Revista IDE@ - SEA, nº 6B (30-06-2015): 1–20. ISSN 2386-7183 1 Ibero Diversidad Entomológica @ccesible www.sea-entomologia.org/IDE@ I ntroduction The biodiversity of terrestrial arthropods in Madeira and Selvagens Manual Versión española The biodiversity of terrestrial arthropods in Madeira and Selvagens archipelagos Mário Boieiro1,2, António Franquinho Aguiar3, Carla Rego1,2, Paulo A.V. Borges1,2 & Artur R.M. Serrano4 1 cE3c – Centre for Ecology, Evolution and Environmental Changes / Azorean Biodiversity Group and Universidade dos Açores - Departamento de Ciências Agrárias, 9700-042 Angra do Heroísmo, Açores, Portugal. 2 CITA-A and Portuguese Platform for Enhancing Ecological Research & Sustainability (PEERS). 3 Núcleo de Entomologia, Laboratório Agrícola da Madeira, 9135-372 Camacha, Madeira, Portugal. 4 cE3c – Centre for Ecology, Evolution and Environmental Changes / Faculdade de Ciências, Universidade de Lisboa, 1749-016 Lisboa, Portugal. 1. The archipelagos of Madeira and Selvagens The oceanic archipelagos of Madeira and Selvagens are located in the eastern Atlantic, between 30-33ºN and 15-17ºW, being part of the Macaronesia biogeographical region. The archipelago of Madeira is composed of Madeira Island, Porto Santo Island and its surrounding islets, and the Desertas islands, which include Deserta Grande, Bugio and Ilhéu Chão (Fig. 1). This archi- pelago is distanced from the Iberian Peninsula by 1000 km, but its distance to the nearest mainland (coast of Morocco) is just 600 km. All the islands of Madeira archipelago are volcanic in origin and have originat- ed from a single volcanic building – the Madeira-Porto Santo complex. The rugged orography and the altitudinal span of Madeira Island led to the occurrence of some natu- ral habitat-types which are distributed along the altitudinal gradient (see Plate I). In the basal floor, coastal vegetation and scrublands are dominated by sclerophyllous, xerophytic and thermophilous shrub species, like Euphorbia piscatoria, Maytenus umbellata and Sideroxylon mirmulans. At intermediate altitudes, the relict native forest – the Laurisilva – covers a considerable area. This forest is dominated by tree species of the Lauraceae family, like Apollonias barbujana, Laurus canariensis, Ocotea foetens and Persea indica, together with other tree species like Clethra arborea, Ilex perado and Morella faya. Madeira has the largest area of Laurisilva (~15,000 ha), encompassing a fifth of the island area, and presents a large number of pristine fragments, reasons that led to its classification as a World Heritage Site by UNESCO (IUCN, 1999). Most of the Laurisilva area is included in the Madeira Natural Park and benefits from regional, na- tional and international legislation (Menezes et al., 2005a). Further, Madeira Laurisilva is a priority habitat under the Habitats Directive and was designated a Natura 2000 Network Site. The upper margin of Laurisilva and above (between 1400-1650 m) is dominated by a scrubland where two Erica species (E. arborea and E. platycodon maderincola) are the dominant plants. Above 1650 m, the vegetation is com- posed by a mosaic of three different altitudinal rupicolous communities, mostly represented by small shrubs or herb species (e.g., Aeonium glandulosum, Deschampsia maderensis, Parafestuca albida, Thy- mus micans). In Porto Santo and Desertas, the dominant plant cover is composed by herbaceous commu- nities, but several sclerophyllous and thermophilous tree and shrub species (like Artemisia argentea, Echium nervosum, Euphorbia piscatoria, Jasminum odoratissimum, Olea europaea maderensis) are also found in vegetation mosaics. Detailed information on the native vegetation of Madeira archipelago, particu- larly Laurisilva, can be found elsewhere (Neves et al., 1996; Capelo, 2004). In Madeira and Porto Santo a fraction of the land surface is also covered with planted forest (Uva, 2008) (Fig. 2; Plate I). In Porto Santo, pine (Pinus halepensis) and cypress (Cupressus macrocarpa) for- ests were planted on mountaintops and on the southwestern tip aiming to minimize the effects of soil ero- sion and combat desertification. In Madeira, most of the cultivated forest is distributed throughout the south slope at low and mid altitudes and was planted mostly for economic reasons. The dominant plantations are (Eucalyptus spp.) and pine (Pinus spp.), but Acacia (Acacia spp.) and nd chestnut (Castanea sativa), Revista IDE@ - SEA, nº 6B (30-06-2015): 1–20. ISSN 2386-7183 2 Ibero Diversidad Entomológica @ccesible www.sea-entomologia.org/IDE@ I ntroduction The biodiversity of terrestrial