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MYRMECOLOGY LAB

Dip. Biologia Evolutiva e Funzionale, Università di Parma www.myrmecologylab.wordpress.com

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The AISASP Student Meeting

The AISASP - Italian Section of the IUSSI - aims to promote the knowledge and ideas exchange among researchers of the fascinating and complex universe of social insects.

Within this mission, the Associates' Council proposed that, beside the national and international AISASP-IUSSI congresses, there should be a meeting completely and exclusively dedicated to students.

The main aim is, in first place, to provide them an opportunity to refine the communication of their own scientific results. Moreover, this kind of occasions could represent a level of communication quite different from that of usual congresses. Indeed, albeit being an important opportunity of scientific and cultural exchange, typical congresses are forums for discussing, mainly, data interpretations and conclusions. Thus, methodological issues and practical solutions, the bases of the daily work for young researchers, are often poorly discussed of not properly addressed.

Therefore, this is the mission of the AISASP Student Meeting: a meeting organized by "students" for "students", providing a workshop for undergraduates,

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The final aim of the AISASP Student Meeting is to give support to the exchanges of ideas, projects and scientific actions since the beginning of the AISASP young scientists career, with the hope and the ambition to become a traditional event promoting a "School" for the study of social insects

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Organizers welcome

Parma, 2nd March 2012

Welcome to the al 2nd AISASP Student Meeting!

For the second year we are newly here, organizing another exciting day of young scientist workshop.

Since the good success of the past edition of the Meeting, we are happy to have the opportunity to meet each other again in the AISASP context and to give continuity to this action.

Once again, everything has been possible thanks to you, young contributing authors of the meeting, and we hope this will be another day of good science. We wish to thank also the host Institutions, the University of Parma, for the given support and facilities.

We finally wish to give a special thank to our invited speakers, Rob Dunn and Manuela Giovanetti, who enthusiastically joined our initiative and accepted to introduce the day.

Have a nice Meeting!

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How to reach us

From the train station:

From the main square outside the train station take the bus 7, 14 or 21 with the direction "Università Sud". Once the bus entered the main entrance on Langhirano street, get off form the bus at the main stop (in front of the newsstand). Hold the Engineering Faculty to your back, the entrance of the Centro Congressi Santa Elisabetta is 50 mt straight ahead.

From the highway:

A1:

-Exit to Parma nord and follow for Milano-Piacenza. Exit to Langhirano-Campus and go ahead for 7 km unitl the exit Campus (on the whole 15 km). Once in the Campus area go through the main street and turn left at the newsstand. The Centro Congressi Santa Elisabetta is 50 mt straight ahead

A15:

-Exit to Parma ovest and follow for Parma. After the hotel "Parma-Congressi" on the left, get north unitl the exit Langhirano-Campus. Drive for 7 km until the exit Campus. Once in the Campus area go through the main street and turn left at the newsstand. The Centro Congressi Santa Elisabetta is 50 mt straight ahead.

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09.30 – 09.45 Registration and Welcome

09.45 – 10.45 Invited Speaker: Rob Dunn

North Carolina State University

THE FUTURE OF ANTS IN A WARMER, MORE URBAN WORLD - LESSONS FROM GLOBAL COLLABORATIONS, LARGE-SCALE EXPERIMENTS, AND CHILDREN

10.45 – 11.45 Invited Speaker: Manuela Giovanetti

Università Federico II di Napoli

EVOLUTION OF SOCIALITY IN CERCERIS WASPS: FROM ANECDOTES TO DATA

11.45 – 12.00 Coffe Break

12.00 – 12.20 Federico Cappa

Università degli Studi di Firenze

POLISTES DOMINULUS-XENOS VESPARUM: WHEN THE ROLE OF THE PARASITE DEPENDS ON THE SEX OF THE HOST

12.20 – 12.40 Stefania Meconcelli

Università degli Studi di Torino

STUDY ON THE MODALITY OF TRANSMISSION OF THE MITE VARROA DESTRUCTOR AMONG COLONIES OF

APIS MELLIFERA 12.40 – 13.00 Fiorenza Spotti

Università degli Studi di Parma

ANTS GO TO SCHOOL: "THE SCHOOL OF ANTS" PROJECT LANDS IN ITALY

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14.00 – 14.20 Iacopo Petrocelli

Università degli Studi di Firenze

UN D E R S TA N D I N G E C O L O G I C A L A N D S O C I A L C O N S T R A I N T S D R I V I N G T H E E V O L U T I O N O F PHENOTYPE: A WIDE COMPARATIVE STUDY IN

