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An accurate species‐level taxonomy is paramount for biogeographical research, and conversely, biogeographical data are of importance for species delimitation. We here review recent developments and future perspectives of taxonomy of direct relevance for biogeographers. The understanding that species are independently evolving segments of population‐level lineages, the rise of integrative approaches to delimit such lineages, and the advent of high‐throughput sequencing have considerably renewed the discipline of taxonomy. Using genome‐scale molecular datasets, the extent of admixture across hybrid zones can now be effectively assessed and the evolutionary independence of lineages inferred, leading to more reliable and comparable species delimitation criteria. Substantially divergent but admixing phylogeographical lineages can conveniently be named as subspecies, thus avoiding taxonomic oversplitting and taxonomic inflation. At the same time, comprehensive DNA barcoding and DNA metabarcoding efforts are uncovering an enormous proportion of undiscovered biotic diversity, and we encourage the development of bioinformatic pipelines that combine high‐throughput species discovery and delimitation with diagnosis and scientific naming, to approach a biotic inventory of the globe without abandoning the established Linnaean system. [ABSTRACT FROM AUTHOR]

A recent revision of the anacondas (Serpentes: Boidae: Eunectes), with the description of a new species of green anaconda, generated extensive publicity, but also provoked considerable controversy due to inadequacies of the evidence used and errors in nomenclature. We here use the case of this problematic publication to: (i) highlight common issues affecting species delimitations, especially an over-reliance on mitochondrial DNA data, and reiterate best practices; (ii) reanalyse the data available for anacondas to establish the true current state of knowledge and to highlight lines of further research; and (iii) analyse the nomenclatural history and status of the genus. While our analysis reveals significant morphological variation in both green and yellow anacondas, denser sampling and an analysis of informative nuclear markers are required for meaningful species delimitation in Eunectes. Tracing the history of name-bearing types establishes Trinidad as the type locality for Boa murina Linnaeus, 1758 and allows identification of the extant lectotype for the species. Finally, we emphasize the responsibility of both journals and authors to ensure that published taxonomic work meets the burden of evidence required to substantiate new species descriptions and that species are named in compliance with the rules of zoological nomenclature. [ABSTRACT FROM AUTHOR]

Traditional methods of phylogenetic reconstruction and species delimitation may be impeded by frequent hybridization among lineages. In this study, we conducted phylogenetic and clustering analyses of ddRAD genomic data on the entire genus Salamandra, which includes six species and over 25 subspecies of terrestrial salamanders. We expanded previous datasets to include missing subspecies and incorporated new samples, with an emphasis on secondary contact zones. Results obtained from a full dataset of 392 individuals (356,874 bp; 24,192 SNPs) were compared with those obtained after excluding substantially admixed individuals (n = 95; 835,467 bp; 51,557 SNPs) to explore the consequences of introgression on phylogenetic inference and taxonomic arrangement of subspecies. We found conflicting phylogenetic placements for taxa represented by many admixed individuals (identified by clustering ancestries). In contrast, a time-calibrated tree constructed without hybrids largely agrees with previous phylogenetic hypotheses. Within S. atra, we found paraphyly of S. atra atra, suggesting an additional candidate subspecies. Within S. infraimmaculata, two lineages are assignable to known subspecies and we additionally identified a third, deeply diverged lineage sampled near the Turkish/Syrian border. In S. algira, we found limited admixture between the subspecies S. a. tingitana and S. a. splendens despite their geographic proximity. Finally, within S. salamandra, we detected significant levels of hybridization between subspecies, which blurred their phylogenetic relationships, although the removal of admixed samples in subset analyses clarified the situation in most cases. Monophyly was recovered for subspecies that were previously found paraphyletic, including S. s. salamandra, S. s. gallaica, and S. s. fastuosa. Salamandra s. "alfredschmidti" was confirmed to be a junior synonym of S. s. bernardezi. Previously disputed subspecies, like S. s. "molleri" and S. s. "hispanica", correspond to separated lineages but are affected by admixture with other lineages. Further newly identified candidate subspecies in S. salamandra included a southern lineage within S. s. wer-neri and a western lineage within S. s. bernardezi. Finally, we re-evaluate the status of recognized subspecies in Salamandra, based on evidence from multiple delimitation criteria. Given that the evolutionary history could not be resolved for all subspecies, we highlight taxa within Salamandra that warrant further molecular examination and taxonomic revision, notably within the S. s. gallaica/"molleri"/bejarae complex. This study illustrates the impact of hybridization in phylogenetic analyses and its downstream effects in the identification of conservation units and their naming in the Linnean classification. [ABSTRACT FROM AUTHOR]