arthropods in Madeira and Selvagens Manual ▲ Figure 1. The islands and islets of Madeira archipelago with some geographic notes (adapted from Clara Gaspar’s original in Fernández-Palacios, 2010). ◄Figure 2 . Main land uses in Madeira and Porto Santo. Maps drawn by Enésima Mendonça (source DROTA). though more localized, are also important. In the last years, cultivated forest abandonment and the impact of the pine wood nematode are leading to significant changes in the scenario of Madeira planted forests. Since its colonization by man, the natural plant cover of Madeira archipelago suffered a progressive destruction leading to a drastic panorama in many areas of Madeira and Porto Santo. In spite of consecu- tive efforts across centuries to control tree logging for timber and fuel, to stop the clearing of fields using fire and to limit the adverse effects of goats and sheep grazing, the situation has continued to worsen. It was not until the second half of the XXth century (between 1952-1974) that a major program to recover the plant cover of Madeira archipelago was carried by the Forestry Services (Andrada, 1990). This ambitious and multidisciplinary enterprise was structured in several modalities, among which the establishment of nurseries for native plants, forest restoration activities and soil protection initiatives against erosion have played a determinant role. Further, the obligation to prevent past environmental harmful practices and the growing awareness of regional/national entities and of the general public for the urgent need to value and safeguard Madeira Natural Heritage led to an increasing willingness for the establishment of a protected area in Madeira Island. Thus, in 1982, the Natural Park of Madeira was created with the aim to conserve and enhance natural and cultural heritage, promote the sustainable use of natural resources and to foster the economic and social well-being of local communities. Presently, the network of protected areas of Madeira and Selvagens archipelagos comprehend the Selvagens Islands Natural Reserve, the Madeira Natural Park, the Garajau Partial Natural Reserve, the Desertas Islands Natural Reserve, the Rocha do Navio Natural Reserve and the Network of Marine Protected Areas of Porto Santo, together with other areas included in the Natura 2000 Network (Freitas et al., 2004, 2011; Menezes et al., 2004, 2005a, 2005b; Medeiros et al., 2010; see also http://www.pnm.pt/). Freshwater habitats are poorly represented in the archipelago, with the exception of Madeira Island which presents a complex hydrographic network with many streams and their subsidiaries having a very good water and habitat quality, particularly in areas near headwaters in northern Madeira. Downstream and near the mouth, most streams present a poorer water quality due to pollution (mostly organic) and physical disturbance of the environment (Hughes & Furse, 2001). Revista IDE@ - SEA, nº 6B (30-06-2015): 1–20. ISSN 2386-7183 3 Ibero Diversidad Entomológica @ccesible www.sea-entomologia.org/IDE@ I ntroduction The biodiversity of terrestrial arthropods in Madeira and Selvagens Manual Fig. 3. The islands and islets o f Selvagens archipelago with some geographic notes (adapted from Clara Gaspar’s original in Fernández-Palacios, 2010). In Madeira archipelago, the human population is over 260,000 people (DREM, 2014). Most people live in Madeira Island, particularly in the southern localities of the island where most infrastructures, indus- tries and services are established. Only around 5,000 people have been reported from Porto Santo and most live in the capital Vila Baleira. Besides the resident human population, the archipelago of Madeira receives around a million visitors a year that come to Madeira in search of good weather and to engage in a variety of cultural activities and tours to natural habitats (e.g., bird and whale watching, mountain hiking, levada walks). During the last decade there has been massive construction in several areas of Madeira, particularly on the areas surrounding Funchal, and the network of paved roads expanded considerably leading to a higher mobility of people and goods throughout the island and the possibility to reach once inaccessible areas. The archipelago of Selvagens is composed of Selvagem Grande, Selvagem Pequena and Ilhéu de Fora (Fig. 3) and lies 175 km north to the Canary Islands. These islands are among the oldest of Macaronesia (27 My) and represent the last stages of the island life-cycle, when islands become more flat due to erosion and tend to disappear below sea level (Fernández-Palacios & Whittaker, 2010). The ve- getation of Selvagens is dominated by xerophytic and halophytic herbs and small shrubs, including some endemic plants like two subspecies of Lobularia canariensis and the natives Astydamia latifolia, Frankenia laevis, Limonium papillatum, Schizogyne sericea and Suaeda vera. In spite of the attempts of colonization, the lack of potable water and the harsh environment were in- surmountable obstacles for human settlement in Selvagens. Some geographic characteristics of Madeira and Selvagens archipelagos are summarized in figures 1 and 3. Further, information on these archipela- gos can be found in specialized literature (see Menezes et al., 2004, 2005a, 2005b; Fernández-Palacios, 2010; Freitas et al., 2011; Ulbrich, 2014 and references therein). 2. History of the knowledge on terrestrial arthropods The first registered visits of naturalists to the archipelago of Madeira date back to the final stages of the seventeenth century, more precisely by the British physician and naturalist Hans Sloane in 1687. Never- theless, we know that apparently the first insect samples were only collected in 1768 during Captain James Cook first expedition which had the confidential purpose from the British Admiralty of finding the hypothetic Terra Australis Incognita, although other scientific activities were intended, as the study of the fauna and flora of newly discovered territories. The scientific team on board HMS Endeavour was led by the British aristocrat botanist Sir Joseph Banks (1743-1820) and the Swedish botanist Daniel Carlsson Solander (1733-1782). The team also included Herman Dietrich Spöring (1733-1771), a Finnish native and gifted instrumentalist who was put in charge of scientific equipment maintenance and of cataloguing the expedition findings. En route to Brazil and according to Banks’ expedition diary, the Endeavour anchored in Funchal bay on the 12th of September. The following day Banks and Solander were welcomed by the British Consul on the island, Mr Cheap, who offered them shelter and all the resources and men to help in the island’s explo- ration. During the next 5 days they searched for plants, shells, fishes and insects. Given the limited time available the exploration summed up to barely 3 miles surrounding Funchal and it appears that the results were somewhat disappointing given that Banks wrote in his diary that “The season of the year was un- doubtedly the worst for both plants and insects”. And what about the fate of these first insect samples collected in Madeira? It is known that Johan Christian Fabricius (1745-1808), a Danish botanist and entomologist, previously a student of Carl Lin- naeus, regularly visited London during summer, where he studied many entomological collections of Eng- lish naturalists such as Banks and Drury. It was probably on one of these occasions that Fabricius had access to specimens of Banks’ collection from Madeira and as a result he described several endemic species in his Entomologia Systematica Emendata et Aucta, published between 1792 and 1799, namely the satyrine butterfly Pararge xiphia, the beetles Meladema lanio and Ellipsodes glabrata and the ant-lion Dystoleon catta. Revista IDE@ - SEA, nº 6B (30-06-2015): 1–20. ISSN 2386-7183 4 Ibero Diversidad Entomológica @ccesible www.sea-entomologia.org/IDE@ I ntroduction The biodiversity of terrestrial arthropods in Madeira and Selvagens Manual Plate I. Some habitats of Madeira archipel- ago: A. coastal vegetation at Ilhéu Chão; B. grassland cover in Porto Santo; C. grassland with interspersed shrubs at Ilhéu Chão; D. Laurisilva. A-C: © A.R.M. Serra- no; D: C. Viveiros. Revista IDE@ - SEA, nº 6B (30-06-2015): 1–20. ISSN 2386-7183 5 Ibero Diversidad Entomológica @ccesible www.sea-entomologia.org/IDE@ I ntroduction The biodiversity of terrestrial arthropods in Madeira and Selvagens Manual Several other naturalists visited Madeira after Banks and Solander, but it was only in the middle of the nineteenth century that the study of insects in the archipelago was given a notable advance in quantity and quality by the hand of Thomas Vernon Wollaston (1822-1878). Young Wollaston, with a degree from Cambridge and being a member of the famous Linnean and Cambridge Philosophical Societies, was 24 years old when he was diagnosed with tuberculosis. As was common at that time doctors recommended a prolonged stay in Madeira for convalescence. On his first visit to this island, from October 1847 to May 1848, Wollaston becomes friend of Reverend Richard Thomas Lowe (1822-1878) a notable British natural- ist and leader of the