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10 Posts tagged with the entomology tag
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Many species and larger taxonomic groups, especially invertebrates, have been little studied in terms of their patterns of geographical distribution - biogeography - and even basic information, inventories and assessments are missing.  A key reason for this is that collecting and sampling has been too limited and too uneven: there are simply no good baseline data on distributions.

 

Ian Kitching of the NHM Life Sciences Department, with colleagues from the University of Basel, Switzerland, and Yale University, USA, set out to establish why inventories for the hawkmoths of Sub-Saharan Africa are incomplete, considering human geographical and associated environmental factors.

 

xanthopan-morganii-praedicta-madagascan-sphinx-moth-_105466_1.jpg
Xanthopan morganii praedicta - a hawkmoth found in Madagascar and East Africa

 

They used a database of hawkmoth distribution records to estimate species richness across 200 x 200 km map grid cells and then used mathematical models predict species richness and  map region-wide diversity patterns. Next, they estimated cell-wide inventory completeness related to human geographical factors.

 

They found that the observed patterns of hawkmoth species richness are strongly determined by the number of available records in grid cells. Vegetation type is an important factor in estimated total richness, together with heat, energy availability and topography. Their model identified three centres of diversity: Cameroon coastal mountains, and the northern and southern East African mountain areas. Species richness is still under-recorded in the western Congo Basin and in southern Tanzania/Mozambique.

 

What does this mean?  It means that sampling (and therefore our knowledge) of biodiversity is heavily biased.  We have good data and information where there is higher population density; for more accessible and less remote areas; for protected areas and for certain areas where there was collecting in colonial periods.  If it is easy to get to, not too difficult to access, there are more people around and there have been longer histories of collecting: we have better knowledge. 

 

This is important in how we understand biodiversity and in how we make decisions with our knowledge to protect forests or other areas.  But this study means that we can take account of data gaps if we are looking at larger scale patterns of diversity.  It shows that baselines for broad diversity patterns can be developed using models and what data there is available.  We can identify the "known unknowns" in terms of information gaps in part by looking at human geographical features - the models can help set priorities for future exploration and collection as well as informing our understanding of biodiveristy.


Ballesteros-Mejia, L., Kitching, I.J., Jetz, W., Nagel, P. & Beck, J. 2013. Mapping the biodiversity of tropical insects: species richness and inventory completeness of African sphingid moths. Global Ecology & Biogeography 22: 586-595. (doi: 10.1111/geb.12039)

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Michael Kuhlmann and colleagues have put the beta version of the “Checklist of Western Palaearctic Bees” online (http://westpalbees.myspecies.info) using the NHM-developed Scratchpads as a platform.

 

Bees are the most important pollinators worldwide and the checklist provides access to taxonomic information and distribution data on country level to about 3350 bee species in 102 genera in the western Palaearctic region, with almost 2000 species recorded for Europe alone. The site contains regularly updated information from both published and unpublished sources including data from a whole range of private and public collections that are provided by European wild bee experts. The checklist reflects the current state of knowledge on the taxonomy and distribution of western Palaearctic bees, making it a prime source of information not only for taxonomists but also ecologists and agricultural scientists.

 

The checklist project started in 2008 and it quickly became clear that taxonomic expertise is globally lacking for several genera and that this gap is likely to grow quickly due to the progressive ageing of the community of bee taxonomists . The places most heavily affected by the loss of taxonomic knowledge are the “hotspots” of species diversity and endemism around the Mediterranean, in Turkey and the Middle East. Unfortunately, these are the areas that are most likely to be heavily affected by climate and landscape change. For this reason it seems possible that most of the predicted changes and losses of unique fauna will go unnoticed.

 

IMG_0579.jpgBombus (Pyrobombus) pratorum, the early bumblebee on Pentaglottis sempervirens

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Life Sciences Seminar

 

Sap-suckers of the Tree of Life: how closely are they related to their feeding branches?