Aim: We aimed to describe the neurosonological findings related to cerebral hemodynamics acquired using transcranial Doppler and to determine the frequency of elevated ICP by optic nerve sheath diameter (ONSD) measurement in patients with severe coronavirus disease (COVID-19) hospitalized in the intensive care unit of a national referral hospital in Peru. Methods: We included a retrospective cohort of adult patients hospitalized with severe COVID-19 and acute respiratory failure within the first 7 days of mechanical ventilation under deep sedoanalgesia, with or without neuromuscular blockade who underwent ocular ultrasound and transcranial Doppler. We determine the frequency of elevated ICP bymeasuring the diameter of the optic nerve sheath, choosing as best cut-off value a diameter equal to or >5.8mm. We also determine the frequency of sonographic patterns obtained by transcranial Doppler. Through insonation of the middle cerebral artery. Likewise, we evaluated the associations of clinical, mechanical ventilator, and arterial blood gas variables with ONSD =5.8mm and pulsatility index (PI) =1.1. We also evaluated the associations of hemodynamic findings and ONSD with mortality the effect size was estimated using Poisson regression models with robust variance. Results: This study included 142 patients. The mean age was 51.39 ± 13.3 years, and 78.9% of patients were male. Vasopressors were used in 45.1% of patients, and mean arterial pressure was 81.87 ± 10.64 mmHg. The mean partial pressure of carbon dioxide (PaCO2) was elevated (54.08 ± 16.01 mmHg). Elevated intracranial pressure was seen in 83.1% of patients, as estimated based on ONSD =5.8mm. A mortality rate of 16.2% was reported. In the multivariate analysis, age was associated with elevated ONSD (risk ratio [RR] = 1.07). PaCO2 was a protective factor (RR = 0.64) in the cases of PI = 1.1. In the mortality analysis, the mean velocity was a risk factor for mortality (RR = 1.15). Conclusions: A high rate of intracranial hypertension was reported, with ONSD measurement being themost reliablemethod for estimation. The increase in ICP measured by ONSD in patients with severe COVID-19 on mechanical ventilation is not associated to hypercapnia or elevated intrathoracic pressures derived from protective mechanical ventilation. [ABSTRACT FROM AUTHOR]

Background: Long-term follow-up of cerebral aneurysms treated with the Silk Vista Baby (SVB) flow diverter is lacking. This study aimed to assess the technical success, procedural safety, and efficacy of the SVB (Balt, Montmorency, France) for the treatment of intracranial aneurysms in small cerebral vessels over a midto long-term follow-up. Methods: We retrospectively analyzed a prospectively maintained database of patients treated with the SVB between September 2018 and June 2021. Data regarding patient demographics, aneurysm characteristics, and technical procedures were also collected. Angiographic and clinical findings were recorded during the procedure and over a period of at least 12 months. Results: Angiographic and clinical follow-up data were available for 50 patients/50 aneurysms. The procedural complication rate was 8%. At 12 months, the final results showed a technical success rate of 100%, the re rupture rate was 0%, neuromorbidity and mortality rates of 4 and 0%, respectively, and an almost complete occlusion rate of 94%. Conclusion: Treatment of complex intracranial aneurysms with the SVB was safe and effective. Long-term results showed high rates of adequate and stable occlusions. [ABSTRACT FROM AUTHOR]

