Dipterists Forum Weekend at FSC Preston Montford

Fantastic content, course leaders, inspiring dipterists and great food were just a few of the pros of attending the Dipterists Forum Weekend on the 16th-19th February 2018. So why did I decide to attend this course? 1) flies are awesome and 2) Anthomyiids are quite intimidating to identify morphologically and I need to be able to do this for my PhD. For some reason, I always seem to choose to study groups that have other entomologists wishing me good luck. When I first started to get into aphids, many Hemipterists said ‘well, good luck with that!’ and when I introduced the topic of my PhD to some Dipterists I received the same reply… So, I was hoping that the fantastical dipterists of the dipterists forum, with their greater experience and knowledge, would help me with becoming more confident in Anthomyiidae identification. I can confidently say, they did!

Despite the traffic on the way down, we still managed to arrive in time for dinner Friday night. After dinner, the evening kicked off with Phil Brighton and Martin Harvey giving overviews of the two fly families we would be covering this weekend, the Anthomyiidae and Soldierflies and allies. It has to be said that the only thing that could get me into a classroom on a Friday evening would be insects, particularly these fascinating flies. Phil started by discussing some of the species found within the Anthomyiidae, and I started getting quite excited every time that Pegomya were mentioned. Martin then took over to talk about a few things in respect to some of the material that would be useful to look at Soldierflies and allies, including the fantastic Stubbs and Drake book (that I am now a proud owner of thanks to Alex!).

 

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The Dipterists Forum Anthomyiidae Key!

I started off my Saturday morning looking at some of the male anthomyiids that Howard Bentley kindly brought along to help with the course. Although a sometimes-challenging group, Howard produced a lovely key to the 25 most common species which I found extremely helpful in determining the species I was working with. Admittedly, it’s been a while since I identified flies, but the key came with some incredible diagrams and drawings of some of the key features which were produced by Michael Ackland (Anthomyiid god) which helped me a lot! With the help of the test keys, I managed to successfully identify quite a few male flies, with just a few bumps along the way. But I no longer think that anthomyiids are completely impossible to identify, which was the point of the weekend! Sunday morning, I then thought it was a good decision to try identifying some of the females since I’ll probably be doing some work on them for my PhD. The females were harder to identify, and I struggled more with these than the males. However, I haven’t given up! I’ll keep working on the females when I can, because I think it would be fantastic to be able to identify them, but also because I simply refuse to admit defeat. And I suspect that once I’ve gotten the hang of them (with a lot of practice), they won’t be as hard to identify as I feel that they are now.

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Hylemya variata from Howard Bentleys collection (Photo by Alex)

It was also lovely finally putting names to faces. I’ve heard and seen (on fb and twitter) the names of a few of the dipterists who attended this year. I was happy to finally meet Nigel Jones, an entomologist from Shropshire, who I never had the chance to meet during my time at Harper Adams. Nigel happened to have collected Pegomya betae (identified during the course of the weekend) and was very happy to show me some of the fantastic pictures he’d taken of the fly’s characteristics. I was very, very excited about this. And Nigel has kindly let me have access to these photos for use during my PhD (thanks Nigel!).

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Lateral picture of the Surstyli of Pegomya betae (Photo by Nigel Jones)

I don’t think most people can say that they have the pleasure to know anyone who are so passionate about something that even after dinner, they preferred to stay in the lab (some of them until 10pm onwards) looking at flies, rather than going to the bar. It was inspiring and I am still very much feeling the hype of the weekend. I’ll look forward to working more with anthomyiids in the future and will definitely be doing some anthomyiid recording in the coming years! 🙂

 

Now, over to Alex!

 

Shortly after Howards whistle-stop tour of the Anthomyiid test key, the lights dim and the second session begins. Representing the Soldierflies and Allies recording scheme, Martin Harvey takes centre stage. Martin began by stating that though he had not brought a new key to the event (he cites the previously mentioned Stubbs and Drake book as akin to the bible, and he’s right, it really is incomparable), he had brought some supplementary material to aid in the identification of some of the more complicated taxa. He also took the time to run through the current status of the recording scheme, showed us how the records are used and how the current atlases were looking. With the digital age making specimen identification and recording accessible by the touch of a screen, I urge everyone to get out there recording as many soldierflies as possible this year (and be sure to follow the recording scheme on Twitter, @SoldierfliesRS (other insect recording schemes also available)), and at this time of year to be vigilant for the arrival of the first common beeflies of the year, Bombylius major. Prize to the first person to record one this year (disclaimer – there may not be a prize and I take no responsibility for anyone being misled by this statement)!

