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Hundsdoerfer A.K.,Museum of Zoology Museum fur Tierkunde | Kitching I.J.,Natural History Museum in London
Arthropod Systematics and Phylogeny | Year: 2010

The external and internal genitalia of Lepidoptera have long provided a wealth of taxonomic and phylogenetic characters. However, traditional genitalia preparation techniques destroy both DNA, which is increasingly being used in Lepidoptera phylogenetics and species discrimination, and the scale pattern of the abdomen. In this paper, we describe a procedure for extracting both DNA for sequence analysis and genitalia from large Lepidoptera while retaining the surface scaling of the abdomen and, by permitting reattachment of the empty but still scaled abdomen, the general appearance of the specimens. Specimens both before and after the procedure has been undertaken are illustrated. © Museum für Tierkunde Dresden. Source


Delfino M.,University of Zurich | Delfino M.,University of Florence | Fritz U.,Museum of Zoology Museum fur Tierkunde | Sanchez-Villagra M.R.,University of Zurich
Organisms Diversity and Evolution | Year: 2010

In order to examine the evolution of the phalangeal formula in a diverse clade of turtles, including hyperphalangy as a rare condition in this group, we studied 210 specimens representing all extant genera of Trionychidae and their sister taxon, Carettochelyidae. Both groups consist of highly aquatic species with elongated autopods that are either paddle-like (Trionychidae) or transformed to flippers (Carettochelyidae). Phalangeal formulae were obtained mostly by radiographs of alcohol-preserved or dry specimens, as well as by direct counts from skeletons. All trionychids and Carettochelys are pentadactylous, but their phalangeal formulae differ. Carettochelys exhibits the turtle-plesiomorphic state (manus and pes: 2-3-3-3-3), with no variation in adults. Trionychids exhibit intraspecific variation, ranging from 2-3-3-3-2 to 2-3-3-6-5 for the manus, and from 2-3-3-3-2 to 2-3-3-5-3 for the pes. The extant Carettochelys as well as the Middle Eocene Allaeochelys crassesculpta are characterized by an elongation of phalanges, whereas trionychids consistently have shorter phalanges. All trionychid genera exhibit some degree of hyperphalangy in digits IV and V, in both the manus and pes. Phalanges of the clawed digits I-III are very robust compared to phalanges of the non-clawed digits IV and V. The latter contribute significantly to the enlargement of the paddle by their additional phalanges. We hypothesize that this phalangeal pattern is coupled with prolongation of growth processes in the non-clawed digits. The differences in autopod morphology between carettochelyids and trionychids reflect different locomotor patterns related to different natural histories (elongated flippers for high-speed escape in the mainly herbivorous Carettochelys; broad paddles for rapid turns during hunting in the mainly carnivorous trionychids). The autopod of Pelodiscus sinensis is proposed as an experimental model to examine the developmental basis of adult autopod variation. Source


Vargas-Ramirez M.,Museum of Zoology Museum fur Tierkunde | Maran J.,LAssociation du Refuge des Tortues | Fritz U.,Museum of Zoology Museum fur Tierkunde
Organisms Diversity and Evolution | Year: 2010

Using sequence data of the mitochondrial cytochrome b gene, we investigated phylogeographic differentiation of the Amazonian tortoise species Chelonoidis carbonaria and C. denticulata. While C. carbonaria is generally restricted to savannah habitats and adjacent forests, C. denticulata is associated with wet tropical and subtropical forests. Our study suggests a correlation between distinct habitat preferences and phylogeography of the two species. In Maximum Parsimony, Maximum Likelihood and Bayesian analyses, haplotypes of C. carbonaria cluster in several distinct clades reflecting the species' patchy distribution in savannah habitats. By contrast, haplotypes of C. denticulata are only weakly differentiated; a finding also confirmed by parsimony network analysis. This suggests that the contiguous Amazonian rainforest allows gene flow between populations of the forest-dwelling C. denticulata throughout the range, but significantly impedes gene flow in C. carbonaria. The phylogeographic structure and extant distribution pattern of C. carbonaria is supportive of former Amazonian rainforest fragmentation, enabling the dispersal of savannah species. Based on fossil calibration, we dated divergence times for the C. carbonaria clades using a relaxed molecular clock, resulting in average estimates ranging from 4.0-2.2 mya. This implies that the onset of rainforest fragmentation could predate the Pleistocene considerably. Furthermore, our findings call for further research on geographic and taxonomie variation in C. carbonaria and for a reassessment of the conservation status of the distinct genetic units. © Gesellschaft für Biologische Systematik 2010. Source


