steatoda nobilis, a false widow on the rise: a synthesis of past and current distribution trends. (2019) NeoBiota, (42). https://doi.org/10.3897/neobiota.42.31582

Abstract: 

The Noble False Widow, Steatoda nobilis (Thorell, 1875) (Araneae, Theridiidae), is, due to its relatively large size and potential medical importance, one of the most notable invasive spider species worldwide. Probably originating from the Canary Islands and Madeira, the species is well established in Western Europe and large parts of the Mediterranean area and has spread recently into California and South America, while Central European populations were not known until 2011.

We report on long-time observations that reveal that at least two flourishing populations in Germany (Cologne) have been present for over five years, while in Ecuador one population has been observed between 2014 and 2018 and several other records were made in other parts of the country. Data obtained from the British Spider Recording Scheme demonstrate that the species moved significantly northwards since the report of the first populations in the very South of England, after several decades of relative stasis. The sudden northward expansion highly correlates with a massive rise in press coverage of the species.

In the Americas, S. nobilis is currently known from four countries (USA, Chile, Ecuador, Colombia), and available DNA barcoding data obtained for specimens from this area suggest that multiple introductions occurred within each country. Using ecological niche modeling, we identified suitable climate regions for the species and discuss possible reasons for its current spread. We propose that seaside cities and villages with a temperate oceanic or Mediterranean climate are especially favourable potential habitats for S. nobilis and will face the highest colonization pressure in the future, while tropical upland regions with temperate climates are also vulnerable to invasion by S. nobilis.

 

Bionic Spider Silk

High-strength and ultra-tough whole spider silk fibers spun from transgenic silkworms. Matter: 6, 10, P3661-3683, (2023). 

Summary: "To advance ecological civilization, developing sustainable, eco-friendly high-strength and ultra-tough alternatives to non-sustainable synthetic fibers, such as nylon, is crucial. This necessitates a deeply scientific understanding of the fundamental determinants of fiber strength and toughness, as well as overcoming engineering challenges for cost-effective, large-scale production of high-performance silk fibers. Inspired by the mechanical properties of polyamide fibers, including nylon and Kevlar, we employed CRISPR-Cas9-mediated gene editing to successfully synthesize whole polyamide spider silk fibers from transgenic silkworms. These fibers exhibited impressive tensile strength (1,299 MPa) and toughness (319 MJ/m3), surpassing Kevlar’s toughness 6-fold. Thus, they offer promising potential as sustainable alternatives to synthetic commercial fibers. Furthermore, our research provides valuable insights into the fundamental essence of fiber toughness and tensile strength, challenging the conventional notion that these properties are contradictory. These findings have significant implications for guiding the production of synthetic commercial fibers that simultaneously possess high strength and ultra-toughness."

https://doi.org/10.1016/j.matt.2023.08.013

 

The spiderpocalypse is upon us

Arthropod decline at the local (field) scale is largely influenced by changes at the landscape scale. 

"There is widespread evidence for a worldwide trend of insect decline, but we have much fewer data about recent temporal trends in other arthropod groups, including spiders. Spiders can be hypothesised to similarly decline because of trophic dependence on insects and being equally sensitive to local and global environmental changes. Background trends in arthropod populations can be verified if we decouple large-scale environmental transitions, such as climate change, from local factors. To provide a case study on baseline spider community trends, we observed changes in the spider community of an unsprayed alfalfa field and its margin 23 years apart under largely unchanged local conditions. We aimed to determine whether there are changes in spider abundance, species richness and mean species characteristics. Spider abundance per unit effort decreased dramatically, by 45% in alfalfa and by 59% in the margin, but species richness and most characteristics remained unchanged. Community composition in both habitats shifted and became more similar by the current study period. The population decline was especially marked in certain farmland species. We propose that in the absence of local causative factors, spider abundance decline in our study indicates a reduction of spider populations at landscape and regional scales."