POLISTES PAPER WASPS 14.20 – 14.40 Pierpaola Piras

Università degli Studi di Modena e Reggio Emilia

CONTROL OF VARROA DESTRUCTOR ON DOMESTIC HONEYBEES IN SARDINIA: FIELD TRIALS WITH PRODUCTS BASE ON THYMOL AND FORMIC ACID

14.40 – 15.00 Simone Tosi

Università degli Studi di Bologna

IN F L U E N C E O F S T R E S S O R S O N HONEYBEES: PROPOSALS FOR IMPROVEMENT OF OFFICIAL RISK ASSESSMENT GUIDELINES

15.00 – 15.20 Giorgia Lombardo

Università degli Studi di Parma

CONTINUOUS OCCURRENCE OF INTRA-INDIVIDUAL CHROMOSOME REARRANGEMENTS IN THE PEACH POTATO APHID MYZUS PERSICAE (HEMIPTERA: APHIDIDAE)

15.20 – 15.40 Giovanni Lazzari

Università degli Studi di Parma

ECOETHOLOGY OF THE MULTITROPHIC RELATIONS A M O N G A N T S, S A P-S U C K I N G I N S E C T S A N D PREDATORY BEETLES: A CASE STUDY IN WHICH

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16.00 – 16.10 Ginevra Cusseau

Università degli Studi di Firenze

DEFENCE REACTIONS OF APIS MELLIFERA LIGUSTICA AGAINST ATTACKS FROM THE EUROPEAN HORNET

VESPA CRABRO 16.10 – 16.20 Martina Mueller

Università degli Studi di Bologna

FACULTATIVE PARTHENOGENESIS IN TERMITES: AN A N A LY S I S W I T H M O L E C U L A R M A R K E R S I N

RE T I C U L I T E R M E S U R B I S A N D R . L U C I F U G U S

(ISOPTERA,RHINOTERMITIDAE) 16.20 – 16.30 Maria Cipollini

Università degli Studi di Firenze

A QUANTITATIVE THRESHOLD FOR NEST-MATE RECOGNITION IN HONEYBEE APIS MELLIFERA

16.30 – 16.40 Rachele Nieri

Università degli Studi di Firenze

AD U LT-I M M AT U R E B R O O D I N T E R A C T I O N S: A COMMUNICATION CHANNEL TO BE EXPLOITED BY THE SOCIAL PARASITE P. SULCIFER

16.40 – 16.50 Ilaria Protti

Università degli Studi di Firenze

MODIFICATION OF THE CUTICOLAR CHEMICAL PROFILE OF APIS MELLIFERA INDUCED BY THE MITE VARROA DESTRUCTOR

16.50 – 17.00 Silvia Bedetti

Università degli Studi di Parma

THE ANT FAUNA IN GRAN PARADISO NATIONAL PARK: ANALYSIS OF BIODIVERSITY AND OF COMMUNITIY STRUCTURE

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17.00-17.10 Patrizia Cherubini

Università degli Studi di Parma

THE ANT FAUNA IN GRAN PARADISO NATIONAL PARK: ANALYSIS OF ACTIVITY RATES

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INVITED SPEAKER

Rob Dunn

North Carolina State University

THE FUTURE OF ANTS IN A WARMER, MORE URBAN WORLD

-LESSONS FROM GLOBAL COLLABORATIONS, LARGE-SCALE EXPERIMENTS, AND CHILDREN

Ants live around humans nearly everywhere we live. The live in our kitchens, backyards, forests, grasslands and nearly everywhere else. The question is how these ants will change in the future, as the world becomes warmer and more urban. In my group we have used a combination of global collaborations, good old fashioned natural history, and molecular genetics and large-scale experiments to understand the history and future of ants in light of our changing world. I will discuss our results but also the ways in which we are still so naive about the living world, whether ants,crickets, bacteria or nearly anything else, that often major discoveries can be made simply by looking around, major discoveries, of course, that change both our understanding of the species that live around us now and those that will live around us in the future.

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INVITED SPEAKER

Manuela Giovanetti

Università Federico II di Napoli

EVOLUTION OF SOCIALITY IN CERCERIS WASPS: FROM ANECDOTES TO DATA

Cerceris is the widest genus in the family Crabronidae.

More than 850 species have been described, recorded in all continents and in different climatic conditions. The most interesting feature of this genus is the fact that females may express different levels of tolerance towards conspecifics, leading to cases of co-occupancy, or even sharing, of the same nest. Some cases of true eusociality have been reported. The genus may then be a reach container where to investigate the first steps toward the evolution of social behaviours. Ground-nesting wasps are known to be mostly solitary, digging a nest made of a main tunnel. Often there are secondary tunnels that lead to one/some pedotrophic cells. Cells are provisioned with a variable number of prey, hunted by the females during day-time in the vicinity of the nesting site. The fact that sometimes an observer may see more than one female coming out of the same nest induced a special kind of interest on some fossorial species, especially pointing to the evolution of cooperative behaviours. Unfortunately, there is an important limit in the study of ground-nesting wasps: the majority of these insects do not accept artificial environments, as the ones usually created to make observations under controlled conditions. The available data lie in what an observer can record in the field, while waiting at the nesting site for females coming

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back from provisioning trips. I will introduce you to this fascinating genus, to the wide amount of literature that may be recalled and to the difficulties in approaching it for review purposes, to the results of some field studies on tropical and temperate species I finally managed to deal with.