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Beris vallata – Identified from Alex’s own collection

Handouts for this session included notes on the Stubbs & Drake keys, providing notes on some of the more ambiguous couplets, a translated version of Morten Falck’s key to the Norwegian Therevidae (notorious amongst Dipterists for being a particularly difficult family), localised for British species and various materials on the horseflies (Tabanidae) – including two keys to Hybomitra and Haematopota utilising some wonderful stacked photographs of specimens from the Natural History Museum’s collected, compiled by Harvey for the event. There was even a couple of *classic* Tabanidae books, brought along from the BENHS and Liverpool World Museum collections for people to peruse as they pleased – a rare treat indeed!

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Haematopota pluvialis (m) – Identified from Alex’s own collection

Specimens were on offer from the NHM and Liverpool World Museum collections, and featured a selection of rare or particularly special species found across the UK. I brought along a box of my own specimens, in order to work through some of my unidentified material in the company of those who would be able to tell me whether or not the specimen I had identified was indeed the incredibly rare dune-dwelling species that is known from only one record in 1842 making me the first person to find one in over 150 years, or whether it was in fact the most common species in the country. I had brought along with me a ­Hybomitra I had caught in Staffordshire the previous summer. Due to the genus being a tricky one, the Stubbs & Drake key had repeatedly lead me to label it as H. solstitialis, a rather rare and endangered scarce species. However, utilising both the key and Martin’s stacked photography, I settled upon H. distinguenda as the likely culprit. Perhaps not as amazing as a solstitialis finding, but satisfying to have finally identified the specimen. Martin and I also became briefly puzzled by a Thereva specimen, believing it initially to be T. strigata, a species known in the UK from only a single record, but reigned ourselves back in to identify the specimen as the much more common (but no less cute) T. nobilitata.

I also spent a fair bit of time looking at some specimens from the museum collections, attempting to observe the differences between the bee flies Bombylius minor and canescens, looking at some of the impressive, large soldierflies such as Stratiomys potamida (a species that Martin joked about ‘having never seen, yet friends have found specimens at the end of my road!’, and one I’ll definitely be on the lookout for this summer) and looking at some of the truly bizarre but amazing Acroceridae. The species pictured below is Ogcodes gibbosus. Frankenstein’s miniature monster, it is not. Tiny-headed, humpback, spider-killing fly it most certainly is.   

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Ogcodes gibbosus from the Natural History Museum Collections (photo by Alex)

I would just like to thank everyone at the Dipterists Forum who came to the course at FSC Preston Montford. Lots of people have been really supportive and offered lots of help with furthering my Dipterology skills! Judy Webb’s inspirational talk and fantastic videos on rearing larvae has made me want to try rearing some of my own! And thank you to the committee members for awarding me a bursary to attend the course 🙂 Thank you also to the staff at the centre who helped organise the weekend, sort out all of the equipment and looked after us. And another special thank you to the people who carried all of the fantastic museum specimens over to the centre for all of us to have a look at! We both look forward to attending more Dipterists Forum events in the future. For more information about the society and how to join follow the link below! 🙂

http://www.dipteristsforum.org.uk 

Oxford Coleopterists Day

This year was the third year I’ve had the pleasure of attending the Oxford Coleopterists Day, after being introduced to it in the third year of my undergrad by members of the Derbyshire and Nottinghamshire Entomological Society. And as expected, it was fantastic and definitely remains as one of my favourite, can’t miss, events of the year. It was also lovely to see so many younger people attending an entomological event! Thanks to Amo (@EntoAmo) for organising such an incredible day and Helen Roy (@UKLadybirds) for chairing the talks 🙂

The first talk of the day was on the genus Anthrenus in the Dermestidae by Graham Holloway. As most entomologists will know, the museum beetle (Anthrenus verbasci) is widely abhorred by many for eating our insect collections! But Graham provided an eye-opening talk, discussing how some species in the genus may only be rare because we choose to overlook them. A good example of his was ‘oh, it’s just a pigeon or a gull’, his response ‘well, how do you know?’. And I know I’m also guilty of this, ‘oh, it’s just a butterfly’. So, I think the take home message was, don’t overlook species because you think they’re common, because it might well not be what you think it is! The next talk was by Wil ‘the Ponker’ Heeney, who decided to put aside his longhorn beetle recording scheme (aside from a quick update) in favour of speaking about his finding of darkling beetles and journey into being a Coleopterist. Jordan Chetcuti (@JordanChetcuti) from the University of Leeds and the Centre for Hydrology and Ecology spoke to us about his PhD research on creating multi-species simulations of ground beetles. I loved all of the animations and we’re all interested to see how his PhD progresses over the coming years!

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And possibly my favourite terms of the day were ‘squishy beetles’ and ‘squishy journey’, with Steph Skipp speaking about her role as a trainee for the future at the NHM and her work with Cantharids and the Cantharidae recording scheme. This talk has definitely made me want to go out and record some of these wonderfully squishy beetles this year! This was followed by a ‘rant’ on why more people should study beetles by Richard Jones. Seizing the chance to plug his newly published book on beetles, Richard spoke about the importance of not only spreading interest and joy in the study of beetles (and insects in general), but also emphasized that we as entomologists had a duty to educate and defend the value of collecting specimens for science.

