An exceptionally long paleoseismic record of a slow-moving fault: the Alhama de Murcia fault (Eastern Betic Shear Zone, Spain)

Most catastrophic earthquakes occur along fast-moving faults, although some of them are triggered by slow-moving ones. Long paleoseismic histories are infrequent in the latter faults. Here, an exceptionally long paleoseismic record (more than 300 k.y.) of a slow-moving structure is presented for the southern tip of the Alhama de Murcia fault (Eastern Betic shear zone), which is characterized by morphological expression of current tectonic activity and by a lack of historical seismicity. At its tip, the fault divides into a splay with two main faults bounding the Góñar fault system. At this area, the condensed sedimentation and the distribution of the deformation in several structures provided us with more opportunities to obtain a complete paleoseismic record than at other segments of the fault. The tectonic deformation of the system was studied by an integrated structural, geomorphological, and paleoseismological approach. Stratigraphic and tectonic features at six paleoseismic trenches indicate that old alluvial units have been repeatedly folded and thrusted over younger ones along the different traces of the structure. The correlation of the event timing inferred for each of these trenches and the application of an improved protocol for the infrared stimulated luminescence (IRSL) dating of K-feldspar allowed us to constrain a paleoseismic record as old as 325 ka. We identifi ed a minimum of six possible paleoearthquakes of Mw = 6-7 and a maximum mean recurrence interval of 29 k.y. This provides compelling evidence for the underestimation of the seismic hazard in the region

The ER-membrane transport system is critical for intercellular trafficking of the NSm movement protein and Tomato Spotted Wilt Tospovirus

Plant viruses move through plasmodesmata to infect new cells. The plant endoplasmic reticulum (ER) is interconnected among cells via the ER desmotubule in the plasmodesma across the cell wall, forming a continuous ER network throughout the entire plant. This ER continuity is unique to plants and has been postulated to serve as a platform for the intercellular trafficking of macromolecules. In the present study, the contribution of the plant ER membrane transport system to the intercellular trafficking of the NSm movement protein and Tomato spotted wilt tospovirus (TSWV) is investigated. We showed that TSWV NSm is physically associated with the ER membrane in Nicotiana benthamiana plants. An NSm-GFP fusion protein transiently expressed in single leaf cells was trafficked into neighboring cells. Mutations in NSm that impaired its association with the ER or caused its mis-localization to other subcellular sites inhibited cell-to-cell trafficking. Pharmacological disruption of the ER network severely inhibited NSm-GFP trafficking but not GFP diffusion. In the Arabidopsis thaliana mutant rhd3 with an impaired ER network, NSm-GFP trafficking was significantly reduced, whereas GFP diffusion was not affected. We also showed that the ER-to-Golgi secretion pathway and the cytoskeleton transport systems were not involved in the intercellular trafficking of TSWV NSm. Importantly, TSWV cell-to-cell spread was delayed in the ER-defective rhd3 mutant, and this reduced viral infection was not due to reduced replication. On the basis of robust biochemical, cellular and genetic analysis, we established that the ER membrane transport system serves as an important direct route for intercellular trafficking of NSm and TSWV

Ecological constraints from incumbent clades drive trait evolution across the tree-of-life of freshwater macroinvertebrates

The rates of species and trait diversification vary across the Tree‐of‐Life and over time. Whereas species richness and clade age generally are decoupled, the correlation of accumulated trait diversity of clades (trait disparity) with clade age remains poorly explored. Total trait disparity may be coupled with clade age if the growth of disparity (disparification) within and across clades is continuous with time in an additive niche expansion process (linear‐cumulative model), or alternatively if the rate of trait disparification varies over time and decreases as ecological space becomes gradually saturated (disparity‐dependent model). Using a clock‐calibrated phylogenetic tree for 143 freshwater macroinvertebrate families and richness and trait databases covering > 6400 species, we measured trait disparity in 18 independent clades that successively transitioned to freshwater ecosystems and analyzed its relation with clade age. We found a positive correlation between clade age and total disparity within clades, but no relationship for most individual traits. Traits unique to freshwater lifestyle were highly variable within older clades, while disparity in younger clades shifted towards partially terrestrial lifestyles and saline tolerance to occupy habitats previously inaccessible or underutilized. These results argue that constraints from incumbent lineages limit trait disparity in younger clades that evolved for filling unoccupied regions of the trait space, which suggests that trait disparification may follow a disparity‐dependent model. Overall, we provide an empirical pattern that reveals the potential of the disparity‐dependent model for understanding fundamental processes shaping trait dynamics across the Tree‐of‐Life