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Federico Cappa

Università degli Studi di Firenze

POLISTES DOMINULUS-XENOS VESPARUM: WHEN THE ROLE OF THE PARASITE DEPENDS ON THE SEX OF THE HOST

The parasite Xenos vesparum affects both the behaviour and the physical traits of its host, the social wasp Polistes

dominulus. Female wasps, if parasitized, do not perform

any social tasks and desert the colony to gather at specific sites, where the parasite mates. Among the morphophysiological changes induced by the parasite, the most dramatic is the castration of the female hosts (Beani et al., 2011). The parasite belongs to the order Strepsiptera entirely constituted by parasitic castrators. Due to this peculiarity all the strepsiterans have been defined as parasitoids rather than parasites, because of the reproductive death of their hosts. In a 2-year study carried out both in the field and in lab we observed the occurrence of parasitized males of P. dominulus in natural nuptial arenas and tested the sexual behaviour of such allegedly castrated males in experimental trials. Furthermore, we investigated the ultrastructure of the reproductive apparatus of both parasitized and healthy males in order assess possible alterations due to the presence of the parasite. We found no significant differences in either the sexual activity or the reproductive apparatus structure between parasitized males and healthy controls. Our results lead us to conclude that while the definition of X. vesparum as a parasitoid may be correct when referring to female hosts, which are always irreparably castrated, it is not so adequate when applied to male hosts. In this case the definition of X.

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vesparum as a parasite seems more appropriate, given

the evidence that stylopized males neither lose their sexual behaviour nor is their reproductive apparatus compromised by the parasite.

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Stefania Meconcelli

Università degli Studi di Torino

STUDY ON THE MODALITY OF TRANSMISSION OF THE MITE

VARROA DESTRUCTOR AMONG COLONIES OF APIS MELLIFERA Varroa destructor is a mite that parasitize honeybee

colonies. The mite feeds itself of larvae's and adult bee's hemolimph causing damages both at individual and at colony level. The varroa prefers bees with a certain task. Particularly in phoretic phase the mite transfers itself on nurse bees so that they can be transported in other cells where the mite's reproduction can take place. In this study we hypothesize that in a state of high infeastation level, the best survival and reproduction strategy is to leave the colony and attack a new hive. Therefore varroa's choice should no longer be nurse bees, but foragers, who would have the function of dispersal outside the hive. Moreover during periods of low availability of resources there often occurs raidings of colonies by foragers bees of neighbouring hives. In such a situation varroa's best choice could be to move on an heterocolonial forager bee and ensure in this way its transfer in another colony. In order to verify our hypothesis, we tested phoretic mites from hives with different infestation rates, in two different choice tests: choice between nurse bee and homocolonial forager bee; choice between homocolonial forager bee and heterocolonial forager bee. We then performed chemical analyses of the epicuticular compounds of nurse bees and forager bees from colonies with three different infestation rates. We wanted to assess the presence of any difference in the chemical profile potentially

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responsible of the differential choice of the mite. Our results show that, at low infestation rates, mites stay within the hive and promote their reproduction by riding nurses that they recognize from foragers by different chemical cuticular signature. When infestation level increases, the signature of nurses and foragers overlaps promoting mites departure from exploited hives.

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Fiorenza Spotti

Università degli Studi di Parma

ANTS GO TO SCHOOL: "THE SCHOOL OF ANTS" PROJECT LANDS IN ITALY

The School of Ants project is a citizen-scientist driven study of the urban ant-fauna (Hymenoptera, Formicidae): it meets the requirement to learn more about the distribution of ant species that live in urban areas, particularly around homes and schools. Headed by North Carolina State University researchers, this project wants to documented relative abundance and species richness of ants not only in North Carolina, but across the USA and, little by little as the project grows, all over the world. The collected samples can help to improve the knowledge about local biodiversity, native and introduced species in cities and to assess the effects of climate changes on urban areas. So the first aim of this research is collecting ants in schoolyards and in their surroundings, using a standardized protocol in order to get a detailed map of ant communities that live just outside our doorstep. The ultimate goal of the project is to teach the meaning and the importance of the word “biodiversity” to students, through the monitoring of the environment around them. To this purpose, ants are a very useful model of animal biodiversity, because they are extremely widespread and easy to observe. The Myrmecology Lab (Dipartimento di Biologia Evolutiva e Funzionale, Università degli Studi di Parma) is the Italian partner of “The School of Ants” project. In autumn 2011, we went to some of primary and secondary schools in Parma (Italy) to sample ants. The sampling protocol

