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Salvador Carranza and Oscar Arribas

Abstract

The genetic variability of the Pyrenean frog Rana pyrenaica was assessed using DNA sequences of the cytochrome b, COI and 12S rRNA mitochondrial genes. The results show that, despite inhabiting an area of mountainous terrain with high mountain peaks and deep isolated valleys, R. pyrenaica is genetically very homogeneous. The extremely low level of genetic variability observed, even in the fast evolving cytochrome b and COI genes, suggests that R. pyrenaica may have colonized most of its present range very rapidly after the last Würm glaciation from a refuge area in the Prepyrenees. This is the first attempt to establish the level of genetic variability of this endangered Pyrenean endemism and, as a result, it has major implications for its conservation.

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Michael Robinson, Nicholas Arnold and Salvador Carranza

Abstract

Phylogenetic analysis of 1117 bp of mitochondrial DNA sequences (731 bp of cytochrome b and 386 bp of 16S rRNA) indicate that Echis consists of four main clades: E. ocellatus, and the E. coloratus, E. pyramidum, and E. carinatus groups. In the E. coloratus group, E. coloratus itself shows substantial genetic divergence from E. omanensis, corroborating their separate species status. In the E. pyramidum clade, E. pyramidum from Egypt and E. leucogaster from West Africa are genetically very similar, even though samples are separated by 4000 km. South Arabian populations of the E. pyramidum group are much better differentiated from these and two species may be present, animals from Dhofar, southern Oman probably being referable to E. khosatzkii. In the E. carinatus group, specimens of E. carinatus sochureki and E. multisquamatus are very similar in their DNA. The phylogeny indicates that the split between the main groups of Echis was followed by separation of African and Arabian members of the E. pyramidum group, and of E. coloratus and E. omanensis. The last disjunction probably took place at the lowlands that run southwest of the North Oman mountains, which are likely to have been intermittently covered by marine incursions; they also separate the E. pyramidum and E. carinatus groups and several sister taxa of other reptiles. The E. carinatus group may have spread quite recently from North Oman into its very extensive southwest Asian range, and there appears to have been similar expansion of E. pyramidum (including E. leucogaster) in North Africa. Both these events are likely to be associated with the marked climatic changes of the Pleistocene or late Pliocene. Similar dramatic expansions have also recently occurred in three snake species in Iberia.

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Tonnie Woeltjes, Sergé Bogaerts, Salvador Carranza and Frank Pasmans

Abstract

Five new locations of N. strauchii are reported from Turkey, closing the gap between the two subspecies N. s. barani and N. s. strauchii. A molecular analysis based on 829 base pairs from two mitochondrial ribosomal genes (12S and 16S rRNA), together with geographical data from the area concerned, indicate all new populations found are very closely related to the mitochondrial sequences from specimens of N. s. strauchii from its type locality and suggest the river Euphrates might have acted as a natural barrier separating the only populations of N. s. barani known to date from all other populations of N. s. strauchii. A morphological analysis of all N. strauchii populations sampled for this study indicates that belly patterns are not a good diagnostic character to differentiate between N. s. barani and N. s. strauchii, suggesting the only reliable morphological taxonomic character that allows their identification is the different number of yellow spots in adult specimens, which is significantly higher in N. s. strauchii. The analyses also indicate that the number of spots is similar between sub-adult and adult N. s. barani but significantly different between sub-adult and adult specimens of N. s. strauchii, suggesting there is also a difference between both subspecies in increase in the number of spots during maturation.Listed by IUCN as vulnerable and protected by the Bern Convention (1979), our findings indicate N. s. strauchii is more widely distributed than previously thought, while N. s. barani would be restricted to just a few localities. Disturbance of its prime habitat, mountain brooks, and uncontrolled illegal collection, especially of N. s. barani, are still the main threats to the Anatolia newt throughout its known distribution range.

