Background: Knowledge of animal mitochondrial genomes is very important to understand their molecular evolution as well as for phylogenetic and population genetic studies. The Lepidoptera encompasses more than 160,000 described species and is one of the largest insect orders. To date only nine lepidopteran mitochondrial DNAs have been fully and two others partly sequenced. Furthermore the taxon sampling is very scant. Thus advance of lepidopteran mitogenomics deeply requires new genomes derived from a broad taxon sampling. In present work we describe the mitochondrial genome of the moth Ochrogaster lunifer.

Background: Quaternary climatic oscillations had dramatic effects on species evolution. In northern latitudes, populations had to survive the coldest periods in refugial areas and recurrently colonized northern regions during interglacials. Such a history usually results in a loss of genetic diversity. Populations that did not experience glaciations, in contrast, probably maintained most of their ancestral genetic diversity. These characteristics dramatically affected the present-day distribution of genetic diversity and may influence the ability of species to cope with the current global changes. We conducted a range-wide study of mitochondrial genetic diversity in the pine processionary moth (Thaumetopoea pityocampa/T. wilkinsoni complex, Notodontidae), a forest pest occurring around the Mediterranean Basin and in southern Europe. This species is responding to the current climate change by rapid natural range expansion and can also be accidentally transported by humans. Our aim was to assess if Quaternary climatic oscillations had a different effect across the species' range and to determine if genetic footprints of contemporary processes can be identified in areas of recent introduction.

Testicular descent is a complex multistep embryonic process requiring the interaction between anatomical and hormonal factors. Failure in any of these steps results in cryptorchidism, the most frequent congenital anomaly of the urogenital tract in human males. Evidence for a genetic cause for cryptorchidism is numerous and supported by animal models. In particular, INSL3 and LGR8/GREAT proteins seem to act as ligand and receptor, respectively, and to have a role in gubernaculum development involved in testicular descent. In a cohort of 87 ex-cryptorchid patients and 80 controls, we looked for mutations in INSL3 and LGR8/GREAT genes by sequencing. Patients were classified on the basis of seminal, hormonal, and testicular cytological analyses. We found three mutations in the INSL3 gene in four patients and one LGR8/GREAT mutation in four patients (8 of 87, 9.2%). The eight patients show different phenotypes, ranging from normozoospermia to complete azoospermia, and from bilateral cryptorchidism to retractile testes. Furthermore, the endocrine function of the testis appears normal in all subjects. The findings of our study demonstrate that INSL3-LGR8/GREAT mutations are frequently associated with human cryptorchidism and are maternally inherited. The only clinical consequence of alterations of the INSL3-LGR8/GREAT system seems to be failure of the testis to normally descend in the scrotum during embryonic development, without affecting the spermatogenic and endocrine components of the testis itself.

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The Antarctic silverfish Pleuragramma antarcticum (Nototheniidae) is the most abundant pelagic fish inhabiting Antarctic waters. In this study we investigated, through partial sequencing of the D-loop mitochondrial region, samples collected at four different locations in the Southern Ocean, three in the Atlantic and one in the Pacific sector. Sampling was replicated in two different years at two locations. Sequence analysis showed a remarkably high polymorphism, with 110 haplotypes over the 256 investigated specimens, and about 80% of haplotypes occurring only once. Neutrality tests indicated that all samples were not at mutation-drift equilibrium, and suggested a past population expansion. This result was supported by the presence of a star-like topology in the D-loop gene tree, and by results of mismatch distribution. The start of the expansion was dated, using a specifically calibrated clock, between 111 and 126 thousand years ago. This value corresponds to the start of the cooling period that led to the last glaciation peak, and is in close agreement with a recently suggested range expansion for pelagic Antarctic ecosystems. Analysis of molecular variation indicated a small, though highly significant, value of differentiation between samples. This result, together with the lack of association between clades and geographical locations, indicates a weak population structure for the species.