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The Fruitfly Project

INTRODUCTION

Importance of study group

Fruit flies (Diptera: Tephritidae) are one of the most economically important groups of insects in the Afrotropical Region. They cause millions of Euros of damage to fruits and vegetables, and are a major constraint to commercial and subsistence farming in the region. The family Tephritidae includes more than 5000 species worldwide, approximately 1400 species of which develop in fleshy fruits (Norrbom et al 1999). Nearly 250 of these species are capable of achieving pest status by feeding on plants of economic importance (White and Elson-Harris 1992). The Mediterranean fruit fly, or Medfly, Ceratitis capitata (Wiedemann), is currently the most important of these pests from an invasive species perspective. Of African origin, it has spread to several other continents where it causes millions of Euros in damage. It also threatens other horticultural areas (such as California and Florida in the USA and regions in eastern Australia) resulting in very expensive detecting and monitoring programmes in these regions. Several Asian representatives of the genus Bactrocera have been reported as invasive species over de last decades in other parts of the world, causing heavy losses in the fruit industry.

The destructive association of several species with commercially grown fruit and vegetable crops makes them the subject of intensive agricultural research. But fruit flies are also biologically diverse and form a significant part of the biota of any region. Besides the several pest species, the large majority of the true fruit flies are limited to a small number of indigenous host fruits, mainly from trees and shrubs. Most of them are associated with forested areas, and can be used as indicator species for the biodiversity of a given area. In addition, several fruit fly larvae develop in other parts of host plants such as the stems or flowerheads.

Fruit flies in Africa

Tropical and subtropical regions are growing markets for fruit production and export. The Sub-Saharan African fruit industry is still relatively small (except for South Africa) but has been growing considerably in the last years. Also, the fruit production supplies an essential addition to local nutrition, and provides income for people in these countries. For several tropical fruits, the production is mainly by small-holder producers (80% in the case of mango growers in Africa (Lux 1999)) and a large part of the production is for local consumption in the rapidly expanding urban markets. Fruit infestation on average can reach 20-40% and is considered the main constraint for production and export of quality (sub)tropical fruits throughout the continent (Lux 1999). The problem is aggrevated in recent years by introduction of exotic pests such as Bactrocera dorsalis (formerly known as Bactrocera invadens Drew et al., 2005). In many countries, the importation of most commercial fruits is severely restricted by quarantine laws to prevent the spread of fruit fly species. The costs of constructing and maintaining fruit treatment and eradication facilities is also considerable.

Recent research on fruit flies in Africa

Over the last years, several international programmes have addressed the issue of fruit fly pests in Africa. The International Centre for Insect Physiology and Ecology ( ICIPE), Nairobi, Kenya, started the African Fruit Fly Initiative ( AFFI) with the aim of alleviating fruit fly pest problems for African smallholder families, and to increase the yield and quality of their crops. USAID and USDA funded projects (through Texas A&M University) focused on enhancing expertise in the systematics of African tephritid fruit flies and their parasitoids. The main focus of these projects was to provide a capacity for the correct identification of certain groups of African tephritids, and to collate all relevant data from specimens and literature to facilitate species identification. Other collaborative activities (a.o. by the Royal Museum for Central Africa) have been undertaken in conjunction with these programmes, focusing on retrieving information from the main entomological collections in Africa and in the Western World. In recent years several research programs have focused on studying the population dynamics and ecology of, and interspecific interactions between pest species. These activities are conducted both in western (a.o. by CIRAD/IITA in Benin) and eastern (a.o. by the Sokoine University of Agriculture, Morogoro in Tanzania and E. Mondlane University, Maputo in Mozambique) Africa. ICIPE is continuing the AFFI under the current African Fruit Fly Programme, comprising basic and applied research aspects with strengthening capacity for famers¿ communities in several African countries. USDA has been supporting several surveying programs in southern Africa through their USDA-APHIS office in Pretoria, South Africa, while the joint FAO/IAEA Division of Nuclear Applications in Food and Agriculture runs several regional and national projects on fruit flies in Africa. Both proponents of this study were actively involved in all of the above mentioned projects at different levels.

