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Many of the visitors to the Manchester Museum’s Entomology store are researchers, studying various aspects of insect diversity, taxonomy and even physical properties of their colour. A group of researchers from the New Castle University (UK) is interested in what could be a real colour of butterflies and moths seen as if through the eyes of their predators, birds in particular. Here is a brief report provided by Matthew Wheelwright (Fig. 1), a postgraduate student who is involved in this research project:

Fig_01

Fig. 1. Matthew Wheelwright, a postgraduate student from the New Castle University (on the left) and Phillip Rispin, a curatorial assistant from the Manchester Museum (on the right), are sorting out lepidopteran specimens for scanning.

Colour is vitally important for many aspects of insect lives. It can help them to control their body temperature, or allow them to be recognised by members of their own species. The right body/wing colour can allow insects to blend into their environment in order to hide from predators. Another way in which colour can be used to escape predation is through giving a clear message to their potential predators that they are toxic, not edible or unpleasant tasting and should therefore be avoided. Such insects are usually brightly coloured, with a mixture of yellow/orange and black stripes and spots on their wings. This phenomenon is known as warning coloration (=aposematism). Some other species which occur in the same areas can also benefit from these warning signals by evolving to look like these not edible species; this phenomenon is known as mimicry.

Fig_02

Fig. 2. Butterflies and moths from the collection of the Manchester Museum sorted out for scanning by means of a hyperspectral camera.

The purpose of our study is two-fold. Firstly we want to find out what makes a good pattern of warning coloration and secondly to discover how closely a mimic must resemble a model having warning coloration (=aposematic model) in order to deceive predators into thinking that they are the same species. In order to do this, we need to know how these patterns look to predators (many of which have different visual systems to humans). We therefore take pictures of specimens from various collections from across the globe, including the entomology collection at the Manchester Museum (Fig. 2), using a hyperspectral camera (Fig. 3). This camera allows us to look at the exact colour spectrum of the specimens, including the amount of Ultraviolet (UV) reflected by them. The latter aspect is very important, as many predators, such as birds, can see in UV.

Fig_03

Fig. 3 A hyperspectral camera at work, scanning the Black Witch Moth (Ascalapha odorata) from the collection of the Manchester Museum.

We then used models of predator visual systems to quantitatively compare the colour and pattern of aposematic species to non-aposematic species and the patterns of mimics and models to predict how the predators could perceive them and therefore react to them. In other words, we try to see butterflies and moths through the eyes of insect predators and hope to find out whether insects that look aposematic to us (or their mimics) are seen in the same way by their predators.

Such research project would be impossible without access to museum specimens from large entomological collections such as that of the Manchester Museum. So we would like to take this opportunity to thank Dr Dmitri Logunov and Phil Rispin for their assistance and generosity with the loan of some specimens.

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Image_01

Fig. 1. The specimen of Euoniticellus intermedius (Reiche, 1849) from Honduras in the collection of the Manchester Museum. © Roisin Stanbrook.

In November 2017, the Manchester Museum acquired a specimen of a very interesting dung beetle – Euoniticellus intermedius (Reiche, 1849) (see Fig. 1) – collected from Honduras by Roisin Stanbrook, a young researcher from the Metropolitan University of Manchester who studies the ecology of dung beetles in Central Africa (see here for her interview). In Honduras, Roisin was running a field course for a group of British students, when she came across this beetle which she was familiar with from her fieldwork in Kenya. What a surprise! Below is a brief account of how this dung beetle species appeared in Central America.

E. intermedius is also known as the Intermediate Sandy Dung Beetle. It is a medium sized (6.5-9.5 cm long) species of the burrowing dung beetles that build brood chambers in the soil beneath a dung pat and supply them with dung as food for their larvae. Although this beetle is native to Africa, now it has a worldwide (=cosmopolitan) distribution because the species was intentionally introduced to many countries such as Australia, New Caledonia, Hawaii, Puerto Rico and the USA, as a biological control to decrease the dung accumulation caused by cattle and the proliferation of pest flies.

