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  • Author or Editor: Daniele Salvi x
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The genus Quedenfeldtia is composed of two species, Q. moerens and Q. trachyblepharus, both endemic to the Atlas Mountains region of Morocco. Previous studies recovered two main genetic lineages within each Quedenfeldtia species, although sampling did not cover a substantial portion of their known distribution. In this study we collected individuals from previously unsampled localities of Quedenfeldtia and carried out genetic analyses in order to assess the range of previously identified lineages and the occurrence of additional lineages. Phylogenetic reconstruction based on both mitochondrial (12S and ND4 + tRNA) and nuclear (MC1R) markers revealed that while the new individuals of Q. moerens belong to previously described lineages, two new lineages of Q. trachyblepharus were uncovered from the northern and southern parts of the range. Genetic divergence of these new lineages (8-9% ND4 + tRNA p-distance) was higher than values observed between other lizard sister species. In the future a thorough morphological assessment is needed to complement this study and allow a taxonomic revision of these taxa. The results of this study highlight the importance of biodiversity assessments in mountainous regions characterized by high endemicity but which are difficult to access.

In: Amphibia-Reptilia

Abstract

Studies of the ecological characteristics of sympatric species are important for developing and testing ecological theory, but may be of interest also for conservation biology research when the study species are threatened, endemic and with narrow distribution. Here, we studied a particular aspect of the ecology (i.e. microhabitat use) of two sympatric lizards (Archaeolacerta bedriagae, Podarcis tiliguerta) endemic to Sardinia and Corsica (Tyrrhenian islands). We studied this issue by modelling procedures, using field data collected at six study areas in both Sardinia and Corsica. We recorded 18 microhabitat variables for each lizard spot. The variables were entered as independent variables in logistic regression analysis with the presence/absence data for the lizards as the dependent variable, and Akaike Information Criterion was applied to select the best models describing the ecological equation of each study species. In total, we based our modelling approach on 296 individuals of A. bedriagae and 182 of P. tiliguerta. The general logistic regression models revealed that five distinct variables were significantly correlated to the presence/absence of A. bedriagae, and six to that of P. tiliguerta. We found that three variables were important for only P. tiliguerta, two for only A. bedriagae, and three for both species and with an identical sign. We also found some similarities in microhabitat choice between species. Indeed, some variables were always present in the best models of both A. bedriagae and P. tiliguerta. In general, A. bedriagae was more related to spots with large stones and low vegetation than P. tiliguerta, which, on the contrary, choose spots relatively closer to vegetation. The various reasons explaining the observed similarities and differences between species were examined. It is suggested that our modelling procedure may be widely used for studies of lizard community ecology, because it easy to use and allows a more-in-depth analysis than normal 'count approaches'.

In: Animal Biology

Abstract

Algyroides fitzingeri is a Corso-Sardinian endemic lizard belonging to a relictual genus within the Lacertini radiation. In recent phylogeographic studies of Corso-Sardinian endemic lizards incongruent patterns are emerging. We investigated the mitochondrial genetic variation of A. fitzingeri across Corsica and Sardinia to obtain a preliminary portrait of its phylogeographic history. This species showed some polymorphism, but with low genetic differentiation between populations, that probably originated during the Pleistocene. Corsican populations are closely related to those from North Sardinia and are likely to have originated from them, given the higher diversity and deeper phylogeographic structure observed in Sardinia than in Corsica. While the phylogeographic structure of A. fitzingeri in Corsica is surprisingly shallow when compared with other co-distributed lizards, in Sardinia a common pattern apparently emerges. Further research is needed to confirm the hypotheses here presented and to provide a conclusive assessment of the phylogeography of this species.

In: Amphibia-Reptilia

Abstract

Many techniques for predicting species potential distribution were recently developed. Despite the international interest for these procedures, applications of predictive approaches to the study of Italian fauna distribution are exceptionally rare. This paper aimed at: (a) detecting climatic exigencies of A. bedriagae in Sardinia; (b) predicting the Archaeolacerta bedriagae Sardinian potential distribution; (c) identifying the most vulnerable Italian populations of the species. Literature and field data were utilized as presence records. Six modelling procedures (BIOCLIM, DOMAIN, ENFA, GAM, GLM, and MAXENT) were adopted. The species climatic requirements were defined using the WorldClim databank for deriving the environmental predictors. AUC and Kappa values were calculated for models validation. AUC values were compared by using Anova Monte Carlo. The best four models were combined through the weighted average consensus method for producing a univocal output. GAM and MAXENT had the best performances (respectively: AUC = 0.93 ± 0.03, Kappa = 0.77 ± 0.08; AUC = 0.93 ± 0.03, Kappa = 0.78 ± 0.07). Good results were also obtained by GLM and DOMAIN (respectively: AUC = 0.89 ± 0.04, Kappa = 0.72 ± 0.05; AUC = 0.88 ± 0.04, Kappa = 0.69 ± 0.07). BIOCLIM and ENFA gained relatively low performances (respectively: AUC = 0.78 ± 0.07, Kappa = 0.57 ± 0.14; AUC = 0.75 ± 0.06; Kappa = 0.49 ± 0.10). In Sardinia A. bedriagae is mainly influenced by seasonality, which causes the evidenced range fragmentation. Moreover, the general importance of multi-methods approaches and consensus techniques in predicting species distribution was highlighted.

