979 resultados para Cryptic species


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A total of 352 specimens were analyzed to achieve the different aims of this thesis. 255 central-northern Adriatic specimens of S. solea and S. aegyptiaca were molecularly analysed using microsatellite locus Sos(AC)40 and 205 also morphologically due to evaluate the abundance and the distribution of the cryptic species S. aegyptiaca and to confirm morphologic analyses. Morphological and molecular analyses comparated show a correspondence of 96%. A combined morphologic approach could be proposed to apply multiple criteria on the analyzed external morphological keys. The Adriatic Egyptian soles may lives in shallow waters (up 30 m) and in brackish lagoon. 127 samples of Adriatic common sole added to 326 samples of previous studies showed, using mitochondrial marker (CytB), that the Adriatic Sea as contact zone between Tyrrhenian and Aegean Sea, the divergence within the Adriatic Sea is low but significant between central-north and south, with a longitudinal strong gene flow in central-northern side. It’s also showed as in the Adriatic Sea two near-panmictic populations of common sole exist.

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Die Phylogenie der Westpaläarktischen Langohren (Mammalia, Chiroptera, Plecotus) – eine molekulare Analyse Die Langohren stellen eine Fledermausgattung dar, die fast alle westpaläarktischen Habitate bist zum Polarkreis hin besiedeln und in vielerlei Hinsicht rätselhaft sind. In der Vergangenheit wurden zahlreiche Formen und Varietäten beschrieben. Trotzdem galt für lange Zeit, dass nur zwei Arten in Europa anerkannt wurden. Weitere Arten waren aus Nordafrika, den Kanaren und Asien bekannt, aber auch deren Artstatus wurde vielfach in Frage gestellt. In der vorliegenden Dissertation habe ich mittels molekularer Daten,der partiellen Sequenzierung mitochondrialer Gene (16S rRNA und ND1), sowie der mitochondrialen Kontrollregion, eine molekular Analyse der phylogenetischen Verwandtschaftsverhältnisse innerhalb und zwischen den Linien der westpaläarktischen Langohren durchgeführt. Die besten Substitutionsmodelle wurden berechnet und phylogenetische Bäume mit Hilfe vier verschiedener Methoden konstruiert: dem neighbor joining Verfahren (NJ), dem maximum likelihood Verfahren (ML), dem maximum parsimony Verfahren (MP) und dem Bayesian Verfahren. Sechs Linien der Langohren sind genetisch auf einem Artniveau differenziert: Plecotus auritus, P. austriacus, P. balensis, P. christii, P. sardus, und P. macrobullaris. Im Falle der Arten P. teneriffae, P. kolombatovici und P. begognae ist die alleinige Interpretation der genetischen Daten einzelner mitochondrialer Gene für eine Festlegung des taxonomischen Ranges nicht ausreichend. Ich beschreibe in dieser Dissertation drei neue Taxa: Plecotus sardus, P. kolombatovici gaisleri (=Plecotus teneriffae gaisleri, Benda et al. 2004) and P. macrobullaris alpinus [=Plecotus alpinus, Kiefer & Veith 2002). Morphologische Kennzeichen, insbesondere für die Erkennung im Feld, werden hier dargestellt. Drei der sieben Arten sind polytypisch: P. auritus (eine west- und ein osteuropäische Linie, eine sardische Linie und eine aktuell entdeckte kaukasische Linie, Plecotus kolombatovici (P. k. kolombatovici, P. k. gaisleri und P. k. ssp.) und P. macrobullaris (P. m. macrobullaris und P. m. alpinus). Die Verbreitungsgebiete der meisten Arten werden in dieser Arbeit erstmals ausschließlich anhand genetisch zugeordneter Tiere dargestellt.Die Untersuchung der ökologischen Einnischung der nun anerkannten Formen, insbesondere in Gebieten sympatrischer Verbreitung, bietet ein spannendes und lohnendes Feld für zukünftige Forschungen. Nicht zuletzt muss sich die Entdeckung eines beachtlichen Anteils kryptischer Diversität innerhalb der westpaläarktischen Langohren auch bei der Entwicklung spezieller Artenschutzkonzepte widerspiegeln.