Scientific names permit humans and search engines to access knowledge about the biodiversity that surrounds us, and names linked to DNA sequences are playing an ever-greater role in search-and-match identification procedures. Here, we analyze how users and curators of the National Center for Biotechnology Information (NCBI) are flagging and curating sequences derived from nomenclatural type material, which is the only way to improve the quality of DNA-based identification in the long run. For prokaryotes, 18,281 genome assemblies from type strains have been curated by NCBI staff and improve the quality of prokaryote naming. For Fungi, type-derived sequences representing over 21,000 species are now essential for fungus naming and identification. For the remaining eukaryotes, however, the numbers of sequences identifiable as type-derived are minuscule, representing only 739 species of arthropods, 1542 vertebrates, and 125 embryophytes. An increase in the production and curation of such sequences will come from (i) sequencing of types or topotypic specimens in museum collections, (ii) the March 2023 rule changes at the International Nucleotide Sequence Database Collaboration requiring more metadata for specimens, and (iii) efforts by data submitters to facilitate curation, including informing NCBI curators about a specimen's type status. We illustrate different type-data submission journeys and provide best-practice examples from a range of organisms. Expanding the number of type-derived sequences in DNA databases, especially of eukaryotes, is crucial for capturing, documenting, and protecting biodiversity. [ABSTRACT FROM AUTHOR]

Tropical ecosystems are challenging for pinnipeds due to fluctuating food availability. According to previous research, the Galapagos sea lion (GSL, Zalophus wollebaeki) adopts trophic flexibility to face such conditions. However, this hypothesis comes from studies using traditional methods (hard‐parts analysis of scat and isotopic analysis from tissue). We studied the diet of five rookeries in the southeastern Galapagos bioregion (which harbors the highest GSL density), via DNA‐metabarcoding of scat samples. The DNA‐metabarcoding approach may identify consumed prey with a higher taxonomic resolution than isotopic analysis, while not depending on hard‐parts remaining through digestion. Our study included five different rookeries to look for evidence of trophic flexibility at the bioregional level. We detected 98 prey OTUs (124 scats), mostly assigned to bony‐fish taxa; we identified novel prey items, including a shark, rays, and several deep‐sea fish. Our data supported the trophic flexibility of GSL throughout the studied bioregion since different individuals from the same rookery consumed prey coming from different habitats and trophic levels. Significant diet differentiations were found among rookeries, particularly between Punta Pitt and Santa Fe. Punta Pitt rookery, with a more pronounced bathymetry and lower productivity, was distinguished by a high trophic level and consumption of a high proportion of deep‐sea prey; meanwhile, Santa Fe, located in more productive, shallow waters over the shelf, consumed a high proportion of epipelagic planktivorous fish. Geographic location and heterogeneous bathymetry of El Malecon, Española, and Floreana rookeries would allow the animals therein to access both, epipelagic prey over the shelf, and deep‐sea prey out of the shelf; this would lead to a higher prey richness and diet variability there. These findings provide evidence of GSL adopting a trophic flexibility to tune their diets to different ecological contexts. This strategy would be crucial for this endangered species to overcome the challenges faced in a habitat with fluctuating foraging conditions. [ABSTRACT FROM AUTHOR]

Posterior reversible encephalopathy syndrome (PRES) is a rare neurological complication of allogeneic stem cell transplantation (incidence of 1.1-22%). Usually presents as a disorder of consciousness or encephalopathy, associated in most cases with headache, visual disturbance, Hypertension and epileptic seizures. Literature describes the presence of PRES in patients who have received immunosuppressive agents after Hematopoietic Stem Cells transplantation, including cyclosporine, tacrolimus, and sirolimus, as well as chemotherapy such as cyclophosphamide, vincristine, methotrexate, L-aspar, among others. Two cases of hematological patients with PRES are presented, and a review of the literature on PRES after Hematopoietic Stem Cells transplantation. [ABSTRACT FROM AUTHOR]