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Algeria is a case study of biodiversity ignorance. To date, there are neither complete inventories for any taxa nor atlas across the country! Yet, Algeria is of great importance for global biodiversity. The coastal area of Algeria is part of the global biodiversity hostpot which is the Mediterranean perimeter and has several regional red spots of biodiversity. Moreover, the Saharan part encompasses a diversity of endemic organisms adapted to the strong conditions of drought. The Algerian authorities are deploying an ambitious project for conservation aiming to reach 50% of the country`s surface as protected areas! However, the location of these protected areas and their management don’t obey to a scientific evidence based, but are rather based on experts opinion. The main aim of this thesis is the study of the biodiversity ignorance distribution in Algeria by focusing on the `Linnean, Wallacean, and Darwinian Shortfalls` and to contribute to reduce them. The first chapter aims at reducing the Linnean Shortfall by proposing 1) a first checklist of reptiles and amphibians of Algeria which is the result of an accurate review of scientific publications on these taxa in North Africa. 2) a first pre-assessment of the conservation status of reptiles and amphibians of Algeria for the production of the first national red list. The second part of this manuscript deals with the ignorance of the geographical distribution of species. The purpose of this part is to map the ignorance which is defined as the difference between the expected specific richness diversity and the observed specific richness. The predicted species richness was modelled with two approaches: 1 ecological niche modelling with the maximum entropy method (MaxEnt) to predict the suitable habitats for each species and then add the different binary layers of species presence to calculate the specific richness. 2) Minimum convex polygon method was used to create range maps of each species and were auditioned to obtain predicted species richness. Both approaches have shown the same trend at a national scale: the concentration of the richest areas along the Saharan Atlas and the High Plateaus which are the transition zone between the Sahara and the Mediterranean part of Algeria. The opposition of the Saharan with a low species richness and the northern part with a higher species richness. Finally, the Saharan massifs of the Hoggar and Tassili form a very distinct zone with a much greater wealth compared to the rest of the Sahara. In terms of gaps, in the northern part, Kabylie, El Kala National Park and the Oran region are fairly well surveyed. In the Sahara, only a few points are clearly well prospected as Biskra, Bechar and some areas of the Hoggar and Tassili. The third part deals with the distribution of genetic llineages in the Maghreb. The aim of this section is to locate the phylogeographic breaks between the divergent eastern and western populations of the Maghreb and to try to understand the mechanisms that led to this pattern of genetic diversity. To answer these questions, I carried out a comparative phylogeography on 11 species of reptiles and amphibians with continuous and wide distribution in the Maghreb. Two suture zones have been identified: one zone on the border of Algeria and Morocco, the other in Kabylia west of the Soummam valley. The divergences between the eastern clades and the western clades occurred between the pre-Messinian periods up to the pliopleistocene boundary and were maintained in climatic refugia in the East and West of the Maghreb.

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Mitochondrial DNA sequences consisting of 645 sites from the 12S rRNA and 16S rRNA genes were used to estimate the phylogeny of 15 of the 32 species of spiny-footed lizards Acanthodactylus. The resultant tree has similarities to that produced from a differentially weighted data set of 32 morphological characters but there are also significant differences. However, combined analysis of molecular and morphological data sets produces the same tree topology as DNA sequence alone. The molecular data confirm that there are distinct eastern and western clades within Acanthodactylus, but place A. boskianus in the former while the A. scutellatus group constitutes a third clade. Species for which only morphological information is available were integrated with the combined tree to give a provisional phylogeny for 31 species. This phylogeny indicates that the ancestor of existing Acanthodactylus probably originated in south-west Asia and that North Africa was invaded by more than one lineage of the genus. It also suggests that soft aeolian sand habitats may have been independently occupied more than once. Molecular data provide independent evidence that the differential weighting of morphological characters in past analyses was appropriate.