Advances in the use of molecular tools in ecological and biodiversity assessment of aquatic ecosystems

Conservation and sustainable management of aquatic ecosystems is a priority in environmental programs worldwide. However, these aims are highly dependent on the efficiency, accuracy and cost of existent methods for the detection of keystone species and monitoring of biological communities. Rapid advances in eDNA, barcoding and metabarcoding promoted by high-throughput sequencing technologies are generating millions of sequences in a fast way, with a promising cost reduction, and overcoming some difficulties of the traditional taxonomic approaches. This paper provides an updated broad perspective of the current developments in this dynamic field presented in the special session (SS) "The use of molecular tools in ecological and biodiversity assessment of aquatic ecosystems" of the XIX Congress of the Iberian Association of Limnology (AIL2018), held in Coimbra, Portugal.Developments presented are mainly focused on the Iberian Peninsula (Portugal and Spain, including Atlantic Macaronesian islands) but include studies in France, Germany, Finland, Russia (Siberia) and South America. The networks within which these researchers are involved are yet even broader, profiting from existing molecular facilities, and traditional taxonomic expertise, which can be viewed as a characteristic of this new research area. It was evident in the SS that the use of molecular tools is widespread, being used to study a diversity of aquatic systems, from rivers' headwaters to estuaries and coastal lagoons, and volcanic, mountain and frozen lakes to hot springs. The organisms targeted are likewise varied and include fish, macroinvertebrates, meiofauna, microalgae such as diatoms and dinoflagellates, other protists, fungi, and bacteria (cyanobacteria and other). Some studies address the whole biodiversity (i.e., all species present independently of the taxonomic group) from environmental samples of water, biofilms and preservative solution from field samples (e.g., ethanol from macroinvertebrate samples). Great advances were acknowledged inWe are grateful to all participants of the special session "The use of molecular tools in ecological and biodiversity assessment of aquatic ecosystems" for the productive discussions during the AIL 2018 meeting (XIX Iberian Association of Limnology meeting in Coimbra (Portugal, June 2018). M.J. Feio is supported by MARE strategic program (UID/MAR/04292/2013); SFP Almeida is supported by GeoBioTec strategic program UID/GEO/04035/2019. R. Cordeiro was supported by a Ph.D. Grant (M3.1.a/F/017/2011) from Fundo Regional da Ciencia e Tecnologia (FRCT); A.F. Filipe and A. Garcia-Raventos were supported by FRESHING Project "Next-generation biomonitoring: freshwater bioassessment and species conservation improved with metagenomics" funded by the Portuguese Foundation for Science and Technology (FCT) and COMPETE (PTDC/AAG-MAA/2261/2014 -POCI-01-0145-FEDER-356 016824); F.M.S. Martins was supported by a FCT PhD grant (SFRH/BD/104703/2014); A.R. Calapez was supported by a grant from the FCT-PhD programme FLUVIO (PD\BD\52510\2014); A.M. Pujante acknowledges the BIOWAT-KIT_E!11892 Eurostars project; Maria Fais and Sofia Duarte were supported, respectively, by a PhD (SFRH/BD/113547/2015) and a post-doc fellowship (SFRH/BPD/109842/2015), from FCT; and C. Murria acknowledges the Fundacio Aigues de Barcelona for funding his research