Melting pots and hotspots: genetic variation within Acanthodactylus erythrurus (Reptilia: Lacertidae) from the Iberian Peninsula

Identification of high levels of intraspecific genetic variability is common among assessments of reptiles from the Iberian Peninsula, conforming to the “refugia within refugia” hypothesis. Divergent genetic lineages are often found to be allopatric, or with limited contact or hybrid zones; such zones are more widely reported in Northern Europe, leading to the “melting pots not hotspots” hypothesis. However, population level sampling is needed to determine if divergent lineages overlap, something that is often missing in phylogenetic studies. Mitochondrial genetic diversity was assessed within the lacertid lizard Acanthodactylus erythrurus across the Iberian Peninsula. Not only were highly divergent lineages recovered in the southern region, but also considerable admixture of these was identified, particularly in northern populations. This has implications for biogeographic scenarios, with patterns typically identified at a larger scale emerging within a single European southern refugium. It also indicates that divergent mtDNA lineages appear to freely mix, at least within this species, which has taxonomic implications.

Intraspecific mitogenomics of three marine species-at-risk: Atlantic, spotted, and northern wolffish (Anarhichas spp.)

High-resolution mitogenomics of within-species relationships can answer such phylogeographic questions as how species survived the most recent glaciation, as well as identify contemporary factors such as physical barriers, isolation, and gene flow. We examined the mitogenomic population structure of three at-risk species of wolffish: Atlantic (Anarhichas lupus), spotted (A. minor), and northern (A. denticulatus). These species are extensively sympatric across the North Atlantic but exhibit very different life history strategies, a combination that results in concordant and discordant patterns of genetic variation and structure. Wolffish haplogroups were not structured geographically: Atlantic and spotted wolffish each comprised three shallow clades, whereas northern wolffish comprised two deeper but unstructured lineages. We suggest that wolffish species survived in isolation in multiple glacial refugia, either refugia within refugia (Atlantic and spotted wolffish) or more distant refugia (northern wolffish), followed by secondary admixture upon post-glacial recolonisation of the North Atlantic.

STUDIES ON THE GLACIAL REFUGIA OF FOREST TREES ON BALKAN PENINSULA

During the Ice Age the southern parts of Europe, including Balkans, remained practically unaffected by glaciations and served as refugia for many plant and animal species. However, even within the framework of each glacial refugia, the conditions were not homogeneous and isolated “hot spots” appeared that had led to “refugia within refugia”. The territory of Balkan Peninsula could be subdivided into different zones, which are of different importance from the point of view of formation of the present day biodiversity. Tree species are particularly suitable for studies of inter-glacial and post-glacial migrations, due to their important ecological role in shaping the environmental conditions. Today, studying of these issues is greatly facilitated by introducing of genetic markers, allowing precise tracing of post-glacial migrations. The topic is less studied in the Balkan Peninsula, even though the region is considered one of the most important European refugia. A brief review of the more important studies in this respect is presented and the prospects and importance of such studies is discussed.

Refugia within refugia: in situ speciation and conservation of threatened Bertmainius (Araneae : Migidae), a new genus of relictual trapdoor spiders endemic to the mesic zone of south-western Australia

The trapdoor spider family Migidae has a classical Gondwanan distribution and is found on all southern continents except the Indian region. The Australian fauna consists of three genera including Moggridgea O. P. Cambridge from south-western Australia and Kangaroo Island, South Australia; Moggridgea is otherwise widespread throughout Africa. The sole named species of Moggridgea from Western Australia, M. tingle Main, and its unnamed relatives are the subject of the present paper, which was stimulated by concern for the long-term persistence of populations, and the discovery of deep genetic divergences between populations. A phylogeny of the Western Australian species relative to African and South Australian Moggridgea was generated using molecular COI and ITS rDNA data, and based on both molecular and morphological criteria we conclude that the Western Australian taxa should be removed from Moggridgea and transferred to a new genus, Bertmainius. The seven species are delimited using both morphological and molecular criteria: B. tingle (Main) (the type species), and six new species, B. colonus, B. monachus, B. mysticus, B. opimus, B. pandus and B. tumidus. All seven species are considered to be threatened using IUCN criteria, with the major threatening processes being inappropriate fire regimes and climate change.