Emydidae

Abstract: Ecological diversification is a central topic in ecology and evolutionary biology. We undertook the first comprehensive species-level phylogenetic analysis of Emydidae (an ecologically diverse group of turtles), and used the resulting phy- logeny to test four general hypotheses about ecological diversification. Phylogenetic analyses were based on data from morphology (237 parsimony-informative characters) and mitochondrial DNA sequences (547 parsimony-infor- mative characters) and included 39 of the 40 currently recognized emydid species. Combined analyses of all data pro- vide a well-supported hypothesis for intergeneric relationships, and support monophyly of the two subfamilies (Emydinae and Deirochelyinae) and most genera (with the notable exception of Clemmys and Trachemys ). Habitat and diet were mapped onto the combined-data tree to test fundamental hypotheses about ecological diversification. Using continuous coding of ecological characters showed that lineages changed in habitat before diet, ecological change was most frequently from generalist to specialist, and habitat and diet rarely changed on the same branch of the phylogeny. However, we also demonstrate that the results of ancestral trait reconstructions can be highly sen- sitive to character coding method (i.e. continuous vs. discrete). Finally, we propose a simple model to describe the pat- tern of ecological diversification in emydid turtles and other lineages, which may reconcile the (seemingly) conflicting conclusions of our study and two recent reviews of ecological diversification. © 2003 The Linnean Society of London, Biological Journal of the Linnean Society , 2003, 79 , 577-610.

Abstract: Geographic variation in the mtDNA haplotypes (cytochrome b gene) of 127 European pond turtles from Italy was investigated. Thirty-eight of the Italian samples were also studied by nuclear fingerprinting (ISSR PCR) and compared with samples from other parts of the range representing all nine currently known mtDNA lineages of Emys orbicularis. Our genetic findings were compared against morphological data sets (measurements, colour pattern) for 109 adult turtles from southern Italy. Italy is displaying on a small geographical scale the most complicated variation known over the entire distributional area of Emys (North Africa over Europe and Asia Minor to the Caspian and Aral Seas). The Tyrrhenic coast of the Apennine Peninsula, the Mt. Pollino area and Basilicata are inhabited by Emys orbicularis galloitalica, a subspecies harbouring a distinct mtDNA lineage. The same lineage is also found in Sardinia. Along the Adriatic coast of Italy and on the Salentine Peninsula (Apulia, southern Italy), another morphologically distinctive subspecies (Emys orbicularis hellenica) occurs, which also bears a different mtDNA lineage. A higher diversity of mtDNA haplotypes in the south of the Apennine Peninsula suggests that the glacial refugia of E. o. galloitalica and E. o. hellenica were located here. A further refuge of E. o. hellenica probably existed in the southern Balkans. The west coasts of the Balkans and Corfu have probably been colonized from Italy and not from the geographically closer southern Balkanic refuge. In Sicily, a third mtDNA lineage is distributed, which is sister to all other known lineages of Emys. Morphologically, Sicilian pond turtles resemble E. o. galloitalica. However, nuclear fingerprinting revealed a clear distinctiveness of the Sicilian taxon, whereas no significant divergence was detected between representatives of the other eight mtDNA lineages of Emys. Furthermore, nuclear fingerprinting provided no evidence for current or past gene flow between the Sicilian taxon and the mainland subspecies of E. orbicularis. Therefore, Sicilian pond turtles are described here as a species new to science. Some populations in Calabria and on the Salentine Peninsula comprise individuals of different mtDNA lineages. We interpret this as a natural contact. However, we cannot exclude that these syntopic occurrences are the result of human activity. For example, in other parts of Italy, the natural distribution pattern of Emys is obscured by allochthonous turtles. This could also be true for southern Italy. The discovery of the complex taxonomic differentiation in southern Italy requires reconsidering conservation strategies.

Abstract: G-, C-, Q-banding and standard karyotypic analyses were used to study the chromosomal relationships of emydid turtles. Ten species of emydids were used (5 batagurines and 5 emydines) which samples all of the karyotypic variation known for the Emydidae. Data from a testudinid and a chelydrid are compared to the emydids. The karyotype of Mauremys and Sacalia is considered representative of the primitive karyotype for this group because of its widespread occurrence in the morphologically primitive Batagurinae and its similarity to that of some testudinids. The emydine karyotype is believed to have evolved from the primitive batagurine karyotype by the deletion of a heterochromatic macrochromosome. Siebenrockiella and Rhinoclemys are karyotypically derived batagurines.