Following its introduction to the USA (in California apparently in 1978, in Texas in 1979, and in Georgia in 1984), E. intermedius started a rapid range expansion across the south of the USA, up to Florida, and Central America, with an estimated speed of about 50 km or more per year. In 1992, it was first recorded in Mexico (the site Mapimí), then it reached Guatemala in 2002, Nicaragua in 2007 and Costa Rica in 2008; in 2015, the beetle was already recorded from the border of Panama (see Maps below).

Maps

Maps. A – Dispersal of Euoniticellus intermedius in Mexico after its introduction in the USA (after de Oca & Halffter, 1998). B – Further dispersal of E. intermedius from southern Mexico across the Isthmus of Panama (after Solis et al., 2015).

 

The beetle has been particularly successful at colonizing arid zones, where the number of native burrowing dung beetles was rather low. For instance, at some places in Mexico, 96% of the individuals (and a great proportion of biomass) corresponded to two invasive dung beetles: E. intermedius and the Gazelle Scarab – Digitonthophagus gazella (Fabricius, 1787), another widely introduced species of dung beetles (see here for further information about it).

But why has the Intermediate Sandy Dung Beetle been so successful in colonizing Americas? There are two main reasons. First, this species has certain biological properties that help its rapid expansion: (1) it is a highly prolific species that can have two or more broods of offspring per year; (2) it is an eurytopic species that can live in a wide variety of habitats and tolerate a wide range of environmental conditions; and (3) it has a preference for bovine dung, which is both very abundant in cattle-farmed areas and nutritionally rich, but yet poorly/not utilized by native Central American species.

Second, quite favourable ecological conditions for E. intermedius (and for D. gazella) have been created by the human activity in Central America: viz., (1) deforestation leading to the creation of open, sunny and dry habitats (=pastures) to which this African species is well-adapted; (2) increase in cattle breeding resulted in the production of excessive amounts of dung (=food resource for the beetle); and (3) the inability of native dung beetles to properly utilize cattle dung, which actually means that there was no competition with native species for this food resource.

Although the ecological impact of E. intermedius on native dung beetles is poorly understood yet, those from the guild of burrowing (=paracoprid) dung beetles are to be affected for sure. Soon we’ll be able to see if this beetle is able to colonize South America and what its presence in the areas already invaded could do to the native biota.

Here and here you can find further information about E. intermedius.

Further reading:

Oca de, E.M. & Halffter, G. (1998) Invasion of Mexico by two dung beetles previously introduced into the United States.- Studies on Neotropical Fauna and Environment, 33(1): 37-45; http://dx.doi.org/10.1076/snfe.33.1.37.2174

Chinese_Mitten_Crab

The Manchester Museum’s specimen of the male Chinese Mitten Crab (Eriocheir sinensis), collected from Ribble Estuary, Lancashire, in 2007.

The Chinese Mitten Crab (Eriocheir sinensis) is an accidentally imported species in the North Sea, which is considered one of the World’s 100 worst invasive species. The crab first appeared in northern Germany in 1912. It was unintentionally brought from China, apparently as a stowaway in the ballast tanks of cargo ships. Since 1912, the crab has dramatically spread over northern Europe. It was first recorded from Thames River in 1935. Now it is also established in the Rivers Humber, Medway, Tyne, Wharfe and Ouse, increasing its range throughout England and Wales by several tens of kilometres a year. See here about Mitten Crab recording project in the UK.

This crab lives both in fresh and salt waters. In autumn, adult crabs undertake a mass migration from freshwaters to river estuaries for reproduction, crossing long distances over dry land. In October-December, crabs mate, females produce eggs and move deeper to the sea where eggs and several larval stages develop. Young crabs migrate back to freshwaters. They reach sexual maturity in three years and then migrate back to the sea to reproduce.