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Just before we attended the afternoon workshop, we had the opportunity to look at the fantastic collections behind the scenes at the museum. Alex became rather absorbed in the weevil collection (see one of his awesome pictures below!). Darren Mann (@BlattaMann) then took centre stage in the afternoon to run a workshop on the Aphodinii, a group of small but occasionally complex dung beetles. Alex brought along a few of his collected specimens to identify after Darren ran us through some of their morphological differences. The session proved more popular than Darren and the team were expecting, with people gathering in the corridor behind just to listen in. If you like dung beetles and would like to identify and record them, then be sure to check out Team Dump’s website (https://dungbeetlemap.wordpress.com) and follow them on Twitter (@Team_DUMP).

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The Coleopterists day also provides the opportunity to see some of my favourite people in the world. If anyone knows Dave Budworth, they’ll know what a character he is, and an absolutely incredible entomologist. And naturally, as the treasurer of DaNES, he was after our subs money, yet again. Another fantastic entomologist I had the pleasure of seeing again was Darren Clarke, chairman of DaNES, fantastic entomologist and completely eccentric. Both of these men are very much father figures, and probably the two most influential men in the start of my entomological career. So, if you live in Derbyshire or Nottinghamshire, I’d highly recommend joining the society and following them on twitter (@DaNES_Insects)!

Please check out the national recording schemes on twitter (@NLonghornRS, @SilphidaeUk, @WeevilRS) and the coleopteran recording schemes (http://www.coleoptera.org.uk/recording-schemes) and the inspirational people who run them! I’ll hopefully be doing some beetle recording of my own this year. Already looking forward to next year’s event (16th Coleopterists Day – 09.02.2019), see you there 🙂

Coauthored by Alex (@AlexLikesFlies)

 

2018 BBRO Winter Technical Meetings

On the 6th and the 8th of February this year, I had the opportunity to attend and introduce myself to the attendees of the BBRO Winter Technical meetings. These meetings occur within the first months of the year and provide a chance for sugar beet growers and other interested parties to see what the BBRO and its PhD students have been up to over the previous year, and allows the BBRO to address key subjects that are important to the growers! The theme for this year was ‘thinking differently’, and some of the issues addressed included the potential neonicotinoid ban and how the BBRO have been addressing issues that growers had previously highlighted. One of my favourite things about the day was that questions were mixed in between the presentations, and that the audience could answer these using fancy voting clickers, letting the BBRO know what the growers thought were the most important issues facing them in the future.

The first speaker of the day was guest speaker Hazel Doonan from the Agricultural Industries Confederation speaking about the future of neonicotinoids. This talk was really interesting as she explained the process of insecticide approval in the EU and a timeline of progress and key dates regarding the current neonicotinoid debate. She also has a fondness for the bees, and she discussed ways to help honeybees, bumblebees and solitary bees in the field. The second speaker was the BBRO’s own Dr Mark Stevens (Head of Science) discussing the impact of neonicotinoids on the sugar beet crop; including control of leaf miners.

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Next up it was the PhD students turn from the University of Nottingham (@UoN_Beet_team). Amongst the PhD students is an even rarer breed of person than the already rare entomologist, a nematologist! Alistair Wright is a fourth year PhD student working on the beet cyst nematode and was the first student speaker of the day. He discussed some of the work he’d been doing on resistant varieties and showed some amazing drone and live nematode footage for the audience. Next up was Jake Richards, a third year PhD student working on the effects of cover crops on soil structure and sugar beet yield. We also had Tamara and Georgina. Tamara is another 4th year PhD student working on water uptake in sugar beet, focusing on the below ground system with some very lovely pictures showing how xylem varied depending on the depths of the root. Georgina is a 2nd year PhD student working on water use efficiency of sugar beet, with a focus on the water uptake through the stomata in the canopy of the crop. And then it was my turn to introduce my PhD!

After the break Stephen Briggs, the second guest speaker of the day, from the Innovation of Agriculture discussed soil health. There was a lovely emphasis on the importance of soil fauna in this talk, particularly addressing the importance of earthworm recording using a variety of different tools including the OPAL guide! Then the BBRO team took to the stage to discuss some of the projects they’ve been working on during 2017. First up was Dr Mark Stevens discussing some of the foliar diseases seen in sugar beet and the results of the BBRO fungicide trials. Also mentioned was the BBRO plant clinic and how this helps with identifying foliar diseases, so do send in samples! And then it was over to Dr Simon Bowen, discussing some of the 2017 crop progression and recovery projects with a key message ‘don’t judge your crops by their colours’, as there were many differences seen in the characteristics of different sugar beet varieties through some of their work. The stage was then handed over to Dr Toby Townsend who is working with the BBRO on the BeetGro model, followed bySimon speaking about some of the results and advantages of entering your sugar beet field into the Beet Yield Competition. And last up was Stephen Aldis, speaking about his role in the BBRO and the results from the harvester testing programme.