These activities have resulted in a large amount of data on Afrotropical fruit flies that have undergone rigorous quality assessment and quality control procedures. The data are therefore very reliable. The database also includes more historical records (like the USDA sponsored expeditions to Africa in early and mid 20th Century, in search of natural enemies of pest species (Silvestri 1913; Bianchi & Krauss 1936; Clausen et al 1965)).

ENBI programme

ENBI (European Network for Biodiversity Information) was an initiative funded by the European Union, and had the general objective to manage an open network of relevant biodiversity information centres in Europe. This programme aimed at being the European contribution to the Global Biodiversity Information Facility (GBIF), promoting two main fields of biodiversity study activities:

One element of ENBI (WP13, work package 13) dealt with making non-European biodiversity data in European repositories globally available. Notably, because many European countries have a colonial past, a large share of global biodiversity information, especially from developing countries in the tropics resides in databases of European institutions (including museum and botanic garden collections). With a still very fragile infrastructure for taxonomy in tropical developing countries and a very limited number of well-trained taxonomists, there is a great need for high quality collections-based information among local (para)-taxonomists, conservationists and other users of floristic and faunistic information. Data sharing may take the form of making available (visible, downloadable, analysable) on the Internet, current names, digitised images and collecting data of selected specimens, for which there is an urgent information need in the developing countries. Within WP13 a number of feasibility studies were planned. One such feasibility study was the development of a queryable website for Afrotropical Ceratitidini (Diptera, Tephritidae). Some of the main fruit fly pest species belong to this taxonomic group, especially within the genera Ceratitis, Trirhithrum and Capparimyia. The most notorious one, the Mediterranean fruit fly (Ceratitis capitata) has been highlighted above. Other related pest species in Africa are the Natal fruit fly (C. rosa), the mango fruit fly (C. cosyra), the coffee berry fruit fly (Trirhithrum coffeae) and the caper fruit fly (Capparimyia savastani).

The initial website accessible through this URL was the result of that feasibility study. In 2007, the website could be expanded thanks to a Biodiversity Digitization Project funded by the Belgian Biodiversity Platform. This allowed expansion of the initial dataset to include all African representatives of the pest genera Dacus and Bactrocera. These genera include notorious African pests of Cucurbitaceae, such as D. bivittatus and D. ertebrates, as well as exotic species that were introduced in Africa such as Zeugodacus cucurbitae and B. dorsalis. Data for these genera became available in 2006 when the NHM partner completed a monograph on the representatives from Africa and the Middle East (White, 2006). Furthermore, the genus Carpophthoromyia was revised by De Meyer (2006). In 2010 a further series of specimens were added. White & Goodger (2009) described an additional number of species of the genus Dacus. De Meyer (2009) revised the genus Perilampsis a group of ceratitidine species attacking the African mistletoe family Loranthaceae. De Meyer & Freidberg (2012) revised the genus Neoceratitis, which is known to attack Solanaceae and comprises the pest species N. cyanescens. The biodiversity of the western African fauna was analysed (De Meyer et al., 2013) with description of a new Dacus species. More recently, an integrative approach to resolution of cryptic species complexes in fruit flies was initiated by the joint FAO/IAEA Division. This resulted in a series of publications (De Meyer et al., 2015). Several new Ceratitis species were described because of this and related studies (De Meyer et al., 2016). With these additions, the website now includes all major genera of the dacine fruit flies.

BEBIF and Belgian Biodiversity Platform involvement

Playing its role as Belgian GBIF node, BeBIF has provided the public data concerning this project to the GBIF network. As subcontractor for this ENBI WP13 project, BeBIF has designed and implemented this User Interface with all its functionalities, including the log in service. Some technical data validation has been performed on the database itself (checking dates, data types, …). BeBIF has participated financially to this feasibility study by providing some seed money for semantic data quality control, performed by relevant experts, designated by the providers. BeBIF, recently merged with other Belgian Biodiversity related units to form the Belgian Biodiversity Platform. The latter provided the technical assistance for the expansion of the initial website, as well as financial support for data logging, quality control and imaging with relation to the extended website.