In: Amphibia-Reptilia

Abstract

Archaeolacerta bedriagae is a rock lizard endemic to Corsica and Sardinia. Four subspecies have been recozied to date on the basis of morphological traits. Previous allozyme investigations revealed high genetic differentiation among populations of the species. Based on these results some authors hypothesized that more than one species of Archaeolacerta may occur on Corsica and Sardinia. In this paper we investigated allozyme variation at 19 gene loci in 5 populations belonging to all subspecies of A. bedriagae in order to study genetic differentiation among populations from Corsica and Sardinia, and to compare our results with those obtained in previous studies carried out on allozyme variation and taxonomy of the species. Low levels of genetic differentiation (average Nei's D = 0.026) and heterogeneity (mean FST = 0.147) were found comparing the A. bedriagae populations, and there was no evidence of interruption or restriction of gene flow. This is in agreement with the available molecular and morphometric data, while it is not in accordance with allozyme data reported in the previous studies. Our data do not support the hypothesis of an unrecognized criptic species of Archaeolacerta in Corsica and Sardinia, and indicate that the definitive assessment of the taxonomic status of the A. bedriagae populations requires further investigation.

In: Amphibia-Reptilia

Abstract

Identification of extremely high levels of mitochondrial DNA (mtDNA) sequence divergence within reptiles from North Africa is commonplace. This high divergence often compares with interspecific levels among widely accepted species, leading to the hypothesis of the occurrence of species complexes. Indeed, in many examples, data from nuclear markers support such taxonomic recognition. Such is the case of two recently recognized ocellated lizard species of the genus Timon, T. nevadensis, from Spain, and T. kurdistanicus, from the Middle East, which both showed notable genetic differentiation from their sister taxa. In North Africa, highly divergent mtDNA lineages of Timon tangitanus were previously identified but not corroborated with nuclear markers. Here we expand geographic sampling across the range of Timon tangitanus and complement mtDNA sequences with data from nuclear markers (MC1R and ACM4). We identify four divergent mtDNA lineages, at a level similar to some reptile species. However, the nuclear markers show limited differentiation and lack of lineage sorting. This and some other recent assessments within reptiles discourage the use of mtDNA data alone as a proxy for taxonomic units, demonstrating once more the need for integrative taxonomic approaches.

In: Amphibia-Reptilia

Abstract

The common wall lizard has been widely introduced across Europe and overseas. We investigated the origin of putatively introduced Podarcis muralis populations from two southern Europe localities: (i) Ljubljana (Slovenia), where uncommon phenotypes were observed near the railway tracks and (ii) the port of Vigo (Spain), where the species was recently found 150 km far from its previously known range. We compared cytochrome-b mtDNA sequences of lizards from these populations with published sequences across the native range. Our results support the allochthonous status and multiple, long-distance origins in both populations. In Ljubljana, results support two different origins, Serbia and Italy. In Vigo, at least two separate origins are inferred, from western and eastern France. Such results confirm that human-mediated transport is promoting biological invasion and lineage admixture in this species. Solid knowledge of the origin and invasion pathways, as well as population monitoring, is crucial for management strategies to be successful.

In: Amphibia-Reptilia

Abstract

The ‘smooth newt’, the taxon traditionally referred to as Lissotriton vulgaris, consists of multiple morphologically distinct taxa. Given the uncertainty concerning the validity and rank of these taxa, L. vulgaris sensu lato has often been treated as a single, polytypic species. A recent study, driven by genetic data, proposed to recognize five species, L. graecus, L. kosswigi, L. lantzi, L. schmidtleri and a more restricted L. vulgaris. The Carpathian newt L. montandoni was confirmed to be a closely related sister species. We propose to refer to this collective of six Lissotriton species as the smooth newt or Lissotriton vulgaris species complex. Guided by comprehensive genomic data from throughout the range of the smooth newt species complex we 1) delineate the distribution ranges, 2) provide a distribution database, and 3) produce distribution maps according to the format of the New Atlas of Amphibians and Reptiles of Europe, for the six constituent species. This allows us to 4) highlight regions where more research is needed to determine the position of contact zones.

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In: Amphibia-Reptilia