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Neus Oromi, Fèlix Amat, Delfi Sanuy and Salvador Carranza

The Pyrenean brook newt (Calotriton asper) is a salamandrid that mostly lives in fast running and cold mountain-streams, although some populations are also found in lakes. In the present work, we report in detail on the occurrence of facultative paedomorphosis traits in a population from a Pyrenean high altitude lake. We compare its morphology, life history traits and mitochondrial DNA variation with a nearby lotic metamorphic population. Our results indicate that the lacustrine newts are smaller and present a less developed sexual dimorphism, smooth skin, and that 53% of the adults retain gills at different degrees of development, but not gill slits. Although both populations and sexes have the same age at sexual maturity (four years), the lacustrine population presents higher longevity (12 and 9 years for males and females, respectively) than the one living in the stream (8 and 9 years). The variation on the climatic conditions at altitudinal scale is probably the main cause of the differences in life history traits found between the two populations. The food availability, which could to be limiting in the lacustrine population, is another factor that can potentially affect body size. These results are congruent with the significant mitochondrial DNA genetic isolation between populations, probably a consequence of the lack of juvenile dispersal. We found low cytochrome b variability and significant genetic structuring in the lake population that is very remarkably considering the short distance to the nearby stream population and the whole species’ pattern. We suggest that a bottleneck effect and/or phenotypic plasticity may have resulted in the appearance of a paedomorphic morph in the lake.

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Fèlix Amat, Neus Oromí, Delfí Sanuy and Salvador Carranza

Patterns of sexual dimorphism and age structure were investigated in two populations of the newt Calotriton arnoldi, endemic of the Montseny Massif (NE of the Iberian Peninsula). In contrast to the Pyrenean newt (Calotriton asper) sexual dimorphism in the Montseny brook newt is characterized by slightly larger females (60.3 ± 0.3 mm; maximum: 68 mm) than males (59.5 ± 0.2 mm; maximum: 64 mm) and more similar body shape between sexes. Both populations and sexes mature at the same age (3 years), show the same age structure and achieve similar longevity (8-9 years). Comparing our results with the framework of the variation of life-history traits in Calotriton, the Montseny newts exhibit fast sexual maturity and short longevity. Curiously, we have found a lack of covariation between age at sexual maturity, longevity and total body size in the populations of Calotriton species. Only in males, age at sexual maturity seems to be affected by altitude, but in an unexpected way: sexual maturation is delayed in populations at low altitudes. Moreover, the age at sexual maturity does not differs between the populations where immatures are terrestrial vs. those where they remain aquatic. Our results suggest that life-history traits in Calotriton newts could be determined by selective factors that play their role at small geographic scale.

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Salvador Carranza, Alfredo Salvador, Joaquín Verdú-Ricoy, José Díaz and Stephen Busack

Abstract

Relationships among Psammodromus algirus populations from the Iberian Peninsula and North Africa, including recently described P. jeanneae and P. manuelae, were estimated from mitochondrial DNA gene sequences. This enlarged data set confirmed the presence of two divergent eastern and western mitochondrial DNA lineages on the Iberian Peninsula, the distributions for which are separated by a narrow zone of contact across the centre of the Peninsula. Paratypes of P. jeanneae and topotypes of P. manuelae represent southern and northern clades of the western lineage, respectively, making P. algirus paraphyletic. This, together with the low level of allozymic and mitochondrial DNA substructuring within western populations, is not sufficient to retain P. jeanneae and P. manuelae as valid species, and we relegate them to the status of junior synonyms of P. algirus.

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E. Nicholas Arnold, Omar Attum, Bruce Kingsbury, Sherif Baha El Din, Salvador Carranza and Ryan Earley

Abstract

The Egyptian tortoise Testudo kleinmanni was recently split into two species on the basis of apparent differences in shell morphology and markings. Testudo kleinmanni was restricted to areas west of the Nile river and a new form, T. werneri, was described which occurred east of the Nile river (Perälä, 2001). However, when the morphometric analysis on which this decision was based (Perälä, 2001) was adjusted to allow for experiment-wise Type I error, by using P-value corrections, the proportion of the 46 characters that differed significantly between the two populations fell from 36.9% to only 13% in males and from 39.1% to just 8.7% in females. We then conducted a new morphometric analysis using our own data set that showed minor significant variation in morphometric and plastron markings between populations. An analysis of mitochondrial DNA based on 393 base pairs of the 12S rRNA gene, also showed near uniformity of western and eastern populations. Genetic divergence was only 0.2%, with the only consistent difference being a single G – A substitution at position 205. Based on the revised interpretation of Perälä (2001) results, our morphometric analysis on our own data set, and the molecular evidence, the variation observed between populations is normal within a species and therefore T. werneri is not a distinct independent evolutionary lineage and should not be considered a separate species from T. kleinmanni.