Anglican Church in Madeira. Lowe, himself very interested in plants and molluscs, convinces Wollaston to collect insects and shells, which he does without a clear purpose, just to pass time in a remote island. The return trip to England affects his health so badly that Wollaston decides for a sec- ond stay in Madeira six months later. This time Wollaston has decided to collect insects and publish the results, and so, from November 1848 to June 1849, he does collections in Madeira, Porto Santo and De- sertas. Next year he is back a third time and stays from May to September with an unstoppable enthusi- asm; equipped with a tent, he sampled systematically the main island. The sheer volume of data gathered results in his majestic work Insecta Maderensia published in 1854, where he lists more than 500 species of Coleoptera, and three years later followed the Catalogue of the coleopterous insects of Madeira in the collection of the British Museum, which provides an overview of beetle species distribution in Madeira archipelago. In 1865 Wollaston publishes Coleoptera Atlantidum, a catalogue of all species known at the time from the archipelagos of Madeira, including the Salvage islands, and the Canary Islands. Until his early death in 1878, Wollaston visits Madeira archipelago several more times and publishes several addi- tional books on the coleopteran fauna of other Atlantic archipelagos, namely Cape Verde (1867) and Saint Helena (1877). This impressive legacy of scientific production includes 8 books and 33 articles totalling more than 3000 pages describing more than 1000 species of beetles and other insects (Machado, 2006). Wollaston’s work was extremely important in directing the international scientific community’s atten- tion to a still under explored region with an entomological fauna promising many new species to be de- scribed. Until the end of the nineteenth century and the beginning of the twentieth many more entomolo- gists and naturalists visited the archipelago and made important contributions, although it was only near the middle of the twentieth century that the first scientific expedition with the main purpose of collecting arthropods was organised. In 1935, between July and August, a team from the Swedish Museum of Natu- ral History led by zoologist Carl Olov Lundblad (1890-1970), an aquatic mite specialist, sampled an enor- mous quantity of insects, spiders, ticks, mites and pseudoscorpions. All this material was subsequently studied by many specialists and the results were published in several volumes of the journal Arkiv för Zo- ologi between 1938 and 1958. Among the contributors, the hemipterologist William Edward China (1895- 1979) authored the most complete catalogue on Madeira Terrestrial Hemiptera (China, 1938), which in- cluded also poorly studied material collected by Wollaston and deposited in the British Museum, where China was assistant keeper. Lundblad himself published an extensive list of Coleoptera and updated the knowledge on this insect group (Lundblad, 1958). Richard Frey (1886-1965), a Finnish entomologist, together with Ragnar Storå and Carl Cedercreutz organised an expedition to Madeira and the Azores, the “Iter entomologicum et botanicum ad insulas Ma- deiram et Azores anno 1938”. Frey, particularly interested in Diptera, published his findings, including the discovery of new species, a few years later in a paper in Commentationes Biologicae (Frey, 1949). Almost two decades later, in December 1957, two members of the Royal Entomological Society, A.E. Gardner and Eric W. Classey, stayed in Madeira to collect insects. Although the time of the year was not the best for this activity, they managed to collect more than a thousand specimens from different insect groups, including series of many rare species. They published their results in 1960 and 1962 in two articles of the Proceedings of the South London Entomological and Natural History Society. More or less at the same period, Håkan Lindberg, a professor at the University of Helsinki, organized two expeditions to the entire archipelago, the first in June/July 1957 and the second in April/May 1959. Most of the material collected in both expeditions was deposited in the Finnish Museum of Natural History and the results were published in at least two volumes of the Societas Scientarum Fennica – Commenta- tiones Biologicae, one by Lindberg himself in 1961 totally dedicated to the Hemiptera and a second one in 1963, with 20 articles by several authors, on the Coleoptera found by the expeditions. The 1961 volume, entitled “Hemiptera Insularum