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consisted of placing “Pecan Sandies” baits outdoors in green spaces (lawns, gardens, woods) and paved places (asphalt, concrete, cobblestone) for one hour on a warm day, in order to see what and how many ants discovered the baits in this time frame. The results from this experience allowed to outline a preliminary picture of ant-fauna community structure in sampling areas; obviously, we have planned to repeat samplings in the same sites in spring and summer 2012, when temperature rises, because we need more data to better understand the mechanisms leading to structure in ant assemblages.

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Iacopo Petrocelli

Università degli Studi di Firenze

UNDERSTANDING ECOLOGICAL AND SOCIAL CONSTRAINTS D R I V I N G T H E E V O L U T I O N O F P H E N O T Y P E: A W I D E COMPARATIVE STUDY IN POLISTES PAPER WASPS

Given the centrality of chemical communication in social insects, there are many selective pressures acting on morphofunctional traits that mediate chemical pheromones. Usually much wider is a secreting surface, the greater will be its functionality. On the last gastral sternite of Polistes females there is an important exocrine surface secreting chemical pheromones, named Van der Vecht’s organ, that is involved in rank and nestmate recognition, preventing the workers from direct reproduction. Furthermore Van der Vecht’s organ is implied in the dynamics of usurpation and exploitations of host colonies by Polistes social parasites. Here we carry out a morphometric comparison within seven species of European Polistes, including three social parasites as a sort of evolutionary probe to understand the ecological and social constraints affecting the size of this exocrine area. Our findings demonstrate that this secretory abdominal area has a great plasticity in Polistes paper wasps, being generally larger in foundresses than in workers. Further, Polistes social parasites which perform both a rapid chemical mimicry with the host and an intense abdominal stroking behaviour, i. e. P. sulcifer and

P. semenowi, also show a larger Van der Vecht’s organ

than their hosts; on the contrary in P. atrimandibularis this abdominal organ has regressed, according with the fact that no abdominal stroking is performed during

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usurpation and that chemical mimicry with the host is slow. Strong social and ecological constraints, imposed by the need to maintain or usurp the dominance status, may have led to this evolutionary pattern. Therefore this findings provide a real evidence of morphological castes in at least two of the European Polistes species.

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Pierpaola Mereu Piras¹, Ignazio Floris², Lara Maistrello¹

1Universitá degli Studi di Modena - Reggio Emilia

2Università degli Studi di Sassari

CONTROL OF VARROA DESTRUCTOR ON DOMESTIC HONEYBEES IN SARDINIA: FIELD TRIALS WITH PRODUCTS BASE ON THYMOL AND FORMIC ACID

Honeybees, like all living organisms, are subject to the attack from pests, pathogens and predators that undermine them at every stage of development, and that may pose a threat to the products of the hive. The mite

Varroa destructor, officially reported in Sardinia for the

first time in June 1983, is responsible for the high mortality of bees occurred in this region in the last 30. From July to October 2011 a field trial was conducted to test the efficacy of two different acaricides, the well known Apiguard (based on thymol) and a new formulation based on formic acid, Biotab, currently produced and marketed in South America. 15 beehives from 10 combs, homogeneous for the number of adult bees, brood and degree of infestation by V. destructor, were used, dividing them into 3 experimental groups of 5 hives each, which were periodically monitored for the number of fallen mites and level of adult and larval infestation.. Starting from an initial weekly mite fall of about 200, the number increased to 500 and 400 respectively in Apiguard and Biotab groups during the week of treatment, and fell to 50 and almost 0 one week later, whereas in the control group the weekly mite fall level remained 200. These results are confirmed also by the level of larval infestation, which in Apiguard went from an average of 7.0% to 2.1% with a

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percentage reduction of 70%, while in adults the reduction was about 81% with average reduction for the whole of 75,5%. In the case of the formic acid treatment the effective average reduction was close to 100%, whit a reduction of adult bees infestation from of 7,4% to 1,4%,. In the control group there was an increase in the mite infestation. These results look promising in the perspective to increase the range of products to control

V. destructor in Mediterranean environments. However,

more work should be done to refine the timing and modalities of treatment, moderating its dose and duration, in order to mitigate possible negative effects on brood and, in some cases, on the queen bees.