These crabs can cause serious ecological damage. As adults usually burrow in muddy riverbanks, they can damage them, modify natural habitats and compete with native species. There are no effective means to control this crab species. In Germany, special traps were used during mass crab migrations, but they proved to be ineffective. However, the crabs are edible and even considered delicacy in China. Thus, maybe these crabs should just ‘be eaten’ to stop them damaging British wildlife (see more about this)?

In the vide below, Dr Malcolm Greenhalgh, the author of the notable book on the British Freshwater Life is talking about the Chinese Mitten Crab and the first male specimen collected from North-West.

In late January 2017, Ms Eleanor Smith of Wilmslow (Cheshire, UK) visited the Manchester Museum and brought a medium-sized spider (see Fig. 1) that was found alive in a bunch of bananas, in a supermarket (Lidl) near Wilmslow. As she was told, the bananas on which the spider was found were delivered from Colombia. Unfortunately, the spider was already dead because Eleanor had kept the jar with the spider in a fridge; far too cold for such a tropical creature. The specimen was found to belong to what is commonly known as ‘Banana Spiders’. It was a mature female that was identified as Sadala sp. in the family Sparassidae, huntsman spiders. The specimen is now deposited in the Manchester Museum’s spider collection (accession number G7585.1).

Fig_01_Sparassidae_Colombia
Fig.1Female of Sadala sp. (Sparassidae) imported to the UK from Colombia; the Manchester Museum (G7585.1).

Spiders that are incidentally imported with bananas are commonly called ‘Banana Spiders’. However, this common English name is rather misleading, as it is used for quite a number of different spider groups.

In North America, this name can be applied to Golden Orb-web Spiders (Nephila species, family Nephilidae – most commonly Nephila clavipes); see also here and here. The reasons why this species is called ‘Banana Spider’ remain unclear, for there is no obvious connection between the spider and bananas – could it be because of the banana-shaped abdomen of rather large females? By the way, some Nephila species are edible and even considered a delicacy by indigenous people in New Caledonia and Australia, for instance, Nephila edulis (and here).

The wandering spiders (family Ctenidae) are regularly called ‘Banana Spiders’ as well (see Vetter et al., 2014). Some of them have even acquired a very bad media-reputation as deadly venomous species: for instance, the Brazilian Wandering Spider (Phoneutria fera). Alas, most of online media reports – for instance, MailOne(24 June 2015) or Independent(21 September 2016) – cannot be taken seriously, as they fail to even provide a correct identification of the spiders found on bananas.

In reality, to date, there has been only one published record of the Brazilian Wandering Spider as being imported to Europe (Germany) in 1950s, but yet the identification of that specimen causes doubts. The majority of existing records of “Brazilian Wandering Spiders”, both from Europe and from North America, are likely to belong either to the harmless Central American spider genus, Cupiennius (Ctenidae), or (much rarer!) to other Phoneutria species – most commonly, to Phoneutria boliviensis, a medically important wandering spider from Central America.

By far the most common spider group being imported with bananas is the pantropical huntsman spiders (family Sparassidae), also called ‘Banana Spiders’. In total, 13 species of huntsman spiders have been identified of those imported with bananas and other international goods to Europe. At least five species of huntsman spiders have been reported as being imported with bananas to the UK (Browning, 1954; Wilson, 2011): Barylestis occidentalis, Barylestis scutatus, Barylestis variatus (all from Africa), Heteropoda venatoria (from SE Asia, but now pantropical) and Olios sanctivincenti (from Asia). The commonest of them is Heteropoda venatoria, which is even established indoor in some regions of southern Europe (see Fig. 2). Yet, a real number of imported huntsman spiders might be much higher; Sadala sp. which was mentioned above (Fig. 1) is a new record from this group.

Fig_02_Heteropoda ventoria

Fig.2. Female (top) and male (bottom) of Heteropoda venatoria (Sparassidae);the Manchester Museum.

The spider collection of the Manchester Museum contains a number of samples of huntsman spiders collected from bananas in Manchester and its vicinities; for instance, from the Manchester Market Street in June 1912 or April 1931 (Fig. 3).