 

 

David Ouvrard

Terrestrial Invertebrates, Dept. of Life Sciences, NHM

 

Wednesday 19 of December 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)

 

 

Sternorrhyncha comprise four super-families among the most damaging agricultural pests. Furthermore, Coccoidea (scale insects - 8000 species), Aphidoidea (aphids, phylloxerans, and adelgids - 5000 species), Psylloidea (jumping plant-lice - 3800 species) and Aleyrodoidea (whiteflies - 1500 species) are driving ecosystems as primary consumers of phloem sap. Various degrees of insect/plant associations, from strict monophagy to high polyphagy, are observed among them and at different classification levels.

 

Until now, several assumptions of co- or ‘parallel-’ evolution between the insects and their host-plants have been made, but rarely using a phylogenetic framework to test these hypotheses. Focusing on Psylloidea, I will trace the macroevolution of these phytophagous insects, from fossil proto-homopterans to the extant fauna, based on the evolution of some striking morphological characters.

 

In parallel, the large-scale analysis of patterns of associations between insects and plants has been made possible using the global datasets compiled and organised in databases such as “Psyl’list” or “White-Files”, originally oriented towards taxonomic information dissemination only. The synthesis of recent taxonomic studies into a revised classification of the Psylloidea offers a framework for further phylogenetic reconstructions, a research basis in the fields of Ecology and Conservation, as well as a management tool for collaborators involved in Integrated Pest Management

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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Thomas Simonsen has published an invited peer-reviewed paper in Arthropod Structure and Development in collaboration with co-workers from the Finnish Museum of Natural History and Naturalis (Dutch Museum of Natural History) on the continuing importance of morphology in Lepidoptera systematics.

 

Taxonomy and systematics are areas of science that are focused on description, naming, classification and evolutionary relationships of living things.  Such science is the fundamental reason for the existence of large natural history collections, and traditionally the focus has been on morphology - the use of combinations of physical characters such as number of legs, wing patterns or body form.  The differences in these characters between species can be compared and allow identification - so a fly will have one pair of wings but a bee will have two pairs, for example. Over time, different species and groups have diverged as a result of evolution and in general become progressively more different in form.

 

However, while morphology is a key tool in understanding diversity, evolutionary difference can be seen also in molecules, particularly DNA.  DNA of different species can be compared and the degree of difference used to assess patterns of evolution and relationships.  The use of DNA in taxonomy and systematics is of increasing importance and museum collections are of great value in this new science - a purpose never suspected by those who started to assemble them in the 18th and 19th Centuries.

 

Wallace birdwing NaturalHistoryMuseum_PictureLibrary_056153_IA.jpgOrnithoptera croesus, Wallace's golden birdwing butterfly - a member of the Paplionidae family

 

Some scientists have argued that DNA alone will be used in future to assess diversity and to identify species: it is after all DNA differences that are the root cause of morphological difference - so why use both?  There are in fact a number of reasons why morphological techniques will be of continuing importance - Thomas and colleagues explore the relative value of morphology and molecular information for large groups of butterflies in this paper.

 

They reviewed the morphological characters that are important for understanding butterfly phylogeny and evolution in the context of large-scale molecular phylogenies (evolutionary classifications) of the group. In particular, they were interested in what the molecular evidence was able to tell them about the evolution of morphological features - so for example, were characters that are used to separate distantly related groups actually caused by large genetic differences?

 

They looked in particular at the families Papilionidae, Nymphalidae and Hesperiidae which have all been studied with a combination of morphological and molecular data in recent years. What they found was that a  scientifically more valuable classification emerged not from using either molecular or morphological techniques, but from using both in combination. They argue that morphology still has an immensely important role to play in butterfly (and insect) phylogenetics - including its value in understanding how the whole organism is important in evolutionary changes, natural selection and diversity.  

 

Simonsen, T. J., de Jong, R., Heikkilä, M. & Kaila, L. (2012). Butterfly morphology in a molecular age – does it still matter in butterfly systematics? Arthropod Structure and Development. 41: pp. 307-322.