It was quite different for me to speak in front of a large number of people (around 380 attendees in total) compared to the usual 20-30 other students in a classroom (at most!) and I was quite nervous. And although I knew when I applied for this PhD that there was significant application for its findings to be disseminated to sugar beet growers, actually standing up in front of some of the people this work might affect put a lot of things into perspective for me, even if I was only speaking for a whole 2 minutes! So, I was surprisingly pleased and relieved by the number of people who came and spoke to me during the breaks to ask questions and offer their support. At some point in the near future, I will be setting up a website/blog section to ask for help in sending in samples of sugar beet leaf miner across the country. So, if you’re interested in helping me collect some samples of Pegomya sp. please let know or keep an eye out as I’ll be sending out a call for help soon! 🙂

BBRO LOGO

Thanks to the BBRO team for all the support they’ve given me so far and my lovely banner and to my supervisor Lewis who took the time out of his busy schedule to attend the first meeting! And a special thanks to Debbie Sparkes (@DebbieSparkes), our chairwoman for the day and Ches for organising such wonderful events. I’ll look forward to working with you on my placement in the summer! For more information on the BBRO visit their website (https://bbro.co.uk) or follow them on twitter (@BBRO_research/@BBRO_Beet) 🙂

Starting my PhD!

Hello! 🙂 It’s been a while since I last posted on my blog but I’m hoping to start using it much more over the course of the next few years. And it isn’t going to be just aphids now, I’ll also be talking about some of the botanical and wider entomological things I get up to as well! But most importantly, I’ll be talking about what I’m getting up to during my PhD – which is on flies!

Specifically, these flies.

 

 

Left: Pegomya hyoscyami. Right: Pegomya betae.

Photographs I took of specimens from the World Museum in Liverpool before Christmas.

 A special thank you to Tony Hunter for all of your help during my visit!

I started my PhD ‘Population genetics and ecology of the sugar beet leaf miners’ at the University of East Anglia in October as a student of the BBSRC funded NRP DTP partnership with Norwich Research Park. This programme is full of collaborations between the University of East Anglia, John Innes Centre, Quadram Institute, The Sainsbury Laboratory and the Earlham Institute. I’m also lucky as my PhD is a part of the iCASE programme with my iCASE partners being the British Beet Research Organisation (BBRO)! I have an outstanding supervisory team. Three of my supervisors are based at UEA, including my primary supervisor Dr Lewis Spurgin and Prof Tracey Chapman and Prof Matt Gage (aka the dream team, in the words of another PhD student here at UEA). From my BBRO partners I have the wonderful Dr Mark Stevens (now Head of Science) and I’m also really lucky as Dr Ian Bedford from the John Innes Centre is also on my supervisory team! So, my PhD involves a collaboration between UEA, JIC and the BBRO! And you’ll hear more about the BBRO and what they do in future blog posts 🙂

About the Mangold fly

These guys (P. hyoscyami & P. betae) are known as the Mangold fly, or the sugar beet leaf miners, and are anthomyiid leaf mining pests of sugar beet (Beta vulgaris spp. vulgaris). Although it isn’t a major pest of sugar beet like some aphid species are, it can cause reduction in crop canopy, which results in storage loss within the crop and therefore sugar loss. It has been a particular problem in the last few years, as growers have seen an increase in its distribution across the UK. The second and third generations have been the main cause for concern in past seasons as neonicotinoid seed coatings provide protection against larvae of the first generation that occur around April time. But with the uncertainty on the future use of neonicotinoid seed coating in sugar beet, the first generation may possibly be a future problem for growers if there are no other alternatives for the control of the fly. However! That’s where my PhD may help.

MANGOLD FLYYY

Mangold fly specimen from my visit to the Natural History Museum in November

Thank you to Nigel Wyatt for arranging my visit and to the awesome Erica McAlister – for signing my book!

The aim of this PhD is to develop a greater understanding of the sugar beet leaf miners’ biology and ecology with the prospect of using that knowledge in future alternative controls of the species. To do this we will be using an integrated taxonomy approach, utilising traditional taxonomic methods as well as molecular methods to identify the species at a genetic level and determining how many species of sugar beet leaf miners there are. We will also be looking into the species life history traits, their distribution, alternative host plants and their parasitoids.

So that was very brief overview of my PhD! I plan to write more on my blog about the things that I’ll be getting up to with the BBRO and the JIC, as well as other entomological/botanical activities I’m getting up to during my time in Norwich. There will be another short blog specifically on the what is known about the species soon! I’d like to especially thank my supervisors for all the help they’ve given me so far, and I’m really looking forward to the rest of my PhD! If anyone has any suggestions or knows something about this species then please get in touch!