Madeirensium”, catalogues all the Heteroptera, Cicadomorpha and Ful- goromorpha collected during the expeditions. This volume also includes two contributions of German mirid specialist Eduard Wagner (1896-1978), one of them an extensive revision of genus Chinacapsus Wagner, 1961, endemic from Madeira, and genus Lindbergocapsus Wagner, 1961, endemic from the Canary Is- lands. Also based on material collected during Lindberg’s expeditions, Marina Mikhailovna Loginova pub- lishes in 1976 the first extensive account on the psyllids of Madeira. The paper “Psyllids of the Canary Islands and Madeira” lists 29 species, 20 of them as new to science. It seems that Atlantic Islands were a sought of destination by Nordic entomologists and zoologists as in 1957 another expedition, this time Swedish, was organized by two Lund University professors, Per Brinck and Erik Dahl. These scientists stayed in the Azores between February and April and in Madeira on the second half of April. Most of the material collected in this expedition is deposited in the Zoological Museum of Lund University and an important part of the results were published in the 1960 volume of the Boletim do Museu Municipal do Funchal. Between February and March 1976 the Natural History Museum of Tenerife (Spain) organized a sci- entific expedition, “Agamenon 76”, to study the zoology, botany and geology of the Selvagens. The results were published in 1978, in a single volume of Aula de Cultura de Tenerife, entitled “Contribución al estudio de la Historia Natural de las Islas Salvajes”. Revista IDE@ - SEA, nº 6B (30-06-2015): 1–20. ISSN 2386-7183 6 Ibero Diversidad Entomológica @ccesible www.sea-entomologia.org/IDE@ I ntroduction The biodiversity of terrestrial arthropods in Madeira and Selvagens Manual Figure 4. The description of endemic terrestrial arthropod taxa (S) of Madeira and Selvagens archipelagos per decade (bars) and its cumulative value across time (diamonds). Three landmarks are signaled in the graph: the description of one of the first endemics, Pararge xiphia (Fabricius, 1775); the publication of Insecta Maderensia by Wollaston in 1854 and the recent publication of the checklist of fauna and flora from Madeira and Selvagens archipelagos (photo by AMF Aguiar). The eminent Portuguese aphidologist Fernando Albano Ilharco, a researcher of the National Agro- nomic Station (Portugal), organized two expeditions in 1966 and 1980 with financial support from the Calouste Gulbenkian Foundation. During these expeditions the main inhabited islands of Madeira and Porto Santo were visited as well as Deserta Grande on the second trip. The material collected is deposited in the National Agronomic Station and the results of the study were published in several papers in the journals Agronomia Lusitana, Boletim da Sociedade Portuguesa de Entomologia and Boletim do Museu Municipal do Funchal. Also in 1980, the first multidisciplinary Portuguese scientific expedition to both Madeira and Sel- vagens archipelagos was organized by a team of Portuguese zoologists from the Lisbon Faculty of Sci- ences and from the National Museum of Natural History and Science. The so called “Zoological Mission”, was held between April and May, and was directed to sample insects and birds. Several hundreds of specimens from 15 insect orders were sampled during this expedition and the results were mainly pub- lished in the journals Bocagiana, Boletim do Museu Municipal do Funchal and Arquivos do Museu Bocage during the following decade. Until 1980, various taxonomic experts across Europe like Reinhard Remane, Rauno Linnavuori and Richard Strassen, received specimens for study from Madeira and have collabo- rated in the hard task of describing and cataloguing the terrestrial arthropod fauna of these islands. During the following decades, both the growing interest on Madeira biodiversity and the relative ease in traveling to these islands, potentiated the visit of many taxonomic experts. As a consequence, the knowledge on the terrestrial arthropod biodiversity of Madeira increased considerably. Thus, among oth- ers, we want to highlight the extraordinary contributions made by Dieter Erber (Coleoptera), Henrik Enghoff (Diplopoda), Joerg Wunderlich (Araneae), Luis Subías (Acari), Marcos Báez (Diptera), Ole Karsholt (Lepi- doptera), Volker Assing (Coleoptera) and their colleagues. Further, it should be stressed that during this period a few entomological expeditions were also carried out to Selvagens archipelago leading to new findings: a Manchester University expedition in 1984 and the scientific expedition “Macaronesia 