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- Distinctive genetic signatures of two fairy shrimp species with overlapping ranges in Iberian temporary pondsPublication . Lopes Da Cunha, Regina; Sala, Jordi; Machado, Margarida; Boix, Dani; Madeira, Celine; Madeira, Pedro M.; Cristo, Margarida; Cancela Da Fonseca, Luís; Castilho, RitaTemporary lentic water bodies host biotic assemblages adapted to the transient nature of these freshwater habitats. Fairy shrimps (Crustacea, Branchiopoda, Anostraca) are one of the most important biological components of these unique environments and have a fossil record dating back to the Middle Jurassic (>150 million years). Some anostracan species show a geographically restricted distribution, whereas others are widely dispersed. We aimed to investigate the relationship between different geographic extents and patterns of genetic structure in species of Anostraca. Following this objective, we selected two species with contrasting ranges but overlapping geographic distributions and similar life-history traits in the study area. We analysed additional information that, from an ecological (e.g. egg-bank, niche breadth, and pond connectivity) and evolutionary (e.g. crown-group age of each species) perspective, may explain the obtained phylogeographic patterns. Between 2005 and 2018, we sampled two species of fairy shrimps (309 specimens of Branchipus cortesi and 264 specimens of Tanymastix stagnalis) from 53 temporary ponds of Portugal. We added five other locations from Spain and France to include other European locations for T. stagnalis. Additionally, we also sampled Branchipus schaefferi from two temporary water bodies (Spain and Morocco) to include in the dating analysis. Reconstructed phylogenies based on mitochondrial sequence data indicate the existence of deeply divergent clades with an unequivocal phylogeographic structure in T. stagnalis and shallower divergences in B. cortesi with a less clear geographic correspondence. We found evidence of frequent local and rare long-distance dispersal events in both species and limited intermediate dispersal, which was more common in B. cortesi. A Bayesian dating analysis using the Branchiopoda fossil record estimated the age of the most recent common ancestors of T. stagnalis and B. cortesi at 32.4 and 12.8 million years, respectively. Haplotype accumulation curves indicated that only a portion of the genetic composition of the species was sampled on each hydroperiod and showed the existence of large, genetically diverse egg banks that remain in the soil. These egg banks represent a genetic reservoir that guarantees the survival of the species because active populations from different hydroperiods may be genetically different and adapt to a changing environment. We hypothesise that the contrasting phylogeographic patterns displayed by the two fairy shrimp species may result from: (1) the earlier age of the most recent common ancestor of T. stagnalis, as older species have more time to accumulate mutations and, thus, are expected to exhibit higher genetic differentiation among populations; (2) slight differences in adult behaviour, life-history traits and cyst morphologies of T. stagnalis and B. cortesi favouring different animal dispersal vectors with distinct dispersal abilities. Therefore, phylogeographic patterns may be explained by both evolutionary and ecological processes, which operate in different time scales.
- Defining the importance of landscape metrics for large branchiopod biodiversity and conservation: the case of the Iberian Peninsula and Balearic IslandsPublication . Sala, Jordi; Gascon, Stephanie; Cunillera-Montcusi, David; Alonso, Miguel; Amat, Francisco; Cancela Da Fonseca, Luís; Cristo, M.; Florencio, Margarita; Garcia-de-Lomas, Juan; Machado, Margarida; Rosa Miracle, Maria; Miro, Alexandre; Luis Perez-Bote, Jose; Lluis Pretus, Joan; Prunier, Florent; Ripoll, Javier; Rueda, Juan; Sahuquillo, Maria; Serrano, Laura; Ventura, Marc; Verdiell-Cubedo, David; Boix, DaniThe deficiency in the distributional data of invertebrate taxa is one of the major impediments acting on the bias towards the low awareness of its conservation status. The present study sets a basic framework to understand the large branchiopods distribution in the Iberian Peninsula and Balearic Islands. Since the extensive surveys performed in the late 1980s, no more studies existed updating the information for the whole studied area. The present study fills the gap, gathering together all available information on large branchiopods distribution since 1995, and analysing the effect of human population density and several landscape characteristics on their distribution, taking into consideration different spatial scales (100 m, 1 km and 10 km). In overall, 28 large branchiopod taxa (17 anostracans, 7 notostracans and 4 spinicaudatans) are known to occur in the area. Approximately 30% of the sites hosted multiple species, with a maximum of 6 species. Significant positive co-occurring species pairs were found clustered together, forming 4 different associations of large branchiopod species. In general, species clustered in the same group showed similar responses to analysed landscape characteristics, usually showing a better fit at higher spatial scales.