Samu, F., Szita, É., Botos, E. et al. Agricultural spider decline: long-term trends under constant management conditions. Sci Rep 13, 2305 (2023) https://doi.org/10.1038/s41598-023-29003-2 

This is why nature reserves don't work: Cooke, R., Mancini, F., Boyd, R. J., Evans, K. L., Shaw, A., Webb, T. J., & Isaac, N. J. (2023). Protected areas support more species than unprotected areas in Great Britain, but lose them equally rapidly. Biological Conservation, 278, 109884: https://doi.org/10.1016/j.biocon.2022.109884

2022 - My Year in Spiders

 I would sum up 2022 as quality over quantity...

I haven't been able to spend as much time as I would have liked on spidering this year, but I'm still pretty pleased with the outcome. The weather has been challenging with alternating exceptional droughts, rainfall and the highest temperature ever recorded here. Although the number of specimens I recorded was well down, I managed to make some nice finds. Here are my highlights.

Megalepthyphantes sp. near collinus

The year started well in January when I was refurbishing an old garden pond into a bog garden and found a specimen of Megalepthyphantes sp. near collinus which I eventually managed to identify with help, a horticultural import I suspect and the first record for VC55.

Leptorhoptrum robustum

This Linyphiid turned up on a streamside survey in March as part of a local river restoration project, one of two projects to which I have devoted field time this year. An inhabitant of the local sewage works, these spiders work their way downstream and I have found them at several places along the watercourse, showing just how much restoration is needed.

Mastigusa macrophthalma

I "refound" the "Charnwood Spider" in VC55 after a gap of twenty years as part the other large landscape project I have been contributing to this year. The first specimens turned up in March at one of the species strongholds, but I was subsequently able to find it at another site where it had never been recorded. More importantly, I was able to confirm that it was not present (following on from decades of arachnological work) at quite a few other sites which look eminently suitable but where it is just absent. I only recently worked out why this is, so I think this quest will be continuing next year.

Textrix denticulata

This attractive spider was a by-product of searching for Mastigusa. This species is not common in VC55, or at least it is not commonly recorded, but I found it at a number of different locations, partial compensation for drawing a blank with Mastigusa on most field trips.

Mangora acalypha

This orb-weaver has only spread to VC55 very recently and the few records have been from a garden so it was a pleasant surprise to find it on Gorse in a rural location. This one is clearly on the move. 

Arctosa leopardus

I found this attractive wolf spider in a riverside sample in May when I was desperately targeting damp places after the spring drought. Much of my time this year has been taken up slogging though hundreds of pitfall trap samples from a large 2021 survey at Rutland Water which turned up several specimens of this species - the first records for VC55. My specimen came from the opposite side of the vice-county, so it is clearly established on different drainages and it is strange that this species has not been recorded before.

Collinsia distincta

This Linyphiid came from the same riverside sample as Arctosa leopardus, making this a productive trip. The first record for VC55 for this species.

Lophomma punctatum

As if two weren't enough, the same sample also produced a specimen of Lophomma punctatum. This spider is well known from the County but not often recorded so it was a nice addition.

Oonops domesticus

Last and very definitely least (size-wise!), Oonops domesticus paid me its triennial visit in October. I only seem to see this spider in my house every three years or so but it is always a welcome sight - one of my favourites. 

 

Old Big-Eyes is Back

 Quiz time! Which species of spider is this the natural habitat of? 

One of them is Textrix denticulata, not particularly common in Leicestershire:

In January I was asked by the Charnwood Forest Landscape Partnership scheme if I could help refind the "Charnwood Spider", Mastigusa macrophthalma. This species was last recorded in Leicestershire 20 years ago, and on Charnwood 21 years ago. Rashly, I said yes, but bearing in mind some good arachnologists have been surveying on Charnwood in recent years, privately I had my doubts. For various reasons, I haven't been able to do much fieldwork yet this year, but recently I was able to revisit one of the last known Charwood sites for the species.

Success :-)

The other interesting thing about this record is that the spider was associating with Formica lemani (thanks to Gavin Gamble and Matt Hamer for the ID) under the rock, which I have not seen listed as a known associate for this species elsewhere:

I'm delighted to have been able to see and photograph this magnificant spider (now back under its home rock after a few photographs). However, I do worry a lot about the amount of disturbance and pressure on the site. My next move, having got my eye in, is to try and find new sites for the species, clinging to its ancient Charnwood home by its teeny tiny claws.