Explore the vast range of titles available.

Cat-transmitted sporotrichosis caused by Sporothrix brasiliensis is an emerging zoonosis in Latin America. Because treatment of feline sporotrichosis is often not effective, we sought to determine whether treatment failure results from S. brasiliensis strains that have existing elevated MICs for itraconazole, the primary treatment for this disease. During 2021-2023 at the triple border region of Brazil, Paraguay, and Argentina, 108 S. brasiliensis strains were isolated from felines before antifungal treatment. The main clinical manifestation was cutaneous disseminated sporotrichosis (61%), which was the only form resulting in sporotrichosis-induced deaths (61%). We conducted antifungal susceptibility testing for 9 antifungal compounds, evaluating for both mycelial and yeast phases. MIC levels were low for most antifungal agents but were higher in the mycelial phase than in the yeast phase, especially for voriconazole and isavuconazole. We conclude that the varying clinical manifestations of sporotrichosis and large differences in mortality rates were not caused by elevated itraconazole MICs.

Megalodoras uranoscopus (Eigenmann & Eigenmann) (Siluriformes, Doradidae) (the giant-talking catfish or the giant-raphael catfish), from the Peruvian Amazon, hosts a new species of Cosmetocleithrum described herein as Cosmetocleithrum falsunilatum sp. n. The male copulatory organ of the new species closely resembles that of Unilatus spp. – with multiple tight loops and non-articulated accessory piece - which reveals its morphological uniqueness among members of Cosmetocleithrum. A phylogenetic analysis using 28S rDNA of available sequences suggests that Cosmetocleithrum is composed by two basal clades, one of them composed by sequences of the new species and C. trachydorasi.

Sporothrix brasiliensis is an emerging fungal pathogen causing cat-transmitted sporotrichosis, an epi-zoonosis affecting humans, cats and dogs in Brazil and now spreading to neighboring South American countries. Here, we report the first two autochthonous cases of cat-transmitted sporotrichosis in Paraguay. The first case was a four-year-old male cat showing several ulcerative lesions, nasal deformity and respiratory symptoms. The second case was a one-year-old male cat showing a single ulcerated lesion, respiratory symptoms and nasal deformity. Both cases were admitted to a veterinary clinic in Ciudad del Este, Paraguay. Isolates were recovered from swabs of the two cases. Using molecular methods, the isolates were identified as S. brasiliensis.

The family Epibryaceae is one of the early-diverging lineages within the order Chaetothyriales . Available molecular data show that most species are associated with mosses, liverworts, and lichens, typically inhabiting apparently psychrophilic environments. However, genomic information about this family remains scarce. This study presents whole-genome sequencing of six reference strains from the genus Epibryon ( Chaetothyriales , Epibryaceae ), aiming to elucidate their ecological adaptations and evolutionary relationships. Comparative analyses of CAZymes and MEROPS annotations showed that most members of Epibryaceae have a reduced set of enzymes associated with lignin degradation. Additionally, the presence of the CspA protein, linked to freezing tolerance, and the absence of the ClpA/B enzyme, associated with heat stress tolerance, suggest a strong preference for cold environments compared with other Chaetothyriales lineages. Multilocus phylogenetic analyses clarified species boundaries and resulted in the introduction of Epibryon brunneolum comb. nov. within the family. Based on phylogenetic analysis, ecological data regarding the preferred habitat of the family, and the presence of exclusive enzymes associated with extreme cold environments, the results indicate that this family is distinct from other chaetothyrialean fungi.

Estuarine chaetognath population dynamics are poorly known worldwide. We have conducted eight seasonal campaigns (October 2007–August 2008) sampling three sectors in the subtropical Babitonga Bay estuary (26°S 48°W) in order to depict chaetognath abundance and population structure dynamics and test the influence of hydrography and food availability and type. Of three species sampled, Parasagitta friderici represented >93% of abundance in all samples and was examined in detail. There were no differences in P. friderici abundance between the sectors of the estuary, related to its high tolerance to low salinity, a feature not common for most chaetognath species. Salinity tolerance is an important adaptive characteristic to thrive within estuarine systems, and probably is responsible for the dominance of P. friderici in coastal and brackish water environments throughout most of its distribution. Juveniles dominated the population most of the year, except in February–April when abundances were lower and adults predominated. These results suggest that recruitment occurs continuously throughout the year, being more intense between October and January (spring to early summer) and in May (autumn) when densities and proportion of juveniles were higher. General Additive Models suggest that temperature and zooplankton biomass are significant (P < 0.05) factors influencing juvenile abundance while only the latter influenced the adults. We conclude that food availability is the most important driver in the studied population of P. friderici and recruitment peaks, which lead to high densities, seem to occur following peaks of their copepod prey along with particular temperature conditions (22–23°C).