Objectives

The main objective of this pilot study is to make all relevant information of the major dacine fruit fly genera of Africa accessible to a wider public. This can be obtained through the completion and transformation of a currently available MS Access database on Afrotropical dacines into a searchable website based platform that will:

Limitations of scope: the pilot study is focusing on a group of Afrotropical fruit flies only. Reason is that, over the last decade years several projects have focused on this group (cf. above) and that a mass of specimen related data are available. Afrotropical is used here in the biogeographical sense, hence the region below of the Sahara dessert. However, some additional records from northern Africa and the Middle East are included but not as exhaustive as those for the true Afrotropical region.

Identification key

White (2006) provided the first comprehensive identification key for African Dacus and Bactrocera species in more than 20 years. The previous monograph for this group (Munro, 1984) was generally considered as being difficult to use for species identification. With the additional species described in White & Goodger (2009), the earlier published key by the first author has been altered considerably. We, therefore, provide a downloadable pdf document of the updated key through this website.

The Royal Museum for Central Africa developed a series of electronic multi-entry keys for all the genera included in this database (Virgilio et al., 2014). This series is now available at: http://fruitflykeys.africamuseum.be/.

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WEBSITE STRUCTURE

The information is based on data currently incorporated in a relational database in MS Access©. This database consists of a specimen table linked to associated tables on taxonomic, host plant and locality information. The information is provided in the website at two levels: taxon information and specimen information

Taxon information

This entails all relevant data with regard to the taxon, in this case the species concerned. The following items are provided:

Specimen information

This includes all relevant data that are linked to individual specimens or block records (i.e. set of specimens with identical data). This information is the standard information that is usually associated with collection specimens: the place where and date when the specimen was collected, name of collector and collection where the specimen is deposited, the status of the specimen (type or non-type), etc. For fruit fly specimens, there are two additional elements of information that are often available.

Lure name: Males of several Ceratitits and Dacus species can be attracted with special chemicals, sometimes called parapheromones. These substances are not naturally used in intraspecific communication, as true pheromones, but they induce similar responses. A review is given by Cunningham (1989). Often traps, baited with these lures, are used for collecting fruit flies. Responses are specific at a generic or even subgeneric level, and this information can be of importance for detection or monitoring programmes.

Host plant name: Because of the phytophagous life history of the fruit fly larvae, there is a distinct insect/host relationship in Tephritidae. Several species are polyphagous attacking a wide variety of unrelated plant genera and families. Others are restricted to particular host families or genera. The data information is variable in that the host record can be based on true rearing of the fly from that particular plant, or merely an association (like adult fly sitting on the plant) or that the information on the label is insufficient to conclude whether the material was actually reared or not. These different categories are taken in consideration. Most of the African host plant information for the genus Ceratitis is also available in printed version (De Meyer 2002).

Categories of ID: Most of the material was identified by either of the proponents or by colleagues who could provide a reliable identification. Some records, however, could not be verified because the material upon which the record is based, was not available for study. These unconfirmed records are considered either reliable or questionable, depending on the source.

All records are ranked in a particular category, based on the differences in both of the last items (exact association between host plant and fly, and reliability of identification). Three main categories are recognised with in total seven different subcategories (indicated by a capital letter A,B,C,D, E, F or G):

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DATA SOURCES

Information in this website originates from three main sources: taxonomic revisions that were produced over the last 20 years by the two proponents (often in collaboration with other specialists), secondly specimens that are housed in natural history museums and institutions and that were routinely verified during study visits at these institutions or by material sent on loan for study, and thirdly recent projects that were targeted at compiling information on fruit flies in Africa.

Taxonomic revisions

White (1989) stated that there was an urgent need for taxonomic studies to provide accurate identifications of fruit flies. Especially with regard to the Afrotropical continent and specifically to Dacine genera. In the 1990ies taxonomic studies of main genera of this group were started, which resulted in a number of revision papers that were recently published:

These papers form the basis for the taxonomic information incorporated in this website: the descriptions are based on those provided in the papers and the relevant diagnostic drawings are reproduced. Also, large proportions of the material studied, are listed in these publications (under sections such as 'material examined').