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The relationship and phylogeny of the western Palearctic harvestmen family Trogulidae is investigated. The traditional system of seven genera and approximately 40 species appeared to be artificially composed but a phylogenetic approach and a comprehensive revision has long been sought after. Species are poorly characterised due to their uniform morphology and species evaluation is furthermore complicated by the variability of the few characters used for species delineation. To meet these demands a molecular genetic analysis is accomplished using the nuclear 28S rRNA gene and the mitochondrial cytochrome b gene. This analysis incorporates most genera and species of Trogulidae as well as a comprehensive set of Nemastomatidae and Dicranolasmatidae as outgroup taxa. Phylogenetic results of Bayesian analysis, Maximum Parsimony, Maximum Likelihood and Neighbor Joining are compared with distributional data, morphological characters and results of canonical discriminant analysis of morphometric characters and general congruence of these data sets is shown. To demonstrate the applicability of this method the revision of two species-groups within Trogulus is set out in detail. The Trogulus hirtus species-group and the Trogulus coriziformis species-group are revised. The former is in the central and north-western Balkan Peninsula. T. tricarinatus ssp. hirtus is raised to species level and four new species are described (T. karamanorum [man.n.], T. melitensis [man.n.], T. pharensis [man.n]; T. thaleri [man.n.]). The Trogulus coriziformis species-group is confined to the western Mediterranean area. T. coriziformis, T. aquaticus are re-described, T. cristatus and T. lusitanicus are re-established and four species are described as new (T. balearicus, T. huberi, T. prietoi, T. pyrenaicus). In both species-groups two further cryptic species probably exist but were not described. The species groups are shown to represent different phylogenetic levels and this information is used for the revisional work on the genus Trogulus as well as for the generic system of Trogulidae. Family status of Dicranolasmatidae is rejected and Dicranolasma is shown to be best incorporated within Trogulidae. Calathocratus, Platybessobius and Trogulocratus appear to be polyphyletic and are best to be united within Calathocratus, the oldest name of this set. The cryptic diversity within Trogulidae, especially in Trogulus and the composed genus Calathocratus rates to 150-235% and is thereby remarkably high for a group of the generally well researched European fauna. Genetic features of the group such as heteroplasmy, the possibility of major gene rearrangements and usability of the cytochrome b gene for phylogenetic studies in Opiliones are outlined.

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The family Hyalidae comprises more than one hundred species, distributed worldwide. They are common and abundant in the littoral and shallow sublittoral habitats and they play an important role in the coastal food chain. Most studies about this family were dealing with taxonomy and ecology, while very little is known about phylogenetic relationship among genera and species. In the present study we aim to achieve the first approach of the phylogenetic patterns of this family in NE Atlantic Ocean and Mediterranean Sea, and to perform the first insight into the phylogeography Apohyale prevostii along both the North Atlantic coasts. In order to do that, eight species belonging to the genera Apohyale, Hyale, Serejohyale and Protohyale were investigated using the mitochondrial COI-5P barcode region. Specimens were collected along European and Moroccan Atlantic rocky shores, including Iceland, the British Isles, Macaronesia and in the Mediterranean Sea. Sequences of A. prevostii, from the NW Atlantic Ocean, available in BOLD and GenBank, were retrieved. As expected, phylogenetic analyses showed highly-divergent clades, clearly discriminating among different species clusters, confirming their morphology-based identifications. Although, within A. perieri, A. media, A. stebbingi, P. (Protohyale) schmidtii and S. spinidactylus, high genetic diversity was found, revealing putative cryptic species. The clade of A. prevostii and A. stebbingi appears well supported and divided from the other two congeneric species, and P. (Protohyale) schmidtii shows a basal divergence. The north-western Atlantic coasts were recently colonized by A. prevostii after the last glacial maximum from the European populations showing also a common haplotype in every population analysed. The use of the COI-5P as DNA barcode provided a good tool to underline the necessity of a revision of this emblematic family, as well as to discern taxonomically the possible new species flagged with this molecular device.