Fig_03_Banana Spiders

Several spider species that were obtained from the Manchester Open Air Market from imported bananas; the Manchester Museum.

Overall, a number of alien spider species that are imported with bananas and other international cargo to Europe or North America is rather high. For instance, Nentwig (2015) listed 184 species that have been imported to Europe over the last 200 years; of them 47 species have established there in and around human buildings. Vetter et al. (2014) identified 135 spider species imported to the USA in seven years (between 2006 and 2010). Although in the past banana or other fruit shipments were the main pathway of introduction to Europe, today potted plants and apparently container shipments in general are more important. It is suspected that due to the increasing international trade volume and climate change, in the next decades at least one new spider species will be introduced to Europe and established there annually.

Further reading

Nentwig W. (2015) Introduction, establishment rate, pathways and impact of spiders alien to Europe – Biol Invasions, 17: 2757–2778. DOI 10.1007/s10530-015-0912-5

Nentwig W. and Kobelt M. (2010) Spiders (Araneae). Chapter 7.3 – BioRisk, 4(1): 131–147. doi: 10.3897/biorisk.4.48

Vetter R.S., Crawford R.L., and Buckle D.J. (2014) spiders (Araneae) found in bananas and other international cargo submitted to North American arachnologists for identification – Journal of Medical Entomology, 51(6): 1136–1143. URL: http://www.bioone.org/doi/full/10.1603/ME14037

Wilson R. (2011) Some tropical spiders recorded in Leeds, West Yorkshire and a review of non-native taxa recorded in the UK – The Newsletters of the British Arachnological Society, No.120: 1–5.

Macrodontia_dejeani_MM

Male (left) and female (right) of the longhorn beetle Macrodontia dejeani Gory, 1839 from Colombia; the Manchester Museum’s Entomology collection.

This species of longhorn beetles (family Cerambycidae) is rare in collections. It has a claimed range from Costa Rica to Ecuador and Peru but its heartland is Colombia. If 70 years of civil war and drug wars in Colombia is beginning to settle down, then perhaps more collectors will run collecting night lights there and more dejeani will appear.  This beetle is named after General Pierre Dejean, a prominent figure in Napoleon army and a notable entomologist at the same time. The story of this eccentric man is told by Martin Laithwaite (Huddersfield, West Yorkshire).

Pierre Francois Marie Auguste Dejean (1780-1845)

Pierre “Auguste” Dejean was a soldier of fortune during the Napoleonic Wars; he became Colonel of the 11th Dragoons in 1807, General of Brigade in 1811, General of Division in 1814, served eight years as head of the Administration of War under Napoleon and was one of the Emperor’s aide-de-camps at the Battle of Waterloo. A prominent figure during the Empire, he is mentioned in Marshall MacDonald’s and Baron de Marbot’s memoirs.

He is also well-known for his five volume work on beetles and was one of the most important entomologists of his time. The Annals of the Entomological Society of France, vol. 2, p.502, 1845 relates that General Dejean, commanding the French army at the battle of Alcanizas was awaiting the attack of the enemy and noticed a rare specimen on a nearby flower. Jumping from his horse, he captured the click beetle, a Cebrio ustulatus, fastened it to a piece of cork, which he always carried under his chapeau for this reason, remounted his horse and won the battle.

The account was written by his private curator M. Boisduval “Before the battle of Alcanizas, which Dejean won after a long-contested fight, taking a great number of prisoners, when the enemy had just appeared and he was prepared to give the signal of attack. Dejean, at the border of a brook caught sight of a Cebrio ustulatus on a flower.  He immediately dismounted, pinned the insect, applied it to the inside of his helmet which, for this purpose, was always supplied with pieces of cork, and started the battle.  After this, Dejean’s helmet was terribly maltreated from cartouche fire; but, fortunately, he refound his precious Cebrio intact on its piece of cork.”

Most of the soldiers in his regiment learned to collect insects. Each carried a small vial of alcohol in which to place the insects he collected. It was claimed that even the enemy knew of Dejean’s eccentricity – those who found dead soldiers on the field having with them a little bottle containing insects in alcohol always sent the bottle to Dejean, regardless of who won the battle.