2000”, organized by the Natural History Museum of Tenerife in 1999. The first results of this latter expedition were published in the 2001 volume of Revista de la Academia Canaria de Ciencias. The description of new endemic terrestrial arthropods from Madeira and Selvagens has been rela- tively high since 1980, although it may seem less impressive if compared with the outstanding work of Thomas Wollaston during the 1850s (Fig. 4). Nevertheless, only as recently as 2008 did the global knowledge on the terrestrial arthropods of the archipelagos of Madeira and Selvagens become available in one source, which lists 3891 species and subspecies. This was the result of a team effort of more than 70 entomologists coordinated by one of us (P.A.V. Borges) in a project led by the Azores University and funded by the Madeira environmental entities. The checklist of Madeira and Selvagens taxonomic biodiversity was followed by two important works where conservation priorities were identified within the context of Macaronesia aiming to simultaneously protect native species and to control invasive species (Martín et al., 2008; Silva et al., 2008). Four endemic arthropods - Chrysolina fragariae, Deucalion oceanicum, Gonepteryx maderensis, Paradeucalion deserta- rum - were identified as in urgent need for conservation measures in Madeira and Selvagens, and it was stressed the haste to foster population control of several noxious introduced arthropods. More recently, our team coordinated a book with contributions from 26 authors where some recent findings on Madeira and Macaronesia terrestrial arthropods were discussed and prospects for future work on biodiversity, ecologi- cal and evolutionary issues were presented (Serrano et al., 2010). Revista IDE@ - SEA, nº 6B (30-06-2015): 1–20. ISSN 2386-7183 7 Ibero Diversidad Entomológica @ccesible www.sea-entomologia.org/IDE@ I ntroduction The biodiversity of terrestrial arthropods in Madeira and Selvagens Manual In the field of applied entomology, Madeira has experienced a steady sequence of biological control attempts of insect pests through the introduction of exotic predators and parasitoids. Although not always successful, these events were very important as technology transfer occurrences. In the final of 1930’s, the coccinellid Rodolia cardinalis was locally bred in captivity to be released by the local farmers against the exotic coccid Icerya purchasi a serious pest of citrus on those days. The predator is still active today and the coccid populations are controlled to the point of being considered an unimportant plant pest. In the 1970’s, the local Agricultural Services imported from France (Antibes Research Station – INRA) a small quantity of the eulophid parasitoid Cales noacki for an attempt (successful) of innoculative release against the Citrus Woolly Whitefly, Aleurothrixus floccosus. In the middle 1990´s, under a EU funded IPM program against several citrus insect pests, another successful introduction was made, this time from Israel: the encyrtid parasitoid Ageniaspis citricola was released to control the Citrus Leaf Miner, Phyllocnistis citrella. Some years later, downtown Funchal struggles with severe infestations of the decorative blue jacarandas by the lantana bug Insignorthezia insignis. It is decided to implement a new biological control program and contacts are made with the Commonwealth Agricultural Bureau International through which was imported from Kenya, in 2002, a small quantity (<200 adult specimens) of the coccinellid predator Hyperaspis pan- therina. Part of this sample was released and the remaining specimens were used to initiate a breeding colony for mass creation. Locally-implemented changes to the breeding methodology of this coccinellid led to a 75% increase in the production of adult beetles. The new breeding facility created for this purpose remained active for 3 years and during this period more than 110,000 coccinellids were released in Fun- chal and its surroundings (Félix et al., 2004, 2005). Perhaps the most complex and expensive program developed in Madeira against an insect pest was the application of SIT (Sterile Insect Technique) to control the Mediterranean Fruit Fly, Ceratitis capitata. Also funded by the EU under the Program POSEIMA/Madeira, a factory was constructed and started the production of sterilised fruit flies in 1996. The success of this technique requires a massive production of insects at relative low cost for which, at the time, this was the first and only factory in Europe with a weekly production capacity of 50 million sterilised males. This