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Molecular methods provide promising tools for routine detection and quantification of toxic microalgae in plankton samples. To this end, novel TaqMan minor groove binding probes and primers targeting the small (SSU) or large (LSU) ribosomal subunit (rRNA) were developed for two species of the marine dinoflagellate genus Alexandrium (A. minutum, A. tamutum) and for three groups/ribotypes of the A. tamarense species complex: Group I/North American (NA), Group II/Mediterranean (ME) and Group III/Western European (WE). Primers and probes for real-time quantitative PCR (qPCR) were species-specific and highly efficient when tested in qPCR assays for cross-validation with pure DNA from cultured Alexandrium strains. Suitability of the qPCR assays as molecular tools for the detection and estimation of relative cell abundances of Alexandrium species and groups was evaluated from samples of natural plankton assemblages along the Scottish east coast. The results were compared with inverted microscope cell counts (Utermöhl technique) of Alexandrium spp. and associated paralytic shellfish poisoning (PSP) toxin concentrations. The qPCR assays indicated that A. tamarense (Group I) and A. tamutum were the most abundant Alexandrium taxa and both were highly positively correlated with PSP toxin content of plankton samples. Cells of A. tamarense (Group III) were present at nearly all stations but in low abundance. Alexandrium minutum and A. tamarense (Group II) cells were not detected in any of the samples, thereby arguing for their absence from the specific North Sea region, at least at the time of the survey. The sympatric occurrence of A. tamarense Group I and Group III gives further support to the hypothesis that the groups/ribotypes of the A. tamarense species complex are cryptic species rather than variants belonging to the same species.

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Ecological studies have demonstrated the role of competition in structuring communities; however, the importance of competition as a vehicle for evolution by natural selection and speciation remains unresolved. Study systems of insular faunas have provided several well known cases where ecological character displacement, coevolution of competitors leading to increased morphological separation, is thought to have occurred (e.g., anoline lizards and geospizine finches). Whiptail lizards (genus Cnemidophorus) from the islands of the Sea of Cortez and the surrounding mainland demonstrate a biogeographic pattern of morphological variation suggestive of character displacement. Two species of Cnemidophorus occur on the Baja peninsula, one relatively large (Cnemidophorus tigris) and one smaller (Cnemidophorus hyperythrus). Oceanic islands in the Sea of Cortez contain only single species, five of six having sizes intermediate to both species found on the Baja peninsula. On mainland Mexico C. hyperythrus is absent, whereas C. tigris is the smaller species in whiptail guilds. Here we construct a phylogeny using nucleotide sequences of the cytochrome b gene to infer the evolutionary history of body size change and historical patterns of colonization in the Cnemidophorus system. The phylogenetic analysis indicates that (i) oceanic islands have been founded at least five times from mainland sources by relatives of either C. tigris or C. hyperythrus, (ii) there have been two separate instances of character relaxation on oceanic islands for C. tigris, and (iii) there has been colonization of the oceanic island Cerralvo with retention of ancestral size for Cnemidophorus ceralbensis, a relative of C. hyperythrus. Finally, the phylogenetic analysis reveals potential cryptic species within mainland populations of C. tigris.

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Anopheles é o gênero da família Culicidae mais estudado devido sua importância médica. Atualmente o gênero Anopheles compreende 472 espécies válidas que estão divididas em sete subgêneros. Os principais vetores de plasmódio da Malária no Brasil pertencem ao subgênero Nyssorhynchus, que inclui 39 espécies oficialmente reconhecidas e um número crescente de complexos de espécies crípticas que estão distribuídas em três Seções: Myzorhynchella, Albimanus e Argyritarsis. Atualmente a Seção Myzorhynchella é formada por seis espécies: An. lutzii, An. parvus, An. nigritarsis, An. guarani, An. antunesi e An. pristinus. Para o desenvolvimento da análise morfológica, observou-se material-tipo depositado em diferentes coleções, espécimes depositados na coleção entomológica da FSP/USP, além de outros obtidos em coletas realizadas durante o presente estudo em diferentes localidades do Brasil. As análises moleculares foram desenvolvidas a partir de espécimes obtidos nas coletas. Revisão taxonômica da Seção Myzorhynchella é apresentada, incluindo-se descrições de quatro novas espécies e redescrições das demais, informações sobre bionomia, importância médica, caracterização molecular, distribuição geográfica, estado de preservação do material-tipo, além de chaves de identificação de adultos, larva de quarto estádio e genitália masculina. Os resultados das análises filogenéticas utilizando sequências de ITS2, COI e Catalase indicam a existência de pelo menos doze espécies dentro da Seção Myzorhynchella, os espécimes que vêm sendo identificados como An. antunesi constitui um complexo formado por possíveis cinco espécies e aqueles de An. parvus e An. pristinus também podem representar complexos de espécies. As sequências de ITS2 podem ser utilizadas como marcador diagnóstico para espécies da Seção Myzorhynchella. Contudo, o estudo ainda demonstra que pouco se conhece sobre a diversidade de espécies de Anopheles que ocorrem em ambientes onde a malária ocorre em baixa endemicidade. Pelo número de espécies novas encontradas e pela escassez de trabalhos com espécies da Seção, fica evidente a necessidade de mais estudos.