See you again soon… 🙂

 

 

 

Aphids: The Evolution…

Hello again! In the last post we discussed some of the research regarding aphid origins and paleontology, as well as some of the questions that Heie (2009) wanted answering. We briefly covered one of the main influences on aphid evolution – the host plants. In this post I’ll be discussing some of the key points about host plants in regards to aphid evolution and also some interesting things about their unique morphology.

Sit back, close your eyes and imagine you have traveled back to a time where magnificent dinosaurs rule the earth. However, despite what most children’s shows and textbooks will tell you, dinosaurs aren’t the only animals roaming here. Also, don’t close your eyes for too long, the impact of a written article is diminished if it isn’t actually read.

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*Photo Credit: Julian Beniers “Clever Girl” (Not the right scene but hey-ho!)

Interactions between insects and their plant hosts can be considered to be very sensitive. This relationship has been used to investigate the evolutionary histories of many insect species, including the aphids. There are two main theories as to how this relationship may have affected the evolution of both parties;

  • Cospeciation
  • Speciation via the changing of hosts

The first theory eludes to the evolution of both insect and host at the same time, resulting in similar phylogenetic trees. The second refers to the ‘host parasite’ changing its host a number of times, resulting in a literal change in the characteristics of the host parasite.

Although some aphids aren’t necessarily picky with their choice of host plant, many are still considered to have very specific relationships with them. This can be seen when comparing the diversity of some plant species with the aphids that colonise them. The Compositae (around 19,000 sp.) host over 600 species of aphids, which is similar in number to many other plant groups. This can be compared to other groups such as the Coniferae (around 400 sp.) which hosts around 363 species of aphid. Aphids during the later geographical periods would have originally fed upon ancient gymnosperms as angiosperms had not occurred prior to the Cretaceous. However, the evolution and diversification of flowering plants is often regarded as the defining factor that drove aphid evolution which resulted in the aphids that we see today.

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* Geographical Time Scale and Plant Evolution

Another factor that will have affected evolution is that of the aphid life cycles. Aphids are divided into non-host alternating (Autoecious), or host alternating (Heteroecious).

Host alternation is a strategy only adapted in around 10% of aphid species but is thought to have significantly contributed towards the colonisation of a wider range of plants and thus has partially driven the evolution of the aphids. A large number of aphids specialise and only feed on one or a few species of plants, whereas host alternation usually occurs seasonally between a woody winter host plant and a secondary summer host that is usually an herbaceous plant species. This constant shift between hosts may have been a deciding factor for the speciation of some aphids prior to present day taxonomy.

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*A) Life cycle of the sycamore aphid, Drepanosiphum platanoidis (Autoecious). B) Life cycle of the bird cherry-oat aphid, Rhopalosiphum padi (Heteroecious).

The Aphididae is made up of around 5000 species. The super family Aphidoidea can be considered as aphids which possess siphunculi or siphuncular pores, which would not have been present in most aphid families that existed prior to or during the Cretaceous. One of the questions Heie asks is “where does the family Lachnidae belong on the phylogenetic tree?” I won’t go too much into aphid Phylogenetics because it would need several posts of its own to even begin to cover it in enough detail. So this will be a very brief overview, which I will return to in more detail in future posts.

Aphids of the family Lachnidae are generally brownish in colour, covered in a dense layer of hairs or setae and are (in most species) ‘farmed’ by ants. The oldest known fossils of this family date to the middle Tertiary and are thought to have originated from temperate regions in the Northern hemisphere. The Lachnidae have been through many changes in their taxonomy through the years (see the table below for a brief history!) but in 2015 a paper was published with some updated information on this group of aphids.

Taxonomist Date of Literature Taxonomy
BURMEISTER, 1835 Koch, 1854 Genus – Lachnus
HERRICH-SCHAEFFER Koch, 1857 Family – Lachnidae
Baker, 1920 Lachnidae = Tribe within Aphidinae
Börner, 1952. Heie, 1980 Family – Lachnidae

So are the Lachnidae a primitive group of aphids or a relatively young group in the world of aphid phylogeny? Older (pre-1960’s) literature regarded the Lachnidae as one of the more primitive groups of aphids, but Heie (along with others) disputed this, saying that they are in fact one of the more recent divergences. This may be due to a lack of diversity within the Lachnidae up to the later Tertiary compared to its diversity today. Based on morphology, the Lachnidae have also been considered as the sister group of the Aphididae due to similarities in the presence of wax glands, the oval secondary rhinaria and because some species appear to be morphologically similar.