factory was the first to use a genetically improved strain of C. capitata, the tsl strain (temperature sensitive lethal), that enables the elimination of the females in the egg or neonate larva states and consequently the production of only sterilised males (Pereira, 1999). The factory stayed in production for 15 years sustaining area-wide releases in Madeira and Porto Santo islands and also exported surplus pupae to Israel and Morocco. Finally, it is also worth mentioning that three insect groups, aquatic macroinvertebrates, ground bee- tles and Drosophila species, have also been studied with some detail from the perspectives of applied ecology and evolutionary ecology, showing the usefulness of Madeira arthropods as model organisms. Aquatic macroinvertebrates were used as bioindicators to evaluate water quality of Madeira Island streams contributing to a better understanding of the ecological integrity of the hydrographic network and leading to interesting taxonomic findings (Hughes et al., 1998; Hughes & Furse, 2001; Hughes, 2006). Ground bee- tles have been used as biodiversity and ecological bioindicators to assess the value of different Laurisilva patches for nature conservation (Serrano & Aguiar, 1997, 1998; Boieiro et al., 2013b). On the other hand, various genetic, ecological and ethological studies on two sister species of Drosophila - the endemic D. madeirensis and the native D. subobscura – have shed light on the mechanisms of species diversification and reproductive isolation in closely related species (Khadem & Krimbas, 1996; Rego et al., 2006). Any entomologist engaged or interested in studying insects from these islands must be aware that presently at least four institutional insect collections exist in Madeira. In Funchal we can find the collection of the Natural History Museum of Funchal where a small selection of insects includes the public exhibition, but the main collection has limited access. The Biology Department of Madeira University located in the Penteada Campus has its own entomological collection resulting from the samples gathered in a variety of projects carried throughout the archipelago. The remains of the historical Seminary Museum collection, which resulted from the dedicated work of several priests, were recently recovered and catalogued and are now preserved in a small natural history museum housed at the Funchal Botanical Gardens. The fourth entomological collection is that of the Madeira Agricultural Laboratory, located near Camacha, which con- tains nearly 30,000 specimens, and in spite of its general value, is a major reference for information on species with economic impact. Other institutions, both in Continental Portugal and abroad, also have ar- thropod collections from Madeira and Selvagens archipelagos, including type material, that resulted from individual or collective expeditions, or were given away or sold by their owners. 3. The biodiversity of terrestrial arthropods The archipelagos of Madeira and Selvagens, as a whole, present a considerable diversity in species and endemic life forms. The checklist of terrestrial arthropods of theses archipelagos was recently updated following a thorough survey of literature, revision of specimens from natural history collections and also included unpublished information (Borges et al., 2008a). This task could only be accomplished through the cooperation of many taxonomic experts and is now a major reference on the biodiversity of Madeira and Selvagens archipelagos. The number of terrestrial arthropod taxa reported from Madeira and Selvagens archipelagos is re- spectively 3801 and 201, among which there is a significant number of endemics (Borges et al., 2008b) (see Table I; Fig. 5; Plate II). Madeira, the largest island, with a complex orography and highest number of habitat-types, clearly stands out both in species richness and in number of endemic taxa from the other islands of the two archipelagos. Nevertheless, we must also take in consideration that Madeira’s biodiver- sity has been studied in more detail since this island has been a target for several natural history expedi- tions and many visits from worldwide taxonomic experts (see above section). Revista IDE@ - SEA, nº 6B (30-06-2015): 1–20. ISSN 2386-7183 8 Ibero Diversidad Entomológica @ccesible www.sea-entomologia.org/IDE@ I ntroduction The biodiversity of terrestrial arthropods in Madeira and Selvagens Manual Table I. Number of terrestrial arthropod taxa from different taxonomic groups in the islands of Madeira and the Selvagens, and for both archipelagos (Total). The total