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Simone Tosi1, Piotr Medrzycki2

1Università degli Studi di Bologna

2CRA-Apicoltura - Bologna

INFLUENCE OF STRESSORS ON HONEYBEES: PROPOSALS FOR IMPROVEMENT OF OFFICIAL RISK ASSESSMENT GUIDELINES

The risk assessment of pesticides on honey bees necessary to the registration of pesticides requires the application of official detailed protocols (EPPO guidelines). The test conditions described in these protocols must be respected properly in order to obtain valid results. Nevertheless, toxicity tests carried out by different laboratories often give different results. These differences could be caused by factors not considered in the experimental design and by test parameters that are specified with insufficient precision in the guidelines. This work focused on some different points of the guidelines. One of the parameter we took into account is the temperature: the EPPO guidelines accept to run laboratory toxicity tests on adult honeybees at the temperature of 25±2°C. In our studies we noticed that the LD50 value may vary significantly within this temperature range. Furthermore, the nature of the relationship LD50 -temperature seems to be dependent on the chemical group of the pesticide tested. Thus, the current guidelines could allow the subject interested in the pesticide registration to run toxicity tests at the temperature level that produces less effects. In addition, EPPO guidelines describe the age of the bees that should be used in the tests and how they should be collected and fed. Our experiments highlight the importance of these parameters for a valuable risk assessment and demonstrates that the

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official methods are not always the best ones. Proposals for improvement of official risk assessment guidelines are provided.

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Giorgia Lombardo

Università degli Studi di Parma

CO N T I N U O U S O C C U R R E N C E O F I N T R A-I N D I V I D U A L CHROMOSOME REARRANGEMENTS IN THE PEACH POTATO APHID MYZUS PERSICAE (HEMIPTERA:APHIDIDAE)

Analysis of the holocentric mitotic chromosomes of the peach-potato aphid Myzus persicae (Sulzer) from clones 50, 51 and 70 revealed different chromosome numbers, ranging from 12 to 14 even within each embryo, in contrast to the standard karyotype of this species (2n=12). Chromosome length measurements, combined with fluorescent in situ hybridization experiments, revealed that the observed chromosomal mosaicisms are due to recurrent fragmentations of chromosomes X, 1 and 3. Contrarily to what reported up till now in literature, X chromosomes were frequently involved in recurrent fragmentations, in particular at their telomeric end o p p o s i t e t o t h e n u c l e o l a r o r g a n i z e r r e g i o n . Supernumerary B chromosomes have been also observed in strains 50 and 51. The three analyzed aphid clones showed recurrent fissions of the same chromosomes in the same regions suggesting that M.

persicae genome has fragile sites that are at the basis of

the observed changes in the chromosome number. Experiments of male induction showed that M. persicae clones 50, 51 and 70 are obligately parthenogenetic suggesting that the reproduction by apomictic parthenogenesis favoured the stabilization and the inheritance of the observed chromosomal fragments.

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Giovanni Lazzari

Università degli Studi di Parma

ECOETHOLOGY OF THE MULTITROPHIC RELATIONS AMONG ANTS, SAP-SUCKING INSECTS AND PREDATORY BEETLES: A CASE STUDY IN WHICH TROPHOBIOSIS DOES NOT OPERATE

This research aimed to analyze some aspects of multitrophic relations among Argentine ant (Linepithema

humile, Hymenoptera: Formicidae), cotton scale insects

(Planococcus citri, Hemiptera: Pseudococcidae) and ladybirds (Cryptolaemus montrouzieri, Coleoptera: Coccinellidae). On the basis of our previous researches conducted in a semi-natural environment, these relationships did not seem to follow the classic paradigm of the trophobiosis: although the ants received honeydew from the scale insects, they did not protect the mealy bugs from predation. In order to understand this situation, accurate lab investigations were conducted and the following questions were addressed:

1) Can ant food ecology and the importance of scale insects as food resource influence the modality of reaction of the ants towards ladybirds?

2) Is the missing aggressive ant reaction against the predator due to a particularly effective defensive system of this ladybird species (both in the larvae or in the

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specific artificial proteic diet and only the proteic diet. Each colony was treated with 18 different experimental treatments (for a total of 324 experiments) using living animals or surrogates such as: an adult or a larva of