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What can psyllids tell us that other bugs can't?
A non-model model organism for studying plant-insect interactions

 

Diana Percy

Terrestrial Invertebrates, Dept.of Life Sciences, NHM

 

Wednesday 28 of November 11:00
Sir Neil Chalmers seminar room, Darwin Centre LG16 (below Attenborough studio)


Psyllids exhibit the greatest degree of host specificity amongst the sternorrhynchan plant-feeders, and they are the only members of this group to have retained a complex vibrational communication system [sound and light show includes backup band]. But can psyllids reveal things that studying other bugs can't? I will present examples of how systematic analyses of psyllid lineages can provide remarkable insights into host mediated diversification. From modest beginnings of “who eats what where?”, we can build up a picture of how these observed plant-insect interactions came to be. Combining these observations with molecular systematics and genomics approaches will help us interpret the past and look into the future to make predictions of “who will eat what where?” – the psyllid version of “eats shoots and leaves”.

 

 

For additional details on attending this or other seminars see http://www.nhm.ac.uk/research-curation/seminars-events/index.html

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Steve Brooks from the Museum and collaborators from UCL, the universities of Nottingham, Bergen and Liverpool, and the RSPB have been examining reasons for the breeding success of the Slavonian grebe Podiceps auritus. The Slavonian grebe has a UK breeding population of only 29 pairs, found in NE Scotland only since 1908.  Loch Ruthven holds the largest British population in an RSPB reserve and breeding success is known to have fluctuated annually since records began in 1970.

 

Slavonian grebe audubon (c) NHM small.jpgSlavonian grebe from Audubon's Birds of America    © Natural History Museum

 

 

The research looked at whether the fluctuations are linked to the numbers of chironomids, the group of flies on which Steve is an expert.  These midges are an important food-source for the grebe chicks.

 

The team analysed a sediment core from the lake by slicing it into 2.5-mm sections to separate sediment on a yearly basis.  In this sediment, they looked at the remains of chironomids, diatoms (planktonic algae which show strong seasonal trends in populations) and algal pigments.   These plant data were used to deduce changes in total phosphorus in the water and to see whether there was a link between algae and the abundance of chironomids. Trends in grebe breeding success, chironomid abundance and algal populations were analysed against climate data to clarify whether climate was the key factor behind all of these fluctuations.

 

The study shows that grebe breeding success is linked with chironomid abundance and chironomid abundance is linked with total phosphorus. Over the past 100 years, lake productivity and chironomid abundance have both risen, increasing more rapidly from the mid-twentieth century to the present. Fluctuations in grebe breeding success from 1970 followed the same pattern as chironomid variation, with a lag of one year. 

 

One of the questions of interest was whether grebe breeding success was influenced by climate variability year by year.  Because the Slavonian grebe is a relative newcomer to the UK, it is not clear how vulnerable this small population is to environmental change.  However. No correlation was found between grebe productivity or chironomid abundance and climate.  The team concludes that breeding success of the grebe depends on food availability in the form of chironomids at Loch Ruthven.

 

Brooks, SJ et al. Population trends in the Slavonian grebe Podiceps  auritus (L.) and Chironomidae (Diptera) at a Scottish loch  Journal of  Paleolimnology April 2012, Volume 47 (4) 631-644  doi: 10.1007/s10933-012-9587-4

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Different ideas of the relationship between the crustacea (crabs, barnacles, copepods and others) and insects have been discussed at length over the past century. The emergence of more and better DNA information is allowing the evolutionary relationships to be explored and clarified.


Ronald Jenner (Zoology) co-authored a first phylogenomic test of the recent hypothesis of a sister group relationship between hexapods (insects) and remipede crustaceans. Numerous data and testing of different interpretations led the authors to robustly find hexapods and remipedes as sister groups.