Collection holdings

The majority of the fruit fly data included in this database, are based on specimens that are incorporated in collections worldwide. In total, more than 75000 specimens, housed in close to 50 different collections, were studied. Material was kindly put at the disposal of the researchers by the following institutions:

For each specimen (or block record) in the specimen information, the depository of that actual specimen is indicated with the institutional acronym as listed above. In case the record is not based on specimens studied from a particular collection, this is indicated with 'ANON '.

Recent projects

As mentioned earlier, over the last decade, several international programmes have addressed the issue of fruit fly pests in Africa. Several of these programmes have produced large quantities of relevant data that are incorporated in the current database. The most important were the following two USAID and USDA funded projects co-ordinated by R. Wharton of Texas A&M University:

Smaller collaborative activities have been undertaken in conjunction with these programmes. The AFFI project of ICIPE, for example, had a collecting programme in different African countries in collaboration with the Royal Museum of Central Africa, Tervuren Belgium (RMCA). Also the results of the Programme Régional de Recherche Aplliquée sur les Mouches des Fruits, administered by the Indian Ocean Commission and for which the host plant data were published by Quilici & Jeuffrault (2001) are included. The RMCA has conducted a collaborative research, funded by Belgian Development Cooperation, with the Sokoine University of Agriculture (Morogoro, Tanzania) to study the diversity, seasonality and population dynamics of fruit fly pests in Central Tanzania. CIRAD, in collaboration with IITA, is studying fruit flies in western African countries over the last decade, providing several faunistic records, mainly by the work of J.-F. Vayssières and G. Goergen. In addition, several surveying programs, such as those conducted by USDA-APHIS in southern Africa, are ongoing and provide regaular additions of specimens records.

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INTELLECTUAL PROPERTY RIGHTS

Collection specimens are the property of the respective institutions where they are deposited. All data associated with those particular specimens are therefore also property of those institutions. Most of them are already available and belong to the public domain since there were published in taxonomic revisions under headings such as 'Material examined '. When information of a particular specimen is used, reference should be made to the museum where it is housed, by indicating the institution 's name or acronym. Copyright of the images (photographs or drawings) used is indicated on the individual image. This is either the institution where the photograph was taken or the photographer that took it. In case of published drawings, the copyright remains with the publisher. Permission was sought from the publishers for reproducing the drawings published in Bulletin of Entomological Research, Zoological Journal of the Linnean Society, Systematic Entomology, Cimbebasia, Journal of Natural History, Zootaxa and Zoologica Scripta.

Whenever information that is provided through this website, is used by third parties, reference should be made to the website for example by the following or similar phrasing:

De Meyer, M. & I.M. White. 2004. True fruit flies (Diptera, Tephritidae) of the Africa. A queryable website on taxon and specimen information for afrotropical Dacine fruit flies. http://projects.bebif.be/enbi/fruitfly/ - Tervuren: Royal Museum for Central Africa. Access date: 04/12/2024.
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CD-ROM VERSION

Access to the internet is still not straightforward in several countries, especially in the developing world. Since the data herewith presented deal with information mainly from the African continent, we want to make the data as easily accessible as possible. Therefore a CD-ROM version of website is available upon request. For further information, please contact Marc De Meyer at marc.de.meyer africamuseum.be

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DISCLAIMER

Although care was taken that the data incorporated in the database are correct, the proponents take no responsibility whatsoever with regard to the use of the data provided here by third parties. Persons retrieving information from this website for their own research or for applied aspects such as pest control programmes, do so at their own risk.

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FEEDBACK PLEASE

Before and during the development of this database, we discussed the design and information to be added with several colleagues in the field, as well as with non-specialists who are nevertheless interested in the kind of data hereby provided. Also the BeBIF partners, with their larger experience of website development for biodiversity related information, assisted greatly in the development.