Molecular studies on this family have also found some contradiction in the evolutionary history of the Lachnidae. One study (see Ortiz-Rivas & Martinez-Torres, 2010) looking at a range of aphid species discovered that the Lachnidae are only distantly related to the Aphididae and that they represent one of the earlier branches in aphid phylogenetic history. The other study (see Novàkovà et al. 2013) utilises the aphid symbiont Buchnera and found that the Lachnidae may be the sister group of the Drepanosiphidae, so may originate from a branch in aphid phylogenetics that is very distant from the branch of the Aphididae. The latter results may be due to mutations in Buchnera or cross contamination between individuals over time.

So it seems as if this topic is still up to some debate between the researchers! See Heie, 2015 in the references below for a more thorough examination of this topic 🙂

Aphids: The Evolution Part 2 – Morphology will be released at the beginning of April (once my coursework exams are all finished!). I hope you enjoyed reading, leave me a comment if you have any questions or suggestions!

I hope to see you again soon 🙂

Picture References

“Clever Girl” by Julian Beniers. Background: http://www.geocities.ws/jp_dinosaurs/compy.html Aphid: https://nl.pinterest.com/kingpiratedog/aphids/

Geographic Time Scale (plant): from https://www.britannica.com/science/Mesozoic-Era

Life cycle image: from http://what-when-how.com/insects/sternorrhyncha-jumping-plant-lice-whiteflies-aphids-and-scale-insects/

References

Dixon, A.F. and Kundu, R.A.N.A.J.I.T., 1994. Ecology of host alternation in aphids. European Journal of Entomology. 91(1), pp.63-70.

Heie, O.E. 2015. A theory about the evolutionary history of Lachnidae and comments on the results of some molecular phylogenetic studies of aphids (Hemiptera: Aphidoidea). Polish Journal of Entomology. 84, pp.275-287.

Huang, X.L., Xiang‐Yu, J.G., Ren, S.S., Zhang, R.L., Zhang, Y.P. and Qiao, G.X. 2012. Molecular phylogeny and divergence times of Hormaphidinae (Hemiptera: Aphididae) indicate Late Cretaceous tribal diversification. Zoological journal of the Linnean Society. 165(1), pp.73-87.

Kim, H., Lee, S. and Jang, Y. 2011. Macroevolutionary patterns in the Aphidini aphids (Hemiptera: Aphididae): diversification, host association, and biogeographic origins. Plos One. 6(9), p.e24749.

Labandeira, C.C. and Phillips, T.L. 1996. Insect fluid-feeding on Upper Pennsylvanian tree ferns (Palaeodictyoptera, Marattiales) and the early history of the piercing-and-sucking functional feeding group. Annals of the Entomological Society of America, 89(2), pp.157-183.

Moran, N.A., Kaplan, M.E., Gelsey, M.J., Murphy, T.G. & Scholes, E.A. (1999). Phylogenetics and evolution of the aphid genus Uroleucon based on mitochondrial and nuclear DNA sequences. Systematic Entomology. 24, pp.85-93.

Novàkovà E., Hypša V., Klein J., Foottit R.G., Von Dohlen C.D. and Moran N.A. 2013. Reconstructing the phylogeny of aphids (Hemiptera: Aphididae) using DNA of the obligate symbiont Buchnera aphidicola. Molecular Phylogenetics and Evolution. 68(1), pp.42–54.

Ortiz-Rivas B. and Martinez-Torres D. 2010. Combination of molecular data support the existence of three main lineages in the phylogeny of aphids (Hemiptera: Aphididae) and the basal position of the subfamily Lachninae. Molecular Phylogenetics and Evolution. 55(1), pp.305–317.

Peccoud, J. Simon, J.C. von Dohlen, C. Coeur d’acier, A., Plantegenest, M., Vanlerberghe-Masutti, F. & Jousselin, E. (2010). Evolutionary history of aphid-plant associations and their role in aphid diversification. Comptes rendus biologies. 333(6), pp.474-487.

Recommended: Aphid Ecology, 2nd Edition. A.F.G. Dixon.

Aphid Mysteries – Unraveling the past 

Hi! As you may already know, this year I started my masters in Entomology at Harper Adams University where I’m hoping to nurture my passion for aphids. Luckily, the course has an amazing team of entomologists, including Professor Simon Leather, whose research on aphids I’m a big fan of!

He happened to recommend a paper to me called ‘Aphid Mysteries’ by Heie (2009), a Danish entomologist who has studied aphids extensively. This paper was fascinating, and although it was written relatively recently I was interested to see how much research has since been done on aphids. And so I have decided to write my first blog post about where we are now in aphid research.

Heie’s paper considers questions about aphids which hadn’t been answered by any of the published literature of the time, such. These unknowns are (or were) related to the following:

  • The choice of host plant
  • Host alternation
  • Variation in size of population
  • Morphology
  • Geographical distribution
  • Palaeontology
  • Evolution

This first blog will be split into three sections starting here with the palaeontological evidence of aphids and geographical locations. The other points made above will be addressed in the following two blog posts!