Remipede crustaceans were first described as Carboniferous fossils in the 1950s (around 310 million years old).  However, living species have been discovered since 1979, living only in underground aquifers connected to the sea. They are slow-moving with relatively basic segmented body plans, but can have specialised characteristics such as poison fangs and advanced sense of scent, important for securing prey in their unusual habitat.

 

NaturalHistoryMuseum_014472_Comp.JPG

A Remipede from Mexico

 

The paper looks at the idea of the Pancrustacea - a large group containing both crustaceans and insects.  The data support the idea that the Pancrustacea can be divided into two major groups.  In the first are the marine decapods (crabs, prawns and lobsters), barnacles and copepods.  In the second group are found the freshwater Branchiopoda (such as the familar waterflea Daphnia), the Remipedes and the insects.  This supports the insects as a part of the Pancrustacea, possibly as part of a subgroup that moved from shallow marine environments to specialist freshwater, groundwater and terrestrial habitats.

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von Reumont, B. M., Jenner, R. A., Wills, M. A., Dell’Ampio, E., Pass, G., Ebersberger, I., Meyer, B., Koenemann, S., Iliffe, T. M., Stamatakis, A., Niehuis, O., Meusemann, K. and Misof, B. Early online. Pancrustacean phylogeny in the light of new phylogenomic data: support for Remipedia as the sister group of Hexapoda. Molecular Biology and Evolution (doi:10.1093/molbev/msr270)  Abstract

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Adrian Pont from Entomology spent two weeks on fieldwork in Armenia, 16-29 July. This was the second of three projected visits to Armenia, within the framework of the International Science and Technology Center project “Molecular genetic monitoring of blood-sucking flies (Diptera) as a basis for biological control of vectors of dangerous infectious diseases and precautions against the acts of biological terrorism”

 

The 2010 fieldwork was in June and the projected 2012 fieldwork will be in May. In this way, the seasonal succession from spring, summer and high summer will have been covered. Samples were collected at 52 sites. 14 of these were during day-trips out from Yerevan to localities previously investigated in 2010, such as Tsakhkadzor at over 2300 m and Lake Kari at nearly 3200 m.  Adrian also spent a morning investigating the polluted River Hrazdan that runs through the centre of Yerevan. The other 40 sites were in the south-east of Armenia.

 

From 22 to 28 July inclusive, Adrian and his team drove to Meghri on the border with Iran and worked their way slowly back to Yerevan. His companions were a mosquito specialist and two blackfly specialists, and consequently the sites visited were sometimes in villages (for adult mosquitoes in cow sheds) but more usually on the banks of rivers and streams (for blackfly larvae and pupae). As it happened, the riverine habitats were the only ones to produce any Diptera as the open grassland was dry and baked in the summer sun. Day temperatures were in the upper 30s, and it was only at the high-altitude localities that Diptera were more abundant. Early morning and evening were the best times of day to collect Diptera.

 

Some 1350 specimens were collected and pinned. Over the next few months those on minutien pins will be mounted, and data labels will be printed and attached to all specimens, which will then be sorted to families.  Adrian will continue sorting and identifying the Muscidae, and Michael Ackland will continue his work with the Anthomyiidae.

 

Among other families, there were few Brachycera and few Acalyptrates. Dolichopodidae were very abundant around the streams, but the season for Empididae was clearly over and very few specimens were found. Sarcophagidae were abundant, but there were few Calliphoridae and only a moderate number of Tachinidae. In the Muscidae, genera such as Thricops, Drymeia, Phaonia, Helina, Mydaea, Coenosia, were also notably scarce or absent. One species (undescribed) of Spilogona was common at Lake Kari. Lispe species and some Limnophora were present at almost all rivers and streams and, as in 2010, Lispe tentaculata was the most abundant and widespread predaceous species of Muscidae and was observed taking adult chironomid midges as prey.