Vamberger M.,Museum of Zoology Museum fur Tierkunde | Corti C.,University of Florence | Stuckas H.,Museum of Zoology Museum fur Tierkunde | Fritz U.,Museum of Zoology Museum fur Tierkunde
Amphibia Reptilia | Year: 2011

Using mtDNA sequences and 12 microsatellite loci, we compare populations of Testudo graeca from Sardinia and North Africa. The observed pattern of almost no differentiation combined with reduced variation in the Sardinian population is consistent with introduction in prehistoric or historic times from what is now Tunisia and neighbouring Algeria. Furthermore, in the light of the recently published recommendation to eradicate the non-native T. graeca from Italy, we review recent studies on the archaeological and fossil record, on the phylogeography and population genetics of the three other chelonian species occurring in Sardinia (Emys orbicularis, T. hermanni, T. marginata). We conclude that the extant Sardinian populations of all four species are not native. However, they are and should be safeguarded under EC law (Council Regulation No 338/97 on the Protection of Species of Wild Fauna and Flora; Flora Fauna Habitat Directive: Appendix IV, Art. 12) because they serve as a back-up for the declining mainland populations. Moreover, these populations constitute an important part of the human-shaped natural heritage of the Mediterranean. © 2011 BRILL. Source


Fritz U.,Museum of Zoology Museum fur Tierkunde | Corti C.,University of Florence | Packert M.,Museum of Zoology Museum fur Tierkunde
Organisms Diversity and Evolution | Year: 2012

We supplement a previously published mitochondrial DNA data set of grass snake sequences (ND1, ND2, ND4, cyt b, in total 3,806 bp) with sequences of Corso-Sardinian and Tuscan specimens and infer their phylogeny using Bayesian, maximum likelihood and maximum parsimony methods. In addition, we estimate divergence times of grass snake clades using a relaxed molecular clock calibrated with fossil evidence, and, in a second approach, the post-Messinian reopening of the Strait of Gibraltar. Recently it was suggested that Corso-Sardinian grass snakes represent a distinct species: Natrix cetti. All tree-building methods revealed well-supported branching patterns and deep divergences among grass snakes. However, sequences of N. natrix were consistently paraphyletic with respect to Corso-Sardinian sequences. The sister group of Corso-Sardinian grass snakes is a clade embracing N. n. helvetica and N. n. lanzai. Extensive gene flow between N. n. helvetica and a more distantly related subspecies (N. n. natrix) is well known, which is why we conclude that the status of Corso-Sardinian grass snakes as subspecies of N. natrix should be reinstated. Many currently recognized grass snake subspecies conflict with mitochondrial clades, suggestive of inappropriate morphological taxon delineation and mitochondrial introgression. Divergences among grass snakes are old, and the results of the two independent dating approaches are largely congruent. Accordingly, the Alpine orogenesis seems to have caused the origin of the oldest clade, corresponding to Iberian N. n. astreptophora. The formation of Corso-Sardinian grass snakes was dated to the Early Pliocene and could result from post-Messinian flooding of the Mediterranean Basin. Another deeply divergent clade of approximately the same age, endemic in central and northern Europe, suggests the Pleistocene survival of grass snakes north of the Alps. At least one glacial refuge in which old lineages survived Pleistocene cold periods was located on each of the three major southern European peninsulas and in Anatolia. Due to pronounced sequence divergences among Italian and southern Swiss grass snakes, we hypothesize multiple refugia south of the Alps and in the Apennine Peninsula, and there is evidence for two refuges on the Balkan Peninsula. © 2012 Gesellschaft für Biologische Systematik. Source

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