Cryptolaemus montrouzieri (alive or dead), a larva of Cryptolaemus montrouzieri with or without its wax

filaments, a potential dead prey with or without filaments extracted from Cryptolaemus montrouzieri larvas. In every experiment, through a scanning sampling method, the behaviour of every ant that came near the treatment was recorded, for a total of 15864 behavioural recordings. It was possible to calculate an appropriate “aggression index” which describes the behaviour adopted from every colony towards the treatments. The experiments demonstrated that the diet does not influence the aggressive behaviour of ants towards the predator. It means that ants which are strictly dependent from sugar secretions offered by scale insects are not particularly motivated in the defense against the beetle. We shifted our attention on the reaction of the ants towards the ladybirds, both in the adult and in the larval stage. The results showed that ladybirds can rely upon many adaptations that allow them to avoid or limit the attacks of the ants. Although adults are more attacked than larvae, they can take advantage of behavioural adaptations (fast movements, mechanical protections, flight, emission of toxic substances) which allow them to limit the negative effects. On the other hand, larvae are almost ignored by ants. The main cause of this invulnerability is the presence of a close layer of wax filaments that cover them and that can have both a physical and a chemical deterrent effect. In addition, some tests highlighted also the defensive effectiveness of

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larvae secretions which are rich in several alkaloids of different origin. Finally, we are considering other hypothesis concerning the possibility of ladybird larvae chemical disguise: they can acquire odours similar to those of their preys or the wax filaments may contain substances able to influence the ant behaviour.

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Ginevra Cusseau, David Baracchi, Duccio Pradella, Stefano Turillazzi

Università degli Studi di Firenze

DEFENCE REACTIONS OF APIS MELLIFERA LIGUSTICA

AGAINST ATTACKS FROM THE EUROPEAN HORNET VESPA CRABRO

The predatory behaviour of Vespa crabro hornets on the honeybee Apis mellifera ligustica and the counter strategy of the prey were observed and described in two apiaries of 27 and 41 colonies in Central Italy. Observations were carried out in the second half of October and accompanied by experiments aimed at determining the mechanisms of honeybee defence. We confirmed that V. crabro represents a relatively mild predator for A. mellifera ligustica but it can have a considerable impact on already debilitated colonies. Hornet predatory strategy is to spot then swoop on returning foragers. Honeybee defence centres on forming packed aggregations of individuals near the hive opening, which probably deters the wasps from entering. Coordinated behaviour by the bees, which cling together in groups, can knock the approaching hornets down, which are then totally covered by the bees. This balling behaviour has the effect of over-heating the predator whose lethal thermal limit is about 44 °C, although other factors, such as carbon dioxide emission and the release of venom by the honeybees, may also contribute to the death of the hornet. Comparing the differences and similarities of this behaviour with those observed in other species of Apis and Vespa reveals that these two species

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are an interesting model for the study of the evolutionary arms race.

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Martina Mueller, Vito Scicchitano, Andrea Luchetti

Università degli Studi di Bologna

FACULTATIVE PARTHENOGENESIS IN TERMITES: AN ANALYSIS WITH MOLECULAR MARKERS IN RETICULITERMES LUCIFUGUS

AND R. URBIS (ISOPTERA,RHINOTERMITIDAE)

Termites (Isoptera) are an order of social insects. They build colonies formed by three different castes: workers, soldiers and reproductives (royals). Workers and soldiers are sterile and their role is to manage and to protect the colony, respectively. A new colony is generally funded by a royals couple; during the swarming season, they join together and mate. Afterwards, the couple is frequently replaced by secondary neotenic reproducers. In two species of the genus Reticulitermes (Rhinotermitidae), R.

speratus and R. virginicus, the secondary queens are

produced by the primary queen through parthenogenesis. Eggs that have not been fertilized become diploid by terminal fusion, thus having a completely homozygote genotype. This results in an advantage for the colony because the secondary queens are not related to the primary king, so that they can mate without the risk of inbreeding. In the study we present here we have sampled seven colonies of Reticulitermes urbis and three colonies of R. lucifugus from different sites in Italy. We have collected both workers and secondary reproducers. In the colonies of R. urbis we found both secondary queens and kings, with a sex ratio 1:1, whereas in those of R. lucifugus we found only secondary queens. This makes R. lucifugus suspect to produce secondary queens by parthenogenesis. After having extracted the DNA from the individual termites, PCR amplifications at

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six microsatellite loci and one mitochondrial DNA gene (cox2) were carried out. They are used to estimate the genetic variability, for identifing the colony structure in the two species and to confirm the reproductive strategy for producing secondary queens and kings. If the R.

lucifugus primary queen uses parthenogenesis for

producing secondary queens, these would result all homozygotes unlike the workers. For R. urbis on the other hand we do not expect to find any difference regarding homozygosity of workers and secondary reproductives. First data from one colony of R. urbis and three colonies of R. lucifugus follow these expectations. Furthermore, data from the mitochondrial DNA marker clearly reveal different origins for the R. urbis sampled colonies, with a possible mixed colony R. urbis/R.

lucifugus. We will conduct further analysis for better

examine the colony structure in both species and for having a more complete insight into their reproductive strategies.

