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1.
Mol Phylogenet Evol ; 55(1): 26-37, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19995610

ABSTRACT

The few studies available on Tyrrhenian land snails support high diversification in the Italian Peninsula and groups structured mainly by vicariant events. Here we investigated the phylogeny of a conchologically diversified group of Tyrrhenian land snails assigned to the genera Marmorana and Tyrrheniberus. We constructed a molecular phylogeny by sequencing two commonly used mtDNA genes (cytochrome oxidase I and the large ribosomal subunit). We also carried out conchological and anatomical analysis. Morphological (shell and genitalia) and genetic data (mitochondrial genes) showed paraphyly of Marmorana. Plio-Pleistocene events in the Tyrrhenian area may have structured relationships between species at regional scale while isolation by distance probably played a role in diversification between populations on a local scale. Continental populations experienced dispersal during interglacial periods and fragmentation and reduction during the dry cold climatic phases. Areas inhabited by Apennine Marmorana could represent relict and/or glacial refugia, with extinction in some areas along the Apennines and survival in the south. The results support a reassessment of taxonomy both at genus and species level and call for further analysis.


Subject(s)
Evolution, Molecular , Phylogeny , Snails/genetics , Analysis of Variance , Animals , DNA, Mitochondrial/genetics , Genetics, Population , Geography , Models, Genetic , Sequence Analysis, DNA , Snails/anatomy & histology , Snails/classification
2.
C R Biol ; 330(2): 113-25, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17303538

ABSTRACT

The scorpion of Montecristo Island (Tuscan Archipelago, Italy): Euscorpius carpathicus oglasae Di Caporiacco, 1950, is a poorly known taxon. We redescribe and illustrate the insular endemism of E. c. oglasae for the first time, and elevate this subspecies to the rank of species following a thorough study of the comparative morphology of 372 specimens (including 7 related taxa). Euscorpius oglasae stat. nov. is an oligotrichous form that differs from the related species by the inner proximal surface of pedipalp movable finger, with a reduced lobe and a slightly swollen telson vesicle in males. Attention was given to the analysis of the hemispermatophore and peg sensilla of pectens. The hemispermatophore is small, with the basal lobe bearing a very short spine. We also discuss aspects of the ecology, conservation and biogeography of this species.


Subject(s)
Scorpions , Animals , Female , Male , Mediterranean Islands , Scorpions/anatomy & histology , Scorpions/classification , Species Specificity
3.
Mol Phylogenet Evol ; 43(2): 502-14, 2007 May.
Article in English | MEDLINE | ID: mdl-17150377

ABSTRACT

Euscorpius tergestinus (C.L. Koch, 1837), Euscorpius concinnus (C.L. Koch, 1837) and Euscorpius sicanus (C.L. Koch, 1837), three presumed closely related species belonging to the "carpathicus group", occur in the Italian peninsula with a largely parapatric distribution and some zones of range overlap. These areas of sympatry represent interesting opportunities to investigate species boundaries in natural populations. Here we report on a study exploring genetic variation in sympatric populations of the three species from central Tuscany. Additional collecting sites, from different localities across Italy, were also included in the analysis in order to explore the phylogeographic structure of the group. Species boundaries and evolutionary relationships were examined by sequence comparison of mitochondrial 16S rRNA and nuclear ITS-1 rRNA gene fragments. DNA sequence data show no evidence of genetic introgression between different evolutionary lineages from the area of range overlap, suggesting the absence of either past or ongoing inter-specific gene flow. It is therefore probable that reproductive barriers exist, preventing gene pools from amalgamating. Furthermore, our results support the recent morphological distinction of E. tergestinus, as traditionally classified, into two different species: E. tergestinus and E. concinnus. Both mitochondrial and nuclear sequence data clearly indicate that the two taxa represent well-supported and deeply divergent lineages. Euscorpius sicanus seems to represent a monophyletic taxon, but the high genetic variability observed within this taxon calls for future investigation. The present distribution patterns across the Italian peninsula were mainly interpreted as the consequence of climatic oscillations.


Subject(s)
Phylogeny , Scorpions/classification , Scorpions/genetics , Animals , DNA, Mitochondrial/genetics , DNA, Ribosomal Spacer/genetics , Genetic Variation , Italy , RNA, Ribosomal, 16S/genetics
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