Universidad de Extremadura

The genus Phortica (Diptera: Drosophilidae) includes five species of small flies in Europe. Phortica variegata, the zoophilic fruit fly, is the main vector of Thelazia callipaeda, a zoonotic parasite that is rapidly spreading througout Europe. Despite extensive studies on thelaziosis in animals and humans, there is limited knowledge about the geographical distribution and hovering activity of these vector flies. In 2023, 1,462 Phortica flies were sampled across 12 Spanish provinces, providing new records of Phortica variegata and Phortica oldenbergi. Surprisingly, P. oldenbergi, previously considered a rare Afrotropical species, was prevalent in most regions sampled in Spain. However, Phortica semivirgo was not collected. The abundance of Phortica spp. correlated positively with altitude and certain tree species. Rural oak-wooded areas in central and northern Spain showed the highest densities of P. variegata. Both drosophilid species were analysed morphologically and molecularly, providing new morphological descriptors and sequence barcodes for species identification. Phylogenetic analysis based on COI sequences, showed P. oldenbergi grouped with Asian origin Phortica species, while P. variegata in America was closer to Spanish sequences than those from other European countries. The hovering activity of P. variegata causes significant discomfort to humans during outdoor activities. This paper also reviews the historic records of P. variegata, P. semivirgo and P. oldenbergi in Spain over the last 90 years. This study enhances the understanding of the distribution, identification, ecology, and behaviour of these zoophilic flies in Europe.

The fabrication of new ceramic composites by reactive spark plasma sintering (SPS) from B₄C with 5-30 vol% TaSi₂ aids was investigated, next evaluating some of their mech.-tribol. properties.First, it was found that, because a transient Si melt is formed, TaSi₂ aids reduce significantly the SPS temperature of B₄C (down to 1800°C for 5 vol% TaSi₂ and 1550°C for 30 vol% TaSi₂, temperatures at which pure B₄C is unsinterable).Second, it was found that reactive SPS from B₄C+TaSi₂ results in novel B₁₂(C,Si,B)₃-SiC-TaB₂ composites, with less B₁₂(C,Si,B)₃ and more SiC+TaB₂ with increasing vol% TaSi₂ aids.These composites are all very hard (≥27.5 GPa), some even superhard (∼32-33 GPa), and tougher than monolithic B₄C.In particular, the composite reactively SPS-ed from B₄C with 20 vol% TaSi₂ shows the optimal balance between sinterability (SPS at 1650°C), hardness (∼32.1 GPa), and toughness (∼3.5 MPa·m^1/2).And third, it was found in friction pairs with diamond and ZrO₂ that the optimally SPS-ed composite is highly resistant to the unlubricated sliding wear, undergoing only mild to very mild abrasion with specific wear rates in the order of 10^-6-10^-8 mm³/(N·m).Finally, the performance of these novel composites was compared with that of monolithic B₄C and composites reactively SPS-ed from B₄C with other metal disilicides.

Wildlife conservation and management aims to restore population declines, it is the vulnerable or endangered populations who require the greatest conservation efforts. In this context, non-invasive sampling has been evaluated as an option for reporting prey/predator impact. Galemys pyrenaicus is currently threatened throughout its range, and cohabits with Nemys anomalus, in Extremadura (Spain). Predation by American mink and otter has been suggested, but the first one is considered a serious conservation problem. This study has focused on the use of molecular methods based on RT-PCR and DNA sequencing, as it can inform on how invasive predators are harming the desman or the Iberian water shrew, and how these genetic tools can be used to detect predation.

Five samples (faecal and stomach contents) were received and RT-PCR assays were performed using TaqMan probes simultaneously targeting the cytochrome b (cytb) genes of G. pyrenaicus and N. anomalus, and the presence of both micromammals as prey was assessed. The predator was identified by Sanger sequencing using the nuclear IRBP gene. The assays provide a powerful tool for identification of invasive species, as in this case, but further confirmation by comparative sequence alignment by BLAST search was also necessary.

This study contributes to highlight simultaneously monitor and discriminate predation on specific micromammals with faecal samples of predators. Also supports the use of highly sensitive DNA analysis from samples obtained from predators as an additional methodology to monitor their effects on prey populations.