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Introdução: A leishmaniose visceral (LV) é um importante problema de saúde pública no Brasil, com cerca 3000 mil casos notificados anualmente. Nos últimos anos, a LV tem ampliado sua distribuição em vários estados do país, associada principalmente aos processos socioambientais, antrópicos e migratórios. A LV é causada pela infecção com Leishmania infantum chagasi, transmitida, principalmente, por Lutzomyia longipalpis (Diptera: Psychodidae). Este flebotomíneo apresenta ampla distribuição nas Américas, todavia, evidências sugerem que se constitui em um complexo de espécies crípticas. A dinâmica de transmissão da LV é modulada por fatores ecológicos locais que influenciam a interação entre populações do patógeno, do vetor e dos hospedeiros vertebrados. Portanto, o estudo das variáveis associadas a esta interação pode contribuir para elucidar aspectos dos elos epidemiológicos e contribuir para a tomada de decisões em saúde pública. Objetivo: Avaliar parâmetros relacionados à capacidade vetorial da população de Lu. longipalpis presente em área urbana do município de Panorama, estado de São Paulo. Métodos: Foram realizadas capturas mensais durante 48 meses para avaliar a distribuição espaço-temporal de Lu. longipalpis e investigar a circulação de Le. i. chagasi. Também foram realizados os seguintes experimentos com o vetor: captura-marcação-soltura-recaptura para estimar a sobrevida da população e a duração do seu ciclo gonotrófico, a atratividade dos hospedeiros mais frequentes em áreas urbanas, a proporção de repasto em cão, infecção experimental e competência vetorial. Resultados: Observou-se que no município de Panorama, Lu. longipalpis apresentou as frequências mais elevadas na estação chuvosa (entre outubro e março), maior densidade em áreas com presença de vegetação e criação de animais domésticos, locais aonde também foi demonstrada a circulação natural de espécimes de Lu. longipalpis infectados com Le. i. chagasi. Além disto, foi corroborado que a população de Lu. longipalpis apresentou hábito hematofágico eclético, altas taxas de sobrevivência e que foi competente para transmitir o agente da LV. Nos experimentos de laboratório foi evidenciada a heterogeneidade na infecção de fêmeas de Lu. longipalpis desafiadas a se alimentarem em cães comprovadamente infectados por L. i. chagasi e o rápido desenvolvimento do parasita neste vetor natural. Conclusões. As observações do presente estudo corroboram a capacidade vetora de Lu. longipalpis para transmitir a Le. i. chagasi e ressaltam a importância da espécie na transmissão do agente etiológico da LV. Ações de manejo ambiental, educação e promoção à saúde são recomendadas às autoridades municipais para diminuir o risco potencial de infecção na população humana e canina, considerando-se o elevado potencial vetor de Lu. longipalpis e a presença de condições que favorecem a interação dos componentes da tríade epidemiológica da LV.