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Aim To map and assess the richness patterns of reptiles (and included groups: amphisbaenians, crocodiles, lizards, snakes and turtles) in Africa, quantify the overlap in species richness of reptiles (and included groups) with the other terrestrial vertebrate classes, investigate the environmental correlates underlying these patterns, and evaluate the role of range size on richness patterns. Location Africa. Methods We assembled a data set of distributions of all African reptile species. We tested the spatial congruence of reptile richness with that of amphibians, birds and mammals. We further tested the relative importance of temperature, precipitation, elevation range and net primary productivity for species richness over two spatial scales (ecoregions and 1° grids). We arranged reptile and vertebrate groups into range-size quartiles in order to evaluate the role of range size in producing richness patterns. Results Reptile, amphibian, bird and mammal richness are largely congruent (r = 0.79–0.86) and respond similarly to environmental variables (mainly productivity and precipitation). Ecoregion size accounts for more variation in the richness of reptiles than in that of other groups. Lizard distributions are distinct with several areas of high species richness where other vertebrate groups (including snakes) are species-poor, especially in arid ecoregions. Habitat heterogeneity is the best predictor of narrow-ranging species, but remains relatively important in explaining lizard richness even for species with large range sizes. Main conclusions Reptile richness varies with similar environmental variables as the other vertebrates in Africa, reflecting the disproportionate influence of snakes on reptile richness, a result of their large ranges. Richness gradients of narrow-ranged vertebrates differ from those of widespread taxa, which may demonstrate different centres of endemism for reptile subclades in Africa. Lizard richness varies mostly with habitat heterogeneity independent of range size, which suggests that the difference in response of lizards is due to their ecological characteristics. These results, over two spatial scales and multiple range-size quartiles, allow us to reliably interpret the influence of environmental variables on patterns of reptile richness and congruency.

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Aim Body size is instrumental in influencing animal physiology, morphology, ecology and evolution, as well as extinction risk. I examine several hypotheses regarding the influence of body size on lizard evolution and extinction risk, assessing whether body size influences, or is influenced by, species richness, herbivory, island dwelling and extinction risk. Location World-wide. Methods I used literature data and measurements of museum and live specimens to estimate lizard body size distributions. Results I obtained body size data for 99% of the world`s lizard species. The body size–frequency distribution is highly modal and right skewed and similar distributions characterize most lizard families and lizard assemblages across biogeographical realms. There is a strong negative correlation between mean body size within families and species richness. Herbivorous lizards are larger than omnivorous and carnivorous ones, and aquatic lizards are larger than non-aquatic species. Diurnal activity is associated with small body size. Insular lizards tend towards both extremes of the size spectrum. Extinction risk increases with body size of species for which risk has been assessed. Main conclusions Small size seems to promote fast diversification of disparate body plans. The absence of mammalian predators allows insular lizards to attain larger body sizes by means of release from predation and allows them to evolve into the top predator niche. Island living also promotes a high frequency of herbivory, which is also associated with large size. Aquatic and nocturnal lizards probably evolve large size because of thermal constraints. The association between large size and high extinction risk, however, probably reflects a bias in the species in which risk has been studied.

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Algeria is situated at the crossroads between Europe and Africa. The northern part of the country is listed as an area of high biodiversity. Currently, the ecosystems (rivers, lakes, deserts, forests etc.) and the species are under more pressure than ever. The impact of humans is significant and many factors constitute a strong threat to this fauna, especially reptiles, which are the most vulnerable because of their low mobility. Thus, pollution, the drying up of wetlands and their conversion to agriculture have clearly affected the existence of many species. The herpetofauna of Algeria is one of the most diversified in the Mediterranean Basin, consisting of 104 species of which 16.98% are endemic. We suppose that the present list of reptilian fauna provided in this paper is not exhaustive and it is expected to include more species given the lack of research on reptiles in Algeria and its large area. Our dataset contains information on reptile occurrences in Algeria. The dataset is based on original research by the staff of the Laboratory of Environmental Sciences and Agroecology of Chadli Bendjedid University in Algeria. The conservation status of all recorded species is given.

