Population Genetic Structure and Phylogeography of Co-Distributed Pachymeniopsis Species (Rhodophyta) along the Coast of Korea and Japan

Inferring phylogeographic patterns of macroalgal species is essential for understanding the population structure and for the conservation of macroalgal species. In this study, the phylogeographic patterns of two co-distributed macroalgal species along the coast of Korea and Japan, Pachymeniopsis lanceolata and Pachymeniopsis elliptica, were analyzed. Pachymeniopsis lanceolata (215 specimens from 36 sites) and P. elliptica (138 specimens from 24 sites), using the plastid rbcL gene, are characterized by fifteen and six haplotypes, respectively. Mitochondrial COI-5P gene sequences revealed a low variation for both species. An analysis of molecular variance (AMOVA), pairwise FSTcomparisons, and haplotype networks based on the rbcL data suggest a weak genetic differentiation of both species. The shared haplotypes (P. lanceolata: LR01; P. elliptica: ER01) found in the entire sampling range indicate that these two Pachymeniopsis species can disperse over long distances along the coast of Korea and Japan. Despite the similar phylogeographic pattern, our results suggest that P. lanceolata has a higher genetic diversity, with a wider distribution along the Korean Peninsula than P. elliptica. Moreover, it is adapted to low sea surface temperatures and survived in more of the available habitats during periods of climatic change, whereas P. elliptica is less adaptable and more susceptible to environmental disturbance. This phylogeographic study provides a rationale for the conservation of the wild Pachymeniopsis population.

What's in a mass?

This short essay pretends to make the reader reflect on the concept of biological mass and on the added value that the determination of this molecular property of a protein brings to the interpretation of evolutionary and translational snake venomics research. Starting from the premise that the amino acid sequence is the most distinctive primary molecular characteristics of any protein, the thesis underlying the first part of this essay is that the isotopic distribution of a protein's molecular mass serves to unambiguously differentiate it from any other of an organism's proteome. In the second part of the essay, we discuss examples of collaborative projects among our laboratories, where mass profiling of snake venom PLA2 across conspecific populations played a key role revealing dispersal routes that determined the current phylogeographic pattern of the species.

Cryptic survival and an unexpected recovery of the long-tailed mayfly Palingenia longicauda (Olivier, 1791) (Ephemeroptera: Palingeniidae) in Southeastern Europe.

Once widespread in the large European rivers, Palingenia longicauda underwent a drastic range contraction as a result of the intense pollution and hydromorphological interventions of the 19th and 20th centuries. For the last decades it was considered to be restricted only to the Tisa River and its tributaries, and to the Rba&aacute River, but new reports indicated its presence in the Danube River in Hungary, in the Danube Delta in Romania and Ukraine, and in the Prut River in the Republic of Moldova. The objective of this study is to analyze the phylogeographic pattern between the two main eco-regions (Pannon and Pontic) of the species distribution, based on the combined mitochondrial COI (472 bp) and 16S (464 bp) sequences generated for individuals collected in Romania and Ukraine, and from publicly available ones, representing the Tisa catchment populations. The presence of viable populations in the Danube Delta and on the Prut River in Romania is confirmed, and additional presence on the Mureș and Bega rivers from Romania, and on the Styr and Horyn rivers in Northern Ukraine is shown. The phylogeographic results indicate that the presence of the analyzed populations are not the result of recent founding events from the Pannon region, confirming the survival and expansion of cryptic local lineages. The recent recovery of the species may be related to the improvement of water quality as a result of the implementation of the EU Water Framework Directive and the EU Floods Directive after 2000.

Phylogeographic distribution of rhizobia nodulating common bean (Phaseolus vulgaris L.) in Ethiopia

ABSTRACT Rhizobia are soilborne bacteria that form symbiotic relations with legumes and fix atmospheric nitrogen. The nitrogen fixation potential depends on several factors such as the type of host and symbionts and on environmental factors that affect the distribution of rhizobia. We isolated bacteria nodulating common bean in Southern Ethiopia to evaluate their genetic diversity and phylogeography at nucleotide, locus (gene/haplotype) and species levels of genetic hierarchy. Phylogenetically, eight rhizobial genospecies (including previous collections) were determined that had less genetic diversity than found among reference strains. The limited genetic diversity of the Ethiopian collections was due to absence of many of the Rhizobium lineages known to nodulate beans. Rhizobium etli and Rhizobiumphaseoli were predominant strains of bean-nodulating rhizobia in Ethiopia. We found no evidence for a phylogeographic pattern in strain distribution. However, joint analysis of the current and previous collections revealed differences between the two collections at nucleotide level of genetic hierarchy. The differences were due to genospecies Rhizobium aethiopicum that was only isolated in the earlier collection.

Molecular evidence reveals introduced populations of Eiseniella tetraedra (Savigny, 1826) (Annelida, Lumbricidae) with European origins from protected freshwater ecosystems of the southern Alborz Mountains

The presence of exotic earthworms has recently become a major concern and drawn significant attention to their potential effects on ecosystems and native invertebrate fauna. Although the occurrence of invasive annelids has been well recorded, their settlement in Iran is poorly documented. To investigate the biodiversity of aquatic Oligochaeta and to assess the presence of possible exotic species, DNA barcoding using the mitochondrial cytochrome c oxidase subunit 1 (COI) gene was conducted in two major protected rivers (Jajroud, Karaj) of the southern Alborz Mountains. As a result, new lineages of Tubifex, Haplotaxis and Lumbriculus were identified from Iran. Moreover, a semiaquatic lumbricid species, Eiseniella tetraedra, was unexpectedly found to be the most abundant species. The analyses showed the presence of six divergent lineages of E. tetraedra occurring in individual rivers. The presence of identical haplotypes shared between European, North American, Australian and Iranian localities, the sympatric accumulation of several distinct intraspecific lineages in the same rivers and the lack of a phylogeographic pattern reinforce the hypothesis of a possible inadvertent anthropogenic introduction. The relative abundance of lineages indicates a significant decline in the abundance of native oligochaetes, which may be linked to the preponderance of recently introduced European populations of E. tetraedra, probably mediated through human activities.

Population Genetic Structure and Demography of the Critically Endangered Chequered Blue Butterfly (Scolitantides orion) in a Highly Isolated Part of Its Distribution Range

Scolitantides orion is a butterfly species threatened in many European countries. In Poland, it survived in a single highly isolated area (Vistula River valley), which is an example of the dramatic decline in the population number. We studied the two largest remaining populations inhabiting opposite banks of the river. Mark-release-recapture studies showed that both populations were small, and they fluctuated in numbers, but adult individuals were twice as numerous on the western site. Genetic analyses were carried out using a mitochondrial (COI, ND5) and nuclear markers (Wgl, EF-1α, and microsatellite loci). We found out that genetic variation was low at both sites but higher in the smaller eastern population. This pattern is likely to be better explained by past distribution, when the butterfly, as a continental species used to be much more widespread in the east. However, the genetic differentiation between populations was low. This could suggest that the existing gene flow is facilitated by dominant regional wind direction, which may also contribute to a better genetic condition of the western population. Finally, a comparison of the obtained COI sequences with others available enabled us to reveal the phylogeographic pattern of the S. orion from different localities within its range.