number of terrestrial arthropod taxa is pre- sented at the bottom. In specific situations, taxa were reported to Madeira archipelago without indication of the island where the collection was made. Class/Order Madeira Porto Santo Desertas Selvagens Total Arachnida 301 54 15 47 338 Acari: Astigmata 3 0 0 0 3 Acari: Ixodida 2 0 0 0 9 Acari: Mesostigmata 5 0 0 0 5 Acari: Oribatida 48 0 0 2 50 Acari: Prostigmata 62 0 0 0 62 Araneae 164 48 11 38 183 Opiliones 2 0 0 1 3 Pseudoscorpiones 15 6 4 6 23 Malacostraca 50 3 2 1 57 Maxillopoda 4 0 0 0 4 Ostracoda 4 0 0 0 4 Chilopoda 19 4 6 2 21 Diplopoda 54 7 3 2 60 Pauropoda 10 0 0 0 10 Symphyla 3 0 0 0 3 Collembola 75 24 0 0 87 Diplura 1 0 0 0 1 Protura 9 0 0 0 9 Insecta 3.019 676 279 149 3.297 Blattodea 14 2 1 0 14 Coleoptera 881 274 130 66 1040 Dermaptera 12 4 1 4 12 Diptera 538 48 16 9 555 Embioptera 1 2 2 0 2 Ephemeroptera 3 0 0 0 3 Hemiptera 481 124 47 14 522 Hymenoptera 593 28 28 9 610 Isoptera 3 0 0 0 3 Lepidoptera 315 137 26 24 331 Mantodea 1 0 0 0 1 Microcoryphia 2 1 0 0 3 Neuroptera 14 4 1 0 15 Odonata 5 5 1 2 6 Orthoptera 26 6 5 5 28 Phthiraptera 8 4 9 5 13 Psocoptera 40 6 0 4 45 Siphonaptera 6 9 1 2 11 Strepsiptera 1 0 0 0 1 Thysanoptera 57 19 10 2 62 Trichoptera 13 0 0 0 13 Zygentoma 5 3 1 3 7 Artrópodos terrestres 3.549 768 305 201 3.891 The terrestrial arthropod fauna of Madeira and Selvagens presents a high proportion of native taxa (68%), but the number of introduced species is already considerable and it is expected to keep rising due to the increasing transportation of people and goods from various points of the world (Pombo et al., 2010a). The percentage of endemic taxa is appreciable, and it is worth mentioning that many endemic taxa of Madeira and Selvagens archipelagos are single-island endemics (i. e., species restricted to just one island) or are restricted to a group of a few small islands and islets (Desertas or Selvagens) (Fig. 5). Further, there is a considerable number of native species that besides occurring in Madeira or Desertas archipelagos can only be found in Azores and/or Canaries (i.e., they are exclusive of Macaronesia). In spite of the high number of species reported to Madeira and Selvagens archipelagos, the current knowledge on the taxonomic biodiversity of these islands is far from complete as was stressed in a recent study (Lobo & Borges, 2010). New findings (even in well studied arthropod groups) made in the last few years confirm this assumption (Caldara & Aguín-Pombo, 2008; Donabauer, 2008; Esser, 2008; Schimmel, 2008; Serrano et al., 2009; Wrase, 2010; Machado, 2012; Kratochvil & Scheuchl, 2013; Crespo et al., 2014; Reboleira & Enghoff, 2014; Rego et al., 2014; Rota et al., 2014). So, major efforts should be en- dorsed to survey less explored habitats and regions, and to focus on still understudied hyperdiverse ar- thropod groups like Acari, Araneae, Diptera and Hymenoptera (Lobo & Borges, 2010). Among the different groups of terrestrial arthropods recorded in Madeira and Selvagens archipela- gos, the Coleoptera clearly dominate in number of species and endemics followed by Hymenoptera, Revista IDE@ - SEA, nº 6B (30-06-2015): 1–20. ISSN 2386-7183 9 Ibero Diversidad Entomológica @ccesible www.sea-entomologia.org/IDE@ I ntroduction The biodiversity of terrestrial arthropods in Madeira and Selvagens Manual Figure 5. Number of endemic taxa of terrestrial arthropods in islands of the Madeira and Selvagens archipela- gos. Endemics restricted to each island or island group (SIE) are highlighted in dark green. Figure 6. Proportion of endemic taxa from the different terrestrial arthropod groups. Figure 7. The number of endemic taxa (S) of ter- restrial arthropod genera that have diversified (> 10 taxa) in Madeira and Selvagens archipelagos (photos by A.M.F. Aguiar and A.R.M. Serrano). Revista IDE@ - SEA, nº 6B (30-06-2015): 1–20. ISSN 2386-7183 10 Ibero Diversidad Entomológica @ccesible www.sea-entomologia.org/IDE@ I ntroduction The biodiversity of terrestrial arthropods in Madeira and Selvagens Manual Plate II. Endemic arthropods of Madeira archipelago: A. the termite Postelectrotermes praecox; B. the mayfly Cloeon peregrinator; C. the butterfly Hipparchia maderensis; D. the bee Amegilla maderae; E. the ground beetle Eurygnathus latreillei; F. the darkling beetle Hadrus sp. A, C, E, F: © A.R.M. Serrano; B; © A.M.F. Aguiar; D: © C. Rego. Diptera, Lepidoptera and Hemiptera (Table I; Fig. 6). Together these hyperdiverse insect groups represent nearly 77% of the terrestrial arthropod endemic taxa diversity, but both Araneae and Acari are also well represented.