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Die Beziehungen der beiden rezenten kanarischen Rieseneidechsenarten Gallotia simonyi und G. stehlini werden diskutiert. Der Lebensraum und, soweit bekannt, die Lebensweise werden beschrieben. Es folgen einige Bemerkungen über die vom Aussterben bedrohte G. simonyi und abschließend einige Hinweise zur Haltung von G. stehlini im Terrarium.

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Variability of biometric characters and colour patterns was studies in 287 specimens of Gallotia atlantica from all parts of its range. Results indicate a hierarchial system of infraspecific groups. With regard to historical and topographical aspects (isolation time jedged from isobates) two different population groups (Lanzarote and surrounding islets; Fuertenventura and Lobos) are distinguished. They represent two subspecies, Gallotia atlantica atlantica and Gallotia atlantica mahoratae. Furthermore, it is argued that the observed differences in colouration have an adaptive value.

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Das kleine »Galapagos vor der europäischen Haustür« ist Gegenstand dieses in sich geschlossenen Bandes. Er gibt erstmalig einen Überblick über die Herpetofauna dieser Inselgruppen.

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The phylogeography of the lacertid lizard Gallotia atlantica from the small volcanic island of Lanzarote (Canary Islands) was analysed based on 1075 bp of mitochondrial DNA (mtDNA) sequence (partial cytochrome b and ND2) for 157 individuals from 27 sites (including three sites from neighbouring islets). Levels of sequence divergence were generally low, with the most distant haplotypes separated by only 14 mutational steps. MtDNA divergence appears to coincide with formation of the middle Pleistocene lowland that united formerly separate ancient islands to form the current island of Lanzarote, allowing rejection of a two-island model of phylogeographical structure. There was evidence of large-scale population expansion after island unification, consistent with the colonization of new areas. A nested clade phylogeographical analysis (NCPA) revealed significant phylogeographical structuring. Two-step and higher-level clades each had disjunct distributions, being found to the east and west of a common area with a north-south orientation that extends between coasts in the centre-east of the island (El Jable). Other clades were almost entirely restricted to the El Jable region alone. Bayesian Markov chain Monte Carlo analyses were used to separate ongoing gene flow from historical associations. These supported the NCPA by indicating recent (75 000-150 000 years ago) east-west vicariance across the El Jable region. Lava flows covered El Jable and other parts of the central lowland at this time and likely led to population extinctions and temporary dispersal barriers, although present-day evidence suggests some populations would have survived in small refugia. Expansion of the latter appears to explain the presence of a clade located between the eastern and western components of the disjunct clades. Direct relationships between mtDNA lineages and morphology were not found, although one of two morphological forms on the island has a disjunct distribution that is broadly concordant with east-west components of the phylogeographical pattern. This work demonstrates how recent volcanic activity can cause population fragmentation and thus shape genetic diversity on microgeographical scales.

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Phylogenetic relationships among species and subspecies of the Canary Island endemic lizard genus Gallotia are inferred base on nucleotide sequence of fragments of 12S ribosomal RNA and cytochrome b mitochondrial genes. The four morphologically established species have also been recognized at the molecular level. Relative affinities among species follow an eatsern-western geographic transect. The nearly extinct species Galloti simonyi from the most western island of El Hierro is closely related to the common western species Gallotia galloti. The nearest branch to this pair is Gallotia stehlini from the central island of Gran Canaria, and finally, Gallotia atlantica from the two eastern and geologically oldest islands appears as the most distantly related species of the group. At the statistical level, four subspecies can be recognized in G. galloti, but only two in G. atlantica.

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The implementation of molecular tools in parasitology has led to the discovery of numerous cryptic species. However, detailed morphological studies are needed to evaluate the cryptic nature of such species, as well as to provide an appropriate and formal description. Recent phylogenetic analyses using mitochondrial and nuclear genes have revealed that the nematode Spauligodon atlanticus, parasite of lizards of the genus Gallotia endemic to the Canary Islands, consists of two highly divergent and unrelated lineages, one in the eastern islands and the other in the western ones. This study provides a detailed morphological analysis of the two S. atlanticus lineages characterized genetically, based on body measurements and scanning electron microscopy. This integrative approach revealed phenotypic differences between them, despite their overall morphological resemblance. As a result, the new species Spauligodon occidentalis sp. nov., from the formerly western lineage, is described. The morphological similarity between the two Spauligodon species is better explained on the basis of evolutionary convergence, since both species parasitize Gallotia lizards. In addition to delimiting the new nematode species, this study highlights the importance of combining genetic and morphological data with taxonomy to uncover the nature of cryptic species and decrease taxonomic uncertainty.