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Maria Cipollini

Università degli Studi di Firenze

A QUANTITATIVE THRESHOLD FOR NEST-MATE RECOGNITION IN HONEYBEE APIS MELLIFERA

Nest-mate recognition is fundamental in social insect’s colonies; in this way they protect themselves from intrusions of parasites or non nest-mate plunderers. The aggressiveness of colony’s individuals against intruders is mediated by their cuticular semiochemicals. In ants and wasps recent studies identified the smallest amount of cuticular compounds required to elicit a reaction and due to the lack of comparable data available for Apis

mellifera we investigated the subject in such species. In

June 2011 we carried out a behavioural experiment on 20 beehives. Every colony was stimulated by presentation, for 1 minute, of 5 different fractions of the cuticular extract of foragers: total extract, 1/8, 1/4, 1/2 and, as a control, the solvent use for extraction. We found that different amounts of cuticular hydrocarbons (CHC) evoked q u a n t i t a t i v e l y d i ff e r e n t b e h a v i o u r a l r e a c t i o n s (antennaments, bites, pursuits) in the tested honeybees. The relation between CHC quantity and the elicited response of colonies supports the idea that a quantitative threshold for the recognition of intruders exists in

A.mellifera and this threshold would be attested around

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Rachele Nieri

Università degli Studi di Firenze

ADULT-IMMATURE BROOD INTERACTIONS: A COMMUNICATION CHANNEL TO BE EXPLOITED BY THE SOCIAL PARASITE P.

SULCIFER

The relationship mother-offspring is fundamental for many species; particularly in social insects, where it is one of the crucial point for the evolution of sociality. However, even in a well-known model system as the paper wasp Polistes dominulus, it remains unknown if an immature brood-adult communication exists and in case which is the communication system exploited by this close and important relationship. In the model system of this study, the obligate social parasite P. sulcifer and its host P. dominulus, parental care, exclusively provided by host workers, highlights the importance for the parasite to assure all resources for an optimal development of its brood. Previous studies (Cervo et al., 2004) have shown that the immature brood of the parasite species grows more rapidly than the host’s one. Moreover both larvae and pupae of P. dominulus take longer to develop if they are reared in a parasitized colony. Observations on host behavior in parasitized colonies showed that parasite larvae were visited more often than the host larvae,

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foraging rate of parasitized and unparasitized colonies reared in semi-natural conditions. A higher nutrition rate towards the parasite brood can be determined either by an active behavior of the brood itself or by the adult parasite, which may affect the workers behavior directing more parental cares toward its brood. In future I will investigate further communication channels used by the parasite to better exploit the host colony.

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Ilaria Protti

Università degli Studi di Firenze

MODIFICATION OF THE CUTICOLAR CHEMICAL PROFILE OF

APIS MELLIFERA INDUCED BY THE MITE VARROA DESTRUCTOR Apis mellifera and the mite Varroa destructor bind a

host-parasite relationship on a chemical basis. The aim of the study is to find out if the presence of mites on body surface of A.mellifera can provide changes in the CHCs profile and to verify if those modifications may enhance the acceptance of honeybees affected by Varroa into new colonies. Laboratory work consisted in the set up of 3 different honeybees categories related to different age/ task which were put togheter with Varroa mites for different time-gaps. All the chemical analysis of CHCs were performed by Gas Cromatography coupled with Mass Spectrometry, which revealed the composition of CHCs profile of healthy and affected by Varroa honeybees. Statistical analysis of compounds showed us that several methyl-Hydrocarbons undergoes to a significant increase after that honeybees have been kept in touch experimentally with Varroa mites. Adult honeybees foragers kept together with Varroa mites for 7 days, have recorded the most significant increase in methyl-Hydrocarbons. Youngster honeybees undergoes

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defence/aggression behaviour is stronger when a dummy of non-healthy forager (with richer methyl-hydrocarbons profile) was introduced to the colony. This finding may suggest that A. mellifera is able to defend its colony from the entrance of Varroa-infected honeybees.

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Silvia Bedetti

Università degli Studi di Parma

THE ANT FAUNA IN GRAN PARADISO NATIONAL PARK: ANALYSIS OF BIODIVERSITY AND OF COMMUNITY STRUCTURE

The research project focused on ants in the Gran Paradiso National Park originates from the data collected during my bachelor's thesis sampling activities in Rovenaud (AO, Italy) during summer 2009. The importance of ants, as observed in the analysed alpine ecosystem, gave rise to a closer examination of the Formicidae present in the Park. For this reason, the new research project for my master thesis consists of sampling activities that take place during summer of 2011 and 2012 in each one of the five valleys that compose the Park, focusing in particular on the two valleys belonging to Piemonte region. The main aim of the project is to characterise the ant fauna in the alpine habitat of the Park. For this purpose, three are the main objectives to be reached: to obtain a check-list of the present ant species; to investigate the daily and seasonal activity rates, considering both general trends and single species patterns; to analyse the community's structure and the dominance hierarchies occurring between different species. The check-list will provide for a basic complete