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The use of planktonic foraminifera in paleoceanographic studies relies on the assumption that morphospecies represent biological species with ecological preferences that are stable through time and space. However, genetic surveys unveiled a considerable level of diversity in most morphospecies of planktonic foraminifera. This diversity is significant for paleoceanographic applications because cryptic species were shown to display distinct ecological preferences that could potentially help refine paleoceanographic proxies. Subtle morphological differences between cryptic species of planktonic foraminifera have been reported, but so far their applicability within paleoceanographic studies remains largely unexplored. Here we show how information on genetic diversity can be transferred to paleoceanography using Globorotalia inflata as a case study. The two cryptic species of G. inflata are separated by the Brazil-Malvinas Confluence (BMC), a major oceanographic feature in the South Atlantic. Based on this observation, we developed a morphological model of cryptic species detection in core top material. The application of the cryptic species detection model to Holocene samples implies latitudinal oscillations in the position of the confluence that are largely consistent with reconstructions obtained from stable isotope data. We show that the occurrence of cryptic species in G. inflata, can be detected in the fossil record and used to trace the migration of the BMC. Since a similar degree of morphological separation as in G. inflata has been reported from other species of planktonic foraminifera, the approach presented in this study can potentially yield a wealth of new paleoceanographical proxies.

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The description of all the species present in nature is a vast task to be fulfilled by using the classical approach of morphological description of the organisms. In recent years, the traditional taxonomy, based primarily on identification keys of species, has shown a number of limitations in the use of the distinctive features in many animal taxa and inconsistencies with the genetic data. Furthermore, the increasing need to get a true estimate of biodiversity has led Zoological Taxonomy to seek new approaches and methodologies to support the traditional methods. The classification procedure has added modern criteriasuch as the evolutionary relationships and the genetic, biochemical and morphological characteristics of the organisms.Until now the Linnean binomial was the only abbreviated code associated with the description of the morphology of a species. The new technologies aim to achieve a short nucleotide sequence of the DNA to be used as an unique and solely label for a particular species, a specific genetic barcode. For both morphological and genetic approaches, skills and experience are required. Taxonomy is one of zoological disciplines that has been benefited from the achievements reached by modern molecular biotechnology. Using a molecular approach it is possible to identify cryptic species, to establish a family relationship between species and their membership of taxonomic categories or to reconstruct the evolutionary history of a taxon.

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Although the value of primary forests for biodiversity conservation is well known, the potential biodiversity and conservation value of regenerating forests remains controversial. Many factors likely contribute to this, including: 1. the variable ages of regenerating forests being studied (often dominated by relatively young regenerating forests); 2. the potential for confounding on-going human disturbance (such as logging and hunting); 3. the relatively low number of multi-taxa studies; 4. the lack of studies that directly compare different historic disturbances within the same location; 5. contrasting patterns from different survey methodologies and the paucity of knowledge on the impacts across different vertical levels of rainforest biodiversity (often due to a lack of suitable methodologies available to assess them). We also know relatively little as to how biodiversity is affected by major current impacts, such as unmarked rainforest roads, which contribute to this degradation of habitat and fragmentation. This thesis explores the potential biodiversity value of regenerating rainforests under the best of scenarios and seeks to understand more about the impact of current human disturbance to biodiversity; data comes from case studies from the Manu and Sumaco Biosphere Reserves in the Western Amazon. Specifically, I compare overall biodiversity and conservation value of a best case regenerating rainforest site with a selection of well-studied primary forest sites and with predicted species lists for the region; including a focus on species of key conservation concern. I then investigate the biodiversity of the same study site in reference to different types of historic anthropogenic disturbance. Following this I investigate the impacts to biodiversity from an unmarked rainforest road. In order to understand more about the differential effects of habitat disturbance on arboreal diversity I directly assess how patterns of butterfly biodiversity vary between three vertical strata. Although assessments within the canopy have been made for birds, invertebrates and bats, very few studies have successfully targeted arboreal mammals. I therefore investigate the potential of camera traps for inventorying arboreal mammal species in comparison with traditional methodologies. Finally, in order to investigate the possibility that different survey methodologies might identify different biodiversity patterns in habitat disturbance assessments, I investigate whether two different but commonly used survey methodologies used to assess amphibians, indicate the same or different responses of amphibian biodiversity to historic habitat change by people. The regenerating rainforest study site contained high levels of species richness; both in terms of alpha diversity found in nearby primary forest areas (87% ±3.5) and in terms of predicted primary forest diversity from the region (83% ±6.7). This included 89% (39 out of 44) of the species of high conservation concern predicted for the Manu region. Faunal species richness in once completely cleared regenerating forest was on average 13% (±9.8) lower than historically selectively logged forest. The presence of the small unmarked road significantly altered levels of faunal biodiversity for three taxa, up to and potentially beyond 350m into the forest interior. Most notably, the impact on biodiversity extended to at least 32% of the whole reserve area. The assessment of butterflies across strata showed that different vertical zones within the same rainforest responded differently in areas with different historic human disturbance. A comparison between forest regenerating after selective logging and forest regenerating after complete clearance, showed that there was a 17% greater reduction in canopy species richness in the historically cleared forest compared with the terrestrial community. Comparing arboreal camera traps with traditional ground-based techniques suggests that camera traps are an effective tool for inventorying secretive arboreal rainforest mammal communities and detect a higher number of cryptic species. Finally, the two survey methodologies used to assess amphibian communities identified contrasting biodiversity patterns in a human modified rainforest; one indicated biodiversity differences between forests with different human disturbance histories, whereas the other suggested no differences between forest disturbance types. Overall, in this thesis I find that the conservation and biodiversity value of regenerating and human disturbed tropical forest can potentially contribute to rainforest biodiversity conservation, particularly in the best of circumstances. I also highlight the importance of utilising appropriate study methodologies that to investigate these three-dimensional habitats, and contribute to the development of methodologies to do so. However, care should be taken when using different survey methodologies, which can provide contrasting biodiversity patterns in response to human disturbance.