The Origins

The aim of this post is to give a very brief overview of some of the published information on the origins of aphids and their fossils – but by no means will this cover the whole topic in as much detail as the subject may deserve. So think of this as a taster session!

In 2009 (the year of Heie’s journal publication), it was unknown whereabouts in the world aphids originated from – the Northern or the Southern hemisphere? When I delved into the literature on the subject, I found that there was a very mixed consensus, depending on which angle you come from.

Looking at the geographical locations of modern aphids, the majority of species are located in the Northern hemisphere, which is in contrast to most other insects, which increase in biodiversity both at and south of the equator. It would seem safe to assume that this was also the case in their evolutionary history as well. However, some research disputes this assumption. It is thought that the distribution of aphids today is due to a species radiation in some lineages of aphids found in the Northern hemisphere that took place in the Tertiary period. During this radiation, the tropics would have therefore presented a geographical barrier that many species would not have been able to overcome during migration to the South. Another theory about the current distribution of aphids is that they could also be well adapted to colder climates because of the winter host phase in their life cycle (this will be explained further in a future blog – keep your eyes peeled!)

sp-richness-heie-1994

*The species richness of aphids in a number of different areas across the world (from Heie, 1994).

The largest family of aphids, the Aphididae, contains species which are largely present across Northern Asia, Northern Europe and North America. This family is divided into 27 subfamilies, including the Aphidinae which hosts some of the world’s major pest species and dominates temperate regions of the Northern hemisphere and subtropical regions. The wide distribution range of the Aphididae causes some suspicion on the topic of aphid origins. It is thought that the Aphididae likely diverged from a common ancestor, Adelgidae or Phylloxeridae, during the Cretaceous. A study carried out in New Zealand found that endemic aphids of the tribe Aphidini (of the Aphidinae) had been present in the Southern hemisphere from at least the Lower Miocene (23.3 to 15.9 million years ago) and possibly even before then.*The species richness of aphids in a number of different areas across the world (from Heie, 1994).

So what about the fossil records?

It is pretty amazing that aphids have become fossilised considering they have soft bodies and are relatively small in size. But luckily there are quite a few fossil records out there. The fossilised wing of perhaps the most well-known fossil aphid recorded, Triassoaphis cubitus (Evans), was discovered in Australia and would have lived during the Triassic period. Other wing fossils, such as Ceraphis theodora (Shcherbakov) from Middle Asia, and Leaphis prima (Shcherbakov) from the Vosges France, have also been found to date back to the Triassic. The only whole body specimen (or almost –part of the antenna and parts of some of the legs were missing) from the middle Triassic, Dracaphis angustata (Hong), was also discovered in China.

geo-ts

*Geographic Time Scale

There are multiple other fossils specimens that have been discovered from the Cretaceous and Jurassic. Penaphis woollardi (Jarzembowski) was discovered in southern England and is thought to have existed during the Early Cretaceous. It may have been one of the first aphids to feed on the ancient gymnosperms. The first fossil aphid from Africa, Siphonophoroides orapaensis (Rayner) – this species was not confidently assigned to this lineage and has therefore been placed in this genera due to some similarities with other extant species. S. orapaenis was discovered in the Orapa kimberlite crater (amongst many other insects) and is thought to have also existed during the Cretaceous period. A few aphids from Denmark have also been found, such as the alate morph of Diatomyzus eocaenicus (Heie) from the Lower Eocene.

Up until recently, the Triassic was the period which contained the oldest recorded fossil aphids. In 2014 a paper was published on the discovery of an aphid dating back to the Palaeozoic era, in the middle Permian. This new species, Lutevanaphis permiana (Szwedo), found in the Lodève Basin in Southern France, now represents the oldest fossil specimen from the Aphidomorpha currently known.

szwedo-2014-wing

*A) A reconstruction of wing venation pattern. B) Holotype specimen (from Szwedo et al. 2014)

Aphids are also famously closely associated with several other species such as ants, host plants and specialist aphid parasitoids, so is it possible that fossil records of these species could also be used to figure out where aphids originate from?

The ancient gymnosperms that are presumed to have hosted aphids in the past were present in the Southern hemisphere. Although there are few lineages of aphids that are native to the southern hemisphere today, the assumption that they were also there at some point in the past makes sense. (But more on this in the next post!)

geo-plant-ts

*Geographical Time Scale and Plant Evolution

Specialist parasitoids also have close relationships with aphids and are often used as a biocontrol method in controlling aphid population due to their shortened ovipositor that is specially adapted for inserting into an aphid. In 2009 a piece of Albanian amber was recovered from a site in Spain which contained an Aphidiine parasitoid wasp. Research on this species concluded that this ancient and previously undiscovered species, Archephedrus stolamissus (Ortega-Blanco), from the Braconidae, originated from the Northern hemisphere rather than the Southern hemisphere which was previously thought to have been the case. In former literature it was speculated that the Aphidiine originated in the Southern hemisphere based on the location of several Southern genera (see Belshaw in the reference list below). This newer research suggests that members of the Aphidiine were already present in the Northern hemisphere during the later Cretaceous.

ortega-2009-wasp

*Illustration of the Holotype male Archephedrus stolamissus, a new genus and species (from Ortega-Blanco et al. 2009).