This study aimed to enhance our understanding in monogenoid evolution by using morphological and molecular data to determine kinship relationships between species and changes in morphological structures over time. We focused on variations in characteristics among the organisms of the family Gyrodactylidae, concentrating on the phylogenetic position of Polyclithrum with other genera in the family. We collected specimens of Polyclithrum from the striped mullet, Mugil cephalus and Swingleus, and Fundulotrema specimens from mummichog Fundulus heteroclitus in estuarine systems of South Carolina, United States. In addition, we analyzed them and other genera (including e.g., Mormyrogyrodactylus, Gyrodactyloides, and Macrogyrodactylus) using both morphological and molecular (18S rDNA) approaches. We performed phylogenetic trees based on Maximum Parsymony, Maximum Likelihood and Bayesian Inference, and constructed a character morphological matrix by Parsimony Reconstruction of Ancestral Character States method. Our results suggest a homoplastic origin with evolutionary convergences in characters, revealing that there is inconsistency between our data and previously published works based solely on morphological structures of the group. The homoplasy scenario found in Gyrodactylidae can be a result of the limited set of putative homologous morphological features. However, differences between the phylogenies based on morphology and those based on molecular data may arise from both databases. While morphology remains essential in understanding the evolution of this group, molecular data, otherwise, provide a less biased source of information for constructing phylogenetic hypotheses. Combining these data facilitates a better comprehension of the homologous status of morphological features and to understand Gyrodactylidae evolutionary history.

1. Because host–parasite interactions are so ubiquitous, it is of primary interest for ecologists to understand the factors that generate, maintain and constrain these associations. Phylogenetic comparative studies have found abundant evidence for host-switching to relatively unrelated hosts, sometimes related to diversification events, in a variety of host–parasite systems. For Monogenoidea (Platyhelminthes) parasites, it has been suggested that the co-speciation model alone cannot explain host occurrences, hence host-switching and/or non-vicariant modes of speciation should be associated with the origins and diversification of several monogenoid taxa. 2. The factors that shape broad patterns of parasite sharing were investigated using path analysis as a way to generate hypotheses about the origins of host–parasite interactions between monogenoid gill parasites and Neotropical freshwater fishes. 3. Parasite sharing was assessed from an interaction matrix, and explanatory variables included phylogenetic relationships, environmental preferences, biological traits and geographic distribution for each host species. 4. Although geographic distribution of hosts and host ecology are important factors to understand host–parasite interactions, especially within host lineages that share a relatively recent evolutionary history, phylogeny had the strongest overall direct effect on parasite sharing. 5. Phylogenetic contiguity of host communities may allow a 'stepping-stone' mode of host-switching, which increases parasite sharing. Our results reinforce the importance of including evolutionary history in the study of ecological associations, including emerging infectious diseases risk assessment.

The study of biological invasions can be roughly divided into three parts: detection, monitoring, mitigation. Here, our objectives were to describe the marine fauna of the area of the port of São Sebastião (on the northern coast of the state of São Paulo, in the São Sebastião Channel, SSC) to detect introduced species. Descriptions of the faunal community of the SSC with respect to native and allochthonous (invasive or potentially so) diversity are lacking for all invertebrate groups. Sampling was carried out by specialists within each taxonomic group, in December 2009, following the protocol of the Rapid Assessment Survey (RAS) in three areas with artificial structures as substrates. A total of 142 species were identified (61 native, 15 introduced, 62 cryptogenic, 4 not classified), of which 17 were Polychaeta (12, 1, 1, 3), 24 Ascidiacea (3, 6, 15, 0), 36 Bryozoa (17, 0, 18, 1), 27 Cnidaria (2, 1, 24, 0), 20 Crustacea (11, 4, 5, 0), 2 Entoprocta (native), 16 Mollusca (13, 3, 0, 0). Twelve species are new occurrences for the SSC. Among the introduced taxa, two are new for coastal Brazil. Estimates of introduced taxa are conservative as the results of molecular studies suggest that some species previously considered cryptogenic are indeed introduced. We emphasize that the large number of cryptogenic species illustrates the need for a long-term monitoring program, especially in areas most susceptible to bioinvasion. We conclude that rapid assessment studies, even in relatively wellknown regions, can be very useful for the detection of introduced species and we recommend that they be carried out on a larger scale in all ports with heavy ship traffic.

Pimelodus , the most diverse genus of Pimelodidae, has a complex taxonomic history. Various species occur in the Paraná River Basin of South America, with some, including P. maculatus and P. platicirris , in sympatry. Pimelodus maculatus is widely distributed in this watershed, whereas P. platicirris is poorly known and cited for only a few locations in the Upper Paraná River Basin. The taxonomic status of P. platicirris has been the subject of discussion due to insufficient diagnosis and the sharing of apomorphic characters with other species. We tested for morphometric and