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Assessing patterns of connectivity at the community and population levels is relevant to marine resource management and conservation. The present study reviews this issue with a focus on the western Indian Ocean (WIO) biogeographic province. This part of the Indian Ocean holds more species than expected from current models of global reef fish species richness. In this study, checklists of reef fish species were examined to determine levels of endemism in each of 10 biogeographic provinces of the Indian Ocean. Results showed that the number of endemic species was higher in the WIO than in any other region of the Indian Ocean. Endemic species from the WIO on the average had a larger body size than elsewhere in the tropical Indian Ocean. This suggests an effect of peripheral speciation, as previously documented in the Hawaiian reef fish fauna, relative to other sites in the tropical western Pacific. To explore evolutionary dynamics of species across biogeographic provinces and infer mechanisms of speciation, we present and compare the results of phylogeographic surveys based on compilations of published and unpublished mitochondrial DNA sequences for 19 Indo-Pacific reef-associated fishes (rainbow grouper Cephalopholis argus, scrawled butterflyfish Chaetodon meyeri, bluespot mullet Crenimugil sp. A, humbug damselfish Dascyllus abudafur/Dascyllus aruanus, areolate grouper Epinephelus areolatus, blacktip grouper Epinephelus fasciatus, honeycomb grouper Epinephelus merra, bluespotted cornetfish Fistularia commersonii, cleaner wrasse Labroides sp. 1, longface emperor Lethrinus sp. A, bluestripe snapper Lutjanus kasmira, unicornfishes Naso brevirosris, Naso unicornis and Naso vlamingii, blue-spotted maskray Neotrygon kuhlii, largescale mullet Planiliza macrolepis, common parrotfish Scarus psicattus, crescent grunter Terapon jarbua, whitetip reef shark Triaenodon obesus) and three coastal Indo-West Pacific invertebrates (blue seastar Linckia laevigata, spiny lobster Panulirus homarus, small giant clam Tridacna maxima). Heterogeneous and often unbalanced sampling design, paucity of data in a number of cases, and among-species discrepancy in phylogeographic structure precluded any generalization regarding phylogeographic patterns. Nevertheless, the WIO might have been a source of haplotypes in some cases and it also harboured an endemic clade in at least one case. The present survey also highlighted likely cryptic species. This may eventually affect the accuracy of the current checklists of species, which form the basis of some of the recent advances in Indo-West Pacific marine ecology and biogeography.