He amassed vast collections of beetles and listed 22,399 species in his cabinets in 1837—at the time, the greatest collection of coleoptera in the world. In 1802, he began publishing a catalogue of his collection, including 22,000 species names. Dejean was an opponent of the Principle of Priority in nomenclature. “I have made it a rule always to preserve the name most generally used, and not the oldest one; because it seems to me that general usage should always be followed and that it is harmful to change what has already been established”. Dejean acted accordingly and often introduced received popular usage names, given by himself to replace those already published by other authors; his names became invalid. However he is the authority for the family names of attractive popular well-studied beetle genera such as Batocera (family Cerambycidae) and Chrysochroa (family Buprestidae).

Dejean was president of the Société Entomologique de France in 1840. In 1834, he was elected a foreign member of the Royal Swedish Academy of Sciences. In later life, Dejean financed a number of collecting expeditions (particularly to what is now Panama and Colombia) and much of what he received was new to science.

Copris_lunaris

Nesting by the Horned Dung Beetle (Copris lunaris): 1 – Initial stage, male (left) and female (right) working the ‘dung cake’; 2 – Female alone, making brood-balls of the ‘cake’ for laying eggs. Illustration by V.A. Timokhanov (Almaty, Kazakhstan).

Waste disposal is a growing problem for any industrialized nation. The UK alone generates about 100 million tonnes of waste each year, the majority of which is still being disposed of through landfill. The present story is about dung beetles or scarabs (family Scarabaeidae) that are involved in processing and decomposing dung.

On average, about 40% of the food intake of mammals is either excreted as urine or passed out of the body as faeces. This waste is decomposed and returned to the soil by insects that use dung as food for themselves and for their larvae, thereby preventing it from building up. How this is accomplished is best known for cattle dung.

A cow’s fresh dung pat is colonized by a succession of dung-breeding insects, numbering several dozen species and often exceeding 1000 individual insects. A total of 275 species has been reported to occur in cattle dung in Britain. The majority of them are dung beetles that feed directly on dung. There are three main ecological groups of dung beetles. First, small-sized beetles (Aphodius species) usually feed in the main dung mass. Others, like the horned dung beetle, dig burrows beneath the pat and pack pieces of dung into them for feeding their larvae (see figure above). The third group includes beetles that make spherical dung balls, roll them away and bury them intact in shallow burrows. The Sacred Scarab is the most famous of the rollers. As well as dung beetles, the pat is colonized by dung-feeding fly maggots, predatory beetles which feed on eggs and larvae of other insects, small parasitic wasps, fungus-eating insects and mites, etc. At the advanced stage of degradation, soil invertebrates, including earthworms, begin to move into the dung pat. The natural rate of dung degradation depends on temperature, humidity, habitat and season of deposition. In Britain, the complete natural disappearance of a dung pat is achieved in two to three months.

Sacred_Scarab_Stockholm

Sculpture of the Sacred Scarab in the Natural History Museum in Stokholm, Sweden. © Dmitri Logunov, Manchester Museum.

It is known that each cow produces an average of 12 dung pats per day, or over 9000 kg of solid waste per year. It is estimated that each year approximately 200 million tonnes of waste are produced by livestock in England and Wales, and about 900 million tonnes in the USA. About third of this is recycled by dung beetles. In the USA alone, the annual economic value of this service is at least $380 million.

Unfortunately, the activity of dung beetles is severely disrupted by current agricultural practices, such as the treatment of livestock with persistent anti-helminth drugs given to kill parasitic worms or helminths. Residues of these drugs can persist in the dung and are lethal to the beetles. As a result, the dung pats of animals treated with anti-helminthes remain biologically undegraded for months, fouling available grazing area. If left unprocessed, livestock wastes may present a health risk to humans, because they can contain some pathogenic microorganisms.