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Die vorliegende Revision betrifft die Gattung Acanthodactylus (Damilie Lacertidae), die die Trocken- und Wüstengebiete des nördlichen Afrika und des südwestlichen Asiens bewohnt, mit Randpopulationen auf der Iberischen Halbinsel und auf Zypern. Mehr als 6000 Exemplare der Gattung, aus den bedeutendsten europäischen und amerikanischen Sammlungen, wurden untersucht. Zusätzlich wurden über 450 Röntgenaufnahmen für osteologische Untersuchungen ausgewertet. Die historische Übersicht behandelt in chronologischer Reihenfolge alle Arbeiten, die sich mit der Gattung Acanthodactylus beschäftigen, mit besonderer Berücksichtigung taxonomischer Studien. Ein beigegebener Bestimmungsschlüssel ermöglicht die Determination aller Arten der Gattung. Eine Reihe äußerer (Größe und Proportionen, Pholidose, Färbung und Zeichnung) und innerer (d.h. osteologischer) Merkmale wurde im Hinblick auf ihre Variabilität untersucht. Dann wurde ein Land ausgesucht, z.B. Ägypten, aus dem eine gute Materialbasis zur Verfügung stand. Für einen bestimmten Fundort in diesem Lande wurden sodann einige Kombinationen von Merkmalszuständen ermittelt, die sich aus dem Auftreten verschiedener Arten ergaben. Derselbe Vorgang wurde sodann auf den Rest Ägyptens übertragen, und die Merkmalskombinationen stellten sich als übereinstimmend heraus; sie erlaubten dadurch eine sichere Zuordnung von Tieren zu folgen Arten: A. boskianus, A. scutellatus und A. pardalis. Durch die Ausdehnung der Untersuchung nach Westen und Osten kamen weitere Taxa hinzu. Besonderer Aufmerksamkeit wurde diesen Merkmalskombinationen im Hinblick auf sympatrisches oder allopatrisches Auftreten der betroffenen Arten gezollt, mit dem Ergebnis, daß es in einigen Fällen möglich war, abzusichern, daß es sich um Populationen derselben Art handelt. Die Gattung Acanthodactylus wurde in mehrere Artengruppen gegliedert, die sich durch engere Beziehungen ihrer Arten untereinander auszeichnen. Die erste ist die micropholis-Gruppe mit der einzigen Art A. micropholis. Sie wird als die ursprünglichste der gesamten Gattung angesehen. Eine weitere Gruppe ist die boskianus-Gruppe, mit den Arten A. boskianus und A. schreiberi. Erstere wird ausführlich analysiert im Hinblick auf ihre außerordentlich große geographische Variabilität. Die yemenicus-Gruppe besiedelt die Arabische Halbinsel und besteht aus A. yemenicus sp.n., A. masirae, A. opheodurus und A. felicis. Eine weitere Gruppe ist die tristrami-Gruppe mit den Arten A. tristrami und A. robustus. Für erstere wird die Validität der Unterart orientalis verneint, die für iracensis dagegen bejaht. In die grandis-Gruppe wird hier nur A. grandis gestellt, während A. fraseri als dessen Synonym aufgefaßt wird. Die erythrurus-Gruppe enthält A. erythrurus, A. savignyi, A. blanci, A. boueti und A. guineensis. Letzterer rangierte bislang in der Gattung Eremias, gehört aber nach den hier vorgelegten Befunden in die erythrurus-Gruppe von Acanthodactylus. In der pardalis-Gruppe sind enthalten: A. pardalis, A. bedriagai, A. maculatus, A. spinicauda und A. busacki sp.n. aus Marokko. Die scutellatus-Gruppe besteht aus A. scutellatus, A. aureus, A. dumerili und A. longipes. Die letzte Gruppe ist die cantoris-Gruppe mit den Arten A. cantoris, A. arabicus, A. schmidti, A. blanfordi, A. gongrorhynchatus und A. haasi. Eine Bibliographie über die Gattung beschließt die Arbeit. Für jede Art werden Diagnosen, Verbreitungskarten, Synonymien, Beschreibungen und Materiallisten der untersuchten Tiere sowie auch Strichzeichnungen gegeben.