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Actinia equina, the beadlet sea anemone, is a very labile species, displaying variable colour patterns, broad habitat choice and diverse modes of reproduction. Historically, studies using genetic markers such as allozymes and differences in habitat choice lead several authors to propose that different colour morphs could represent different species. One of the species defined was A. fragacea. In this paper, the relationships between brown, red and green colour morphs of A. equina and A. fragacea were studied, using two DNA fragments (one mitochondrial and one nuclear). Individuals were sampled from three different areas in Portugal separated by a maximum distance of 500 km. This is the first study applying direct sequencing of selected gene fragments to approach the validity of Actinia morphs as different genetic entities. The results show that, at least in the Portuguese coast, these colour morphs do not correspond to the two valid species recognized in the literature. The existence of cryptic species is discussed.

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In this thesis the mostly unknown herpetofauna in Hin Nam No National Protected Area Laos in the northern Truong Son Range was for the first time intensively investigated, and its diversity was compared to the bordering, and well-investigated Phong Nha - Ke Bang National Park in Vietnam. Twelve new vertebrate species were described comprising 11 geckonids (Cyrtodactylus bansocensis, C. calamei, C. hinnamnoensis, C. jaegeri, C. rufford, C. sommerladi, C. soudthichaki, Gekko boehmei, G. bonkowskii, G. sengchanthavongi, G. thakhekensis, Lycodon banksi and one colubrid snake (Lycodon banksi). Seven species were discovered for the first time in Laos including three frogs (Gracixalus quyeti, G. supercornutus, Rhacophorus maximus), two geckos (Cyrtodactylus cryptus, C. pseudoquadrivirgatus) and two snakes (Lycodon futsingensis, L. ruhstrati abditus). The main hypothesis that the Truong Son Range acted as a biogeographic barrier for the distribution of amphibians and reptiles could be confirmed at least for karst adapted gekkonids. Compared to other herpetofaunal groups the number of gekkonids in karst formations was particularly high (seven bent-toed geckos, four true geckos). By comparing the relative amounts of shared species in Hin Nam No and Phong Nha - Ke Bang, it is interesting to note that fewer reptile species (38%) than amphibian species (66%) were shared between both regions. This might indicate that the Truong Son Range acts as a stronger biogeographical barrier for reptiles than for amphibians. Two pairs of karst-adapted cryptic gecko species (i.e. species with distinct genetic differences, but a similar phenotype) occurred on both sides of the Truong Son Range. Only in one case these were sibling species (Crytodactylus sommerladi in Laos versus C. roesleri in Vietnam), but not in the other (C. hinnamnoensis in Laos versus C. phongnhakebangensis in Vietnam). On the Laotian side, nine gecko species (Cyrtodactylus bansocensis, C. calamei, C. darevskii, C. hinnamnoensis, C. khammouanensis, C. multiporus, C. sommerladi, G. boehmei, G. sengchanthavongi) currently have to be regarded as endemic to the Hin Nam No region. On the Vietnamese side, seven species including two bent-toed geckos (Cyrtodactylus phongnhakebangensis and C. roesleri), three skinks (Lygosoma boehmei, Sphenomorphus tetradactylus and Tropidophorus noggei), and two snakes (Hebius andreae and Boiga bourreti) are currently only known from Phong Nha - Ke Bang and adjacent regions. These high numbers of potential endemic species together with the cryptic species complex in Cyrtodactylus provide strong evidence that the karst formations in the northern Truong Son Range represent a hot spot of reptile diversity and of speciation in Crytodactylus in particular. Correct species identification is a fundamental requirement for conservation measures. The discovery of cryptic species complexes poses a challenge for alpha taxonomy and species conservation, because the true distribution ranges of the species are in fact much smaller than previously assumed. Species conservation in this area of Laos is facing a number of further problems. New and potentially endemic species were discovered in highly populated and disturbed areas. Conversion of the Ho Chi Minh Trail into a highway provided easy access for farmers and still continues to accelerate the destruction of remote forest areas. Southern Hin Nam No with its high diversity of endemic species was identified as the first priority area for conservation. Also Ban Soc, an area isolated from Hin Nam No, should be among the conservation priorities because this region houses a so far overlooked population of the critically endangered Siamese crocodile. Efforts to establish a legal conservation status for this habitat are in progress.