By recycling the nutrients locked up in dead organic materials such as dung, insects make these nutrients available to new life. As recyclers, they do an indispensable job for our planet. Without organisms breaking down dead organic materials and recycling nutrients in the wild, as well as in gardens and on farms, the planet would soon be piled deep with the waste products of its inhabitants, and potential spread of diseases would be unavoidable. Whether we like it or not, our own existence directly depends on insects and their ecological services. As M. Telfer (2004) put it: “Not everyone welcomes having ‘creepy-crawlies’ around but we should be grateful for what they do.”

In the following video, our special guest, Ms Roisin Stanbrook from the Manchester Metropolitan University, is taking about the ecological role of dung beetles in Kenya.

The presented story is based on: Logunov D.V. 2010. Nature’s recycling squad. Biological Sciences Review, 22(3): 22-25.

Further reading:

Berenbaum, M.R. (1995). Bugs in the system. Insects and their impact on human affairs. Helix Books.

Waldbauer, G. (2003). What good are bugs? Cambridge-London: Harvard University Press.

Harelquin_Ladybird_Collection

The Manchester Museum’s collection of Harlequin Ladybirds recently acquired under the ongoing museum project ‘Thematic collecting’.

Recently, the Manchester Museum’s Entomology Department acquired some specimens of the Harlequin Ladybird, an invasive beetle species that appeared in Britain (Essex) in 2004 only, but is now a widespread and even dominant species of ladybirds in the UK.

 

Harlequin Ladybird – Harmonia axyridis (Pallas, 1773) (Coleoptera: Coccinellidae) – is a beetle species in the same family with the Seven-spot and Two-spot Ladybirds, both being considered gardener’s best friends as natural enemies of aphids and other garden pests. Harlequin Ladybird was deliberately introduced from east parts of Eurasia, where it is a native species, to many places of continental Europe as a biological agent to control aphids (=greenflies) and scale insects. As Harlequin Ladybird has excellent dispersal abilities (by means of flight), it was just the matter of time until it could have reached the British Isles.

A number of factors have contributed to the successful establishment and dominance of this ladybird species in the UK, particularly, its high reproductive capacity and ability to live in most available habitats. Harlequin Ladybird is also a voracious predator that can feed on other ladybird species.

The UK Ladybird Survey is a citizen science initiative that was launched in 2005, right after the first records of Harlequin Ladybird in Britain had been done. This programme is aimed at encouraging people across Britain to track the spread of Harlequin Ladybird (and other ladybirds) across the UK and submit their records online. Based on this survey, it is clear that by 2014 the Harlequin Ladybird has extended its range by almost half of the country. A decline of seven native ladybird species, which is correlated with the arrival of Harmonia axyridis, has also been demonstrated.

How to control this species and its spread in the UK is a bit unclear. Harlequin Ladybird produces a special, aggregation pheromone to attract other individuals to overwinterwing habitats. It has been proposed to use this pheromone within a network of traps in order to physically withdraw Harlequin Ladybirds from the environment. However, the cost of managing such traps is potentially too high to be feasible. The use of natural enemies of Harmonia axyridis, such as the ectoparasitic mite (Coccipolipus hippodamiae) that is capable to induce sterility in females of Harlequin Ladybirds, has also been considered, but alas with no practical applications so far. Therefore, this species is likely to be staying in the British Isles, apparently becoming another ‘native’ ladybird species with which we are to live (as it already happened with many other insect, crustacean and mollusc species).

Harelquin_Ladybird_Map

The occurrence of Harlequin Ladybirds in Britain from 2004 to 2014 (one dot is equal to 10-km square), after Roy & Brown (2015).

In the following interview, Don Stenhouse, the Curator of Natural Sciences at the Bolton Museum, will share with us his own experience in studying the Harlequin Ladybird.

A full story of the Harlequin Ladybird in the UK can be found in the following paper:

Roy H.E. and P.M.J. Brown (2015), ‘Ten years of invasion: Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in Britain’ – Ecological Entomology, 40(4): 336–348; online at: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4584496/