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Gallotia atlantica is a lizard endemic to the eastermost islands of the Canary Islands. However, there is also one population present on Gran Canaria. Once described as a different subspecies than the ones from Lanzarote and Fuerteventura, it is now acknowledged that this population was introduced on Gran Canaria. According to different publications, this population was attributed either to Gallotia atlantica atlantica or to Gallotia atlantica mahoratae. Here, the author gives the clarification why the population on Gran Canaria should be considered as Gallotia atlantica atlantica and not Gallotia atlantica mahoratae.

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All recent members of the genus Gallotia from the seven large isles of the Canary Archipelago have been investigated immunologically by means of micro-complement- fixation technique. Three species of genera living in NW-Africa were used as outgroup. Prom the evolutionary tree constructed from the results isolation times can be estimated and ways of colonization can be reconstructed. Various possibilities of insertion of the fossil species G . goliath in the evolutionary tree are discussed.

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I examined sexual dimorphism in the lacertids Gallotia atlantica atlantica and Gallotia atlantica mahoratae from Lanzarote and Fuerteventura Islands, respectively. Mean body size was smaller in G. a. mahoratae than in G. a. atlantica. Sexual size dimorphism was greater in G. a. atlantica than in G. a. mahoratae, but relative size of several morphological traits was not different between the two populations. In both subspecies, head and body traits scaled to SVL, with head size of males having a positive allometry, indicating a disproportionate increase of this trait with the increase in body size. Relative size in hind-limb length was greater in males than in females in G. a. atlantica but not in G. a. mahoratae.

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The aim was to study as to how biometric and life-history traits of endemic lacertids in the Canary Islands (genus Gallotia) may have evolved, and possible factors affecting the diversification process of this taxon on successively appearing islands have been deduced. To that end, comparative analyses of sexual dimorphism and scaling of different body, head and life-history traits to body size in 10 species/subspecies of Gallotia have been carried out. Both Felsenstein`s independent contrasts and Huey and Bennett`s `minimum evolution` analyses show that male and female snout-vent length (SVL) changed proportionally (sexual size dimorphism not changing with body size) throughout the evolution of these lizards and all within-sex biometric traits have changed proportionally to SVL. Life-history traits (size at sexual maturity, clutch size, hatchling SVL and mass, and life span) are highly correlated with adult female body size, the first two being the only traits with a positive allometry to female SVL. These results, together with the finding that the slope of hatchling SVL to female SVL regression was lower than that of SVL at maturity to female SVL, indicates that larger females reach maturity at a larger size, have larger clutches and, at the same time, have relatively smaller hatchlings than smaller females. There was no significant correlation between any pair of life-history traits after statistically removing the effect of body size. As most traits changed proportionally to SVL, the major evolutionary change has been that of body size (a ca. threefold change between the largest and the smallest species), that is suggested to be the effect of variable ecological conditions faced by founder lizards in each island.

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I examined sexual dimorphism in the lacertids Gallotia atlantica atlantica and Gallotia atlantica mahoratae from Lanzarote and Fuerteventura Islands, respectively. Mean body size was smaller in G. a. mahoratae than in G. a. atlantica. Sexual size dimorphism was greater in G. a. atlantica than in G. a. mahoratae, but relative size of several morphological traits was not different between the two populations. In both subspecies, head and body traits scaled to SVL, with head size of males having a positive allometry, indicating a disproportionate increase of this trait with the increase in body size. Relative size in hind-limb length was greater in males than in females in G. a. atlantica but not in G. a. mahoratae.

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Die Kanareneidechsen der Gattung Gallotia gehören zu den chasrismatischten Vertretern der Lacertidae. Durch ihr Vorkommen auf den beliebten Urlaubsinseln, ihre Größe und ihr teils massenhaftes Auftreten sind sire auch bei Laien recht bekannt, während die packenden bis dramatischen Geschichten rund um die beinahe ausgestorbenen Rieseneidechsen die Fachleute elektrisieren. Im seltsamen Mißverhältnis dazu steht, dass diese kräftigen, teils farbenfrohen Echsen in der letzten Zeit in der Terraristik nur noch wenig beachtet worden sind. Zeit für eine Ehrenrettung!

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Observation of introduced lizard species on the Canary Islands of Gran Canaria and Fuerteventura. Teira dugesii from Madeira has been observed on Gran Canaria, Gallotia stehlini, originally from Gran Canaria, on the island of Fuerteventura. Also on Fuerteventura, the evidence of Gallotia galloti eisentrauti, introduced from Tenerife, was confirmed.