The oldest of all described fossil aphids have been discovered either in China or Australia, which may suggest that aphids originally existed in these Eastern parts of the world before spreading into other areas such as Europe. But the evidence of fossil aphids cannot be used alone as there may be some bias in the areas where the most fossils are preserved. When looking at those species that have close relationships with the aphids there is a mixed opinion on their origins and therefore no definite conclusion has been made based on these facts. Based on the fossil evidence it may also be likely that more aphids from earlier time periods just haven’t been discovered yet.

I would love to hear your opinions on this topic so please leave any comments below. The evolution of aphids and their morphology will be continued in the next blog post, which should be up within the next few weeks! Thank you for reading and I hope you find it interesting J See you again soon!

Picture References

Species richness table: from Heie, 1994.

Geographic Time Scale: from https://www.bgs.ac.uk/discoveringGeology/time/timechart/home.html?src=topNav

Geographic Time Scale (plant): from https://www.britannica.com/science/Mesozoic-Era

Holotype specimen & wing venation of Lutevanaphis permiana: from Szwedo et al. 2014.

Holotype male Archephedrus stolamissus: Ortega-Blanco et al. 2009

Text References

Belshaw, R., Dowton, M., Quicke, D.L.J. & Austin, A.D. (2000). Estimating ancestral geographical distributions: a Gondwanan origin for aphid parasitoids? Proceedings of the Royal Society of London B: Biological Sciences. 267(1442), pp.491-496.

Heie, O.E. (1970). Lower Eocene aphids (Insecta) from Denmark. Bulletin of the Geological Society of Denmark. 20(2), pp.162-168.

Heie, O.E. (1994). Why are there so few aphid species in the temperate areas of the southern hemisphere? European Journal of Entomology. 91, pp.127-133.

Hong, Y., Zhang, Z., Guo, X. & Heie, O.E. (2009). A new species representing the oldest aphid (Hemiptera, Aphidomorpha) from the Middle Triassic of China. Journal of Palaeontology. 83(5), pp.826-831.

Jarembowski, E.A. (1989). A fossil aphid (Insecta: Hemiptera) from the Early Cretaceous of southern England. Cretaceous Research, 10, pp.239-248.

Moran, N.A., Kaplan, M.E., Gelsey, M.J., Murphy, T.G. & Scholes, E.A. (1999). Phylogenetics and evolution of the aphid genus Uroleucon based on mitochondrial and nuclear DNA sequences. Systematic Entomology. 24, pp.85-93.

Ortega-Blanco, J., Bennett, D.J., Delclòs, S. & Engel, M.S. (2009). A primitive Aphidiine wasp in Albanian amber from Spain and a Northern hemisphere origin for the subfamily (Hymenoptera: Braconidae: Aphidiinae). Journal of the Kansas Entomological Society. 82(4), pp.273-282.

Peccoud, J. Simon, J.C. von Dohlen, C. Coeur d’acier, A., Plantegenest, M., Vanlerberghe-Masutti, F. & Jousselin, E. (2010). Evolutionary history of aphid-plant associations and their role in aphid diversification. Comptes rendus biologies. 333(6), pp.474-487.

Rayner, R.J. & Waters, S.B. (1989). A new aphid from the Cretacous of Botswana. Paleontology. 32(3), pp.669-673.

Shcherbakov, D.E. & Wegierek, P. (1991). Creaphididae, A new and the oldest fossil family from the Triassic of Middle Asia. Psyche. 98(1), pp.81-85.

Szwedo, J. & Nel, A. (2011). The oldest aphid insect from the Middle Triassic of the Vosges, France. Acta Palaeontologica Polonica. 56(4), pp.757-766.

Szwedo, J., Lapeyrie, J. & Nel, A. (2014). Rooting down the aphid’s tree – the oldest record of the Aphidomorpha lineage from the Palaeozoic (Insecta: Hemiptera). Systematic Entomology. 40(1), pp.207-213.

Von Dohlen, C.D. & Teulon, D.A.J. (2003). Phylogeny and historical biogeography of New Zealand indigenous Aphidini aphids (Hemiptera, Aphididae): An hypothesis. Annals of the Entomological Society of America. 96(2), pp.107-116.

Recommended Authors – Heie & Von Dohlen.

Useful website – http://aphid.speciesfile.org/HomePage/Aphid/HomePage.aspx