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Juan M. Pleguezuelos, Elisa Mora, Philip de Pous, Daniel Escoriza, Margarita Metallinou, David Donaire, Mar Comas and Salvador Carranza

Abstract

The genetic variability and the potential distribution under past (Last Glacial Maximum; LGM (MIROC and CCSM simulations)) and present conditions were studied for the anguid Hyalosaurus koellikeri, using analyses of two mitochondrial (ND1 and ND2) and one nuclear (PRLR) gene and species distribution modelling (SDM) including 19 geographical coordinates, covering most of its distribution range. Unexpectedly, the genetic results show that H. koellikeri presents a very low level of variability both in the mitochondrial and nuclear genes studied. The present predicted distribution of H. koellikeri revealed a large potential distribution in both north and eastwards directions, with suitable areas predicted in places where the species has never been reported before, as for instance the Rif Mountains in Morocco, as well as into most parts of northern Algeria and Tunisia. The LGM distribution is even larger compared to the present, with a continuous predicted distribution from Morocco to Tunisia, and even into Libya under the MIROC simulation. The results of the genetic and SDM analyses suggest that the now isolated populations from Debdou and Tlemcen have probably been in contact during the LGM, but its absence from both present and past predicted suitable areas is still a mystery. Hyalosaurus koellikeri depends mainly on closed deciduous forests (typically Cedrus atlantica and Quercus sp.) and open deciduous shrubland with high amounts of annual rainfall. The results of this study and the absence of recent sightings of the species outside the core distribution might indicate a regression of the species. Hence, a reevaluation of the conservation status of the species seems warranted.

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Miguel Vences, Philip de Pous, Violaine Nicolas, Jesús Díaz-Rodríguez, David Donaire, Karen Hugemann, J. Susanne Hauswaldt, Felix Amat, Juan A.M. Barnestein, Sergé Bogaerts, Abdellah Bouazza, Salvador Carranza, Pedro Galán, Juan Pablo González de la Vega, Ulrich Joger, Aziza Lansari, El Hassan El Mouden, Annemarie Ohler, Delfi Sanuy, Tahar Slimani and Miguel Tejedo

Painted frogs (Discoglossus) contain five to six species of Western Palearctic anurans that are mainly distributed in allopatry. We here provide the first comprehensive assessment of the phylogeography of the Moroccan species D. scovazzi and geographically characterize its contact zone with D. pictus in Eastern Morocco. Discoglossus scovazzi shows, in general, a weak phylogeographic structure across Morocco on the basis of mitochondrial DNA sequences of the cytochrome b gene, with only populations centered in the Atlas Mountains characterized by the presence of slightly divergent haplotypes. In eastern Morocco, all populations east of the Moulouya River were clearly assignable to D. pictus. This species was also found along the Mediterranean coast west of the Moulouya, in the cities of Nador and Melilla, suggesting that not the river itself but the wide arid valley extending along much of the river (except close to the estuary) acts as a possible distributional barrier to these frogs. No sympatry of D. scovazzi with D. pictus was observed, and all specimens were concordantly assigned to either species by DNA sequences of cytochrome b and of the nuclear marker RAG1. Species distribution models of the two taxa show largely overlapping areas of suitable habitat, and the two species’ niches are significantly more similar than would be expected given the underlying environmental differences between the regions in which they occur. Comparative data are also presented from the southern Iberian contact zone of D. galganoi galganoi and D. g. jeanneae. These taxa showed less clear-cut distributional borders, extensively shared RAG1 haplotypes, and had instances of sympatric occurrence on the basis of cytochrome b haplotypes, in agreement with the hypothesis of a yet incomplete speciation. In this wide contact zone area we found mitochondrial sequences containing double peaks in electropherograms, suggesting nuclear pseudogenes or (less likely) heteroplasmy, possibly related to the ongoing admixture among the lineages.