 

In a paper in 2005 (Pont, A.C., Werner, D., and Kachvoryan, E.A., A preliminary list of the Fanniidae and Muscidae (Diptera) of Armenia,  Zoology in the Middle East, 36: 73-86) Adrian noted that only 20 species of Muscidae had previously been recorded from Armenia. The list now stands at well over 100 species, and grows with each field trip.

 

This article was taken from Entom news - thanks to Adrian and Esther for content.

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Recently, a group of Scientists from the NHM (Shelley Cook, Ralph Harbach, Lorna Culverwell, Erica McAlister, Entomology; and David Bass, Zoology) and a research student from the University of Oxford (Ed Glucksman) joined forces with Unité des Virus Emergents, Marseille, Université de la Méditerranée (Gregory Moureau and Laurence Bichaud) for a cross-disciplinary collecting trip.

 

RH.JPG

 

Ralph apparently playing Crazy Golf, but he and Erica are in fact collecting adults and immatures…..

 

 

The aims of the trip, conceived by Shelley, were threefold; firstly, the Collection of voucher specimens of mosquito species present in the region for morphological and molecular identification work, and for the Collections here at the Museum. Voucher specimens simply means specimens that are collected and kept in collections for reference – in contrast to simply identifying in the field or lab and not keeping them. In total, approximately 100 mosquitoes will be processed for voucher work, which includes both morphological and molecular characterisation, and many more flies will be added as well. The molecular analysis will be for specific DNA sequences that are now widely used in molecular identification – often called DNA barcodes.  These use mitochondrial cytochrome c oxidase subunit I and II (COI and COII sequence).

 

asp.JPG

Preparing to use the aspirator - a device for sucking up insects

 

The second aim was the collection of bulk samples of adult and immature mosquitoes onto dry ice for screening for flaviviruses; 2010 saw the first two cases of dengue fever (caused by a flavivirus) in patients in metropolitan France (near Nice) with no history of travel and whom were most likely to have been infected by mosquitoes from a local population. In total, approximately 2000 samples were plated for later screening. Previous similar studies conducted by our group have shown a prevalence of novel flaviviruses of up to 10%. Any virus positives will be isolated, characterised and sequenced before publication in scientific journals..

 

sc.JPG


Shelley concentrating on numbering samples

 

 

And thirdly, together with David Bass from Zoology, the collection of a range of plant, water and insect specimens were put into liquid nitrogen followed by extraction of small RNA fractions. These will be tested via Illumina sequencing to test whether this method can detect signatures of viral infection and to compare viral biodiversity across a range of environmental samples - including in particular in association with mosquitoes and protists (single-celled organisms).

 

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David wading to collect samples - always that temptation to go a bit deeper than the length of the waders...

 

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Team photograph

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Friday April 8th
Flett Theatre

 

11:30 am - 12:30 pm


Larval morphology  of the forensically important Muscidae of Europe


Andrzej  Grzywacz
Nicolaus Copernicus University, ToruÅ„,  Poland


The Muscidae is a large  dipteran family of some 4500 species and with a cosmopolitan distribution. Many  species exhibit various degrees of synanthropy, and some are important from a  medical and veterinary point of view, like those attracted to decaying organic  matter (e.g. decomposing bodies). Housefly species on decomposed bodies, both as  larvae and adults were found in carrion experiments and death investigations.  Application of methods  of Forensic Entomology requires proper species  identification of collected material.


The morphology of immature stages in  carrion visiting houseflies is unequally studied. In some species immature  stages are not described and in the others only some stages are known. On the  second hand characters used in some keys do not allow to easy species  identification. It results in serious problems with identification of immature  houseflies in forensic cases.


During an ongoing project morphological data  concerning the immature stages of all European species of Muscidae of forensic  importance will be revised. Results will be used to prepare an identification  key for the larvae of forensically important species. For this purpose results  obtained during this visit in Natural History Museum will be essential, as also  for the future research projects concerned on larval morphology of Muscidae and  Fanniidae.

 


Contact: Vladimir Blagoderov - vlab@nhm.ac.uk