Role of the Dinaric Karst (western Balkans) in shaping the phylogeographic structure of the threatened crayfish Austropotamobius torrentium

1. This study examines phylogeography and phylogeny of the threatened stone crayfish, Austropotamobius torrentium, in order to elucidate the role of the Dinaric Karst geology in shaping the evolutionary history and genetic diversity of aquatic fauna in the western Balkans. Mitochondrial 16S rRNA and COI genes were partially sequenced from 188 and 159 crayfish, respectively, sampled from 70 localities. Phylogenetic relationships were reconstructed using four methods of phylogenetic inference. Divergence times between phylogroups were estimated in a Bayesian framework, and their demographic history was examined using neutrality tests and mismatch distribution analysis. 2. Seven geographically localised phylogroups separated by pronounced genetic gaps were found. Five of them have a distribution range within the northern‐central Dinaric (NCD) region, while the remaining two include populations from the southern Balkans (SB) and central and south‐eastern Europe (CSE). The oldest divergence event separated two NCD lineages from the rest of populations in the Late Miocene or Early Pliocene. Divergences amongst the five NCD phylogroups and SB + CSE occurred in the Pliocene. The most recent split separated SB and CSE phylogroups during the Late Pliocene. For both genes, uncorrected pairwise divergences between most of the phylogroups (4.1–8.7% for COI and 1.6–4.8% for 16S rRNA) were of the same range as, or higher than, some of the interspecific distances previously reported for the genus Austropotamobius. 3. Geographically isolated and deeply divergent cryptic monophyletic phylogroups within A. torrentium in the NCD region arose in the course of intensification of Neotectonic movements during the Pliocene and the beginning of the Pleistocene and the development of karstification that has heavily fragmented the palaeohydrography of the area. The results confirm a gradual north–south expansion of stone crayfish during the pre‐Pleistocene that preceded the rapid northward post‐glacial re/colonisation of central Europe (CSE phylogroup) through the Danube drainage. 4. Austropotamobius torrentium comprises morphologically cryptic but molecularly distinct taxa. Considering the relatively small geographical areas they inhabit, the NCD phylogroups of stone crayfish should be given the highest conservation priority.     

A TOURNAISIAN BRACHIOPOD FAUNA FROM SOUTH-EAST WALES

Abstract:  An exceptionally preserved fauna within dolomites of the Friars Point Limestone Formation includes the most diverse brachiopod assemblage yet described from the Tournaisian of the British Isles, and the first from Wales. Each of the 16 brachiopod genera includes a single species, of which four are new ( Schellwienella cheuma , Schuchertella subcrona , Composita ptygmation , Fusella extrata ). Associated fossils are corals (one species), bryozoans (two species) and crinoids (one species). Spiriferoideans and schizophorides are numerically dominant, indicative of level-bottom, inner mid-ramp biotopes. Biogeographical comparisons reflect the cosmopolitanism of early Carboniferous brachiopod generic assemblages. Taxonomic comparisons involve selection of lectotypes for Syringothyris exoleta North, 1920, Syringothyris cyrtorhyncha North, 1920, Tylothyris laminosa beta North, 1920, and Tylothyris laminosa gamma North, 1920.     

Proteomic analysis of β-aminobutyric acid priming and abscisic acid – induction of drought resistance in crabapple (Malus pumila): effect on general metabolism, the phenylpropanoid pathway and cell wall enzymes

In a variety of herbaceous, model and crop plants, DL- β -aminobutyric acid (BABA), has been shown to enhance both biotic and abiotic stress resistance by potentiating rather than inducing resistance responses but studies in woody plants are lacking. In the present study, two-dimensional difference in-gel electrophoresis (DIGE) was used to quantify differences in protein abundance in leaf tissue from BABA-treated, abscisic acid (ABA)-treated and untreated (control) plants during a 10 d drought stress. ABA-treated seedlings were most resistant to water loss followed by BABA-treated seedlings and then untreated seedlings. Although some similarity was observed in the proteome of ABA- and BABA-treated seedlings, a dramatic shift in the proteome occurred earlier in ABA-treated seedlings. Some proteins showed almost identical patterns of increase or decrease in abundance in both BABA- and ABA-treated seedlings, supporting the concept that BABA-induced abiotic stress resistance in plants is achieved by potentiating an ABA-regulated pathway. Some proteins, however, were induced or suppressed only in BABA-primed plants, indicating that BABA may also mediate resistance via some ABA-independent pathways. Based on the putative function of the identified proteins, we propose that changes in cell wall enzymes and a suppression of lignin biosynthesis may play a specific role in BABA-primed drought resistance.