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Patrizia Cherubini

Università degli Studi di Parma

THE ANT FAUNA IN GRAN PARADISO NATIONAL PARK: ANALYSIS OF ACTIVITY RATES

During summer 2011, I started my internship for the Bachelor thesis in Valle Soana (Torino), an alpine valley inside Gran Paradiso National Park. The sampling activities regarded four transects at different elevation and were divided into three sessions, each lasting fifteen days, from June to August. My project, that is part of a bigger one about the analysis of ant biodiversity and ant community structure, focuses on the study of daily and seasonal activity rates of the ant fauna in the Park. I used a standardized protocol based on the “Global Ant Collaboration” project in which my laboratory is involved and that is lead by Pr. Nathan Sanders and Pr. Rob Dunn. For this purpose, two sampling methods were used: baits and pitfall traps. Both these traps are placed in four different times during each sampling day. The collected data, that I'm processing, will give information about daily activity rates of ants, their feeding preferences and resources monopolization ability for each species.

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Bedetti Silvia

Dipartimento di Biologia Evolutiva e Funzionale Università degli Studi di Parma

Viale Usberti 11/a, 43100 Parma e-mail: silvia_bedetti@libero.it

Web Site: www.myrmecologylab.wordpress.com

Cappa Federico

Dipartimento di Biologia Evoluzionistica “Leo Pardi” Università degli Studi di Firenze

Via Romana 17, 50125 Firenze e-mail: federico.cappa@unifi.it

Cherubini Patrizia

Dipartimento di Biologia Evolutiva e Funzionale Università degli Studi di Parma

Viale Usberti 11/a, 43100 Parma

e-mail: patrizia.cherubini@studenti.unipr.it Web Site: www.myrmecologylab.wordpress.com

Cipollini Maria

Dipartimento di Biologia Evoluzionistica “Leo Pardi” Università degli Studi di Firenze

via Romana 17, 50125 Firenze e-mail: mariacipollini@virgilio.it

Ginevra Cusseau

Dipartimento di Biologia Evoluzionistica “Leo Pardi” Università degli Studi di Firenze

via Romana 17, 50125 Firenze e-mail: mariacipollini@virgilio.it

Dunn Rob

Department of Biology

North Carolina State University - USA e-mail: rrdunn@ncsu.edu

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Giovanetti Manuela

Dept. AR.BO.PA.VE.

Università di Napoli “Federico II” Via Università 100, 80055 Portci (Na) e-mail: manuela.giovanetti@ gmail.com

Lazzari Giovanni

Dipartimento di Biologia Evolutiva e Funzionale Università degli Studi di Parma

Viale Usberti 11/a, 43100 Parma

e-mail: giovanni.lazzari@studenti.unipr.it

Web Site: www.myrmecologylab.wordpress.com

Lombardo Giorgia

Dipartimento di Biologia Evolutiva e Funzionale Università degli Studi di Parma

Viale Usberti 11/a, 43100 Parma e-mail: lombardo.giorgia@libero.it

Web Site: www.myrmecologylab.wordpress.com

Meconcelli Stefania

Università di Torino

via accademia albertina 13, 10123 Torino

e-mail: stefymeco@gmail.com

Mueller Martina

Dipartimento di Biologia Evoluzionistica Sperimentale Università degli Studi di Bologna

via Selmi 3, 41026 Bologna

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Petrocelli Iacopo

Dipartimento di Biologia Evoluzionistica “Leo Pardi” Università degli Studi di Firenze

Via Romana 17, 50125 Firenze e-mail: iacopo.petrocelli@alice.it

Piras Mereu Pierpaola

Dipartimento di Scienze Agrarie e degli Alimenti, Università degli Studi di Modena - Reggio Emilia Via Amendola 2 - Pad. Besta, 42100 Reggio Emilia e-mail: tupau@tiscali.it

Protti Ilaria

Dipartimento di Biologia Evoluzionistica “Leo Pardi” Università degli Studi di Firenze

Via Romana 17, 50125 Firenze e-mail: ilaria@istantarte.it

Spotti Fiorenza

Dipartimento di Biologia Evolutiva e Funzionale Università degli Studi di Parma

Viale Usberti 11/a, 43100 Parma e-mail: fiorenzaspotti@alice.it

Web Site: www.myrmecologylab.wordpress.com Tosi Simone

Dipartimento di Scienze e Tecnologie Agroambientali (DiSTA)

Università degli Studi di Bologna via Fanin 44, 40127 Bologna e-mail:s.tosi@unibo.it

References

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