Databases like these, however, can only be improved upon if we get feedback from the end-users. That way layout, possibilities, and information provided can be altered to the demand of the users and the website becomes more demand driven. Attached is a short comment reporting form that will allow you to give us a response. Please, share your comments and suggestions with us.

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ACKNOWLEDGEMENTS

Our sincere thanks go to the numerous institutions and their respective curators for allowing us to include data, based on specimens in their holdings, into this database.

Many thanks to Patricia Mergen, Johan Duflost, Frédéric Wautelet and Julien Cigar of BeBIF for their assistance and support in the development of the initial website, and to André Heughebaert, Nabil Youdjou and Julien Cigar of the Belgian Biodiversity Platform for their assistance and support in the development of the extended website. BeBIF and the Belgian Biodiversity Platform themselves acknowledge support from the Belgian Science Policy for their general program.

A large part of data providing and gathering was done through various projects over the last years, in particular USAID grant No. PCE-G-00-98-00048-00; USDA/NRI grant No. 9703184; USDA/CSREES grant No. 00-52103-9651 (all to R. Wharton, Texas A&M University); IFAD T.A. Grant No 426 to AFFI/ICIPE; grants for the F13 project within the Framework program between the RMCA and the Belgian Development Cooperation, travel grants of the Sabrosky-Williston Fund (USNM) and FWO Vlaanderen for study visits by M. De Meyer to BMSA, IITA, PPRI, NMSA, SUS, and USNM. The finalisation of data input and actual development of the website was only possible through financial support provided by Work Package 13 of the European Network for Biodiversity Information (EU funded network contract EVK2-CT-2002-20020). Many thanks to Henrik Enghoff and Isabel Calabuig (co-ordinators of WP 13) for supporting us in this respect.

Many thanks to our respective institutions, the Royal Museum for Central Africa Tervuren and the Natural History Museum London, for providing us with general working facilities. Finally, many thanks to all the colleagues and persons who assisted us in several ways throughout the years while compiling the information that is now synthesized in this database, especially to Hilde Engelbeen, Geoffrey Hallaert, Stéphane Hanot, Myriam VandenBosch, Saskia Vanderhaegen, and Nadine Van Noppen for their help in actual datalogging and image preparation.

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LITERATURE CITED

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HOW TO USE?

As indicated the information can be accessed through two different channels: either taxonomic information or specimen information.

For taxonomic information, go to the taxon list and select a name. You will then have the option to look at different information sets available for that particular taxon (description, images, distribution map). If the name you selected is considered a junior synonym, look under the senior synonym's name.

For specimen information, you have three different kinds of query levels that are explained below

Queries

The full specimen information covers 24 different fields with regard to taxonomic status, georeferences, collection codes, etc. Not all of this information is always relevant to persons querying the database. Often, more limited queries need to be answered such as what fly occurs where or what species has been found in association with mango or coffee. In order to facilitate these varied types of questions, the database can be queried through three different search levels, depending on the kind of information one is looking for.

Basic search: this will give the taxonomic name of specimen, the country of origin, the plant host (Latin name, vernacular English name if available and plant family) and a ranking on ID reliability with the groupings mentioned earlier. Duplicate records are omitted.

Advanced search: provides the same fields as basic search plus some additional ones like the name of exact locality, date of collection, status of the specimen, name of museum depository, and lure (if applicable). Again duplicate records are omitted.

Specimen information level: gives all fields available, hence the same fields as an advanced search plus: latitude & longitude of locality, exact number of specimens, name of collector, and type of association with host plant data.

Each of these search forms can be queried through a filter system. By selecting names from the scroll down menu for the individual cells, the user can filter out the required information. For example, in the basic search form, by selecting 'Kenya' in the 'country' field, all records of fruit flies from Kenya will be shown. By selecting 'Kenya' as well as' mango' in the 'English host plant name' the records will be narrowed down to those from Kenya with mango as host. General queries like 'which species are found in Kenya ' or 'which species are reported from mango in Kenya' can thus be answered in this way. If one wants the standard information on specimens, the advanced search can be used. Specimen information level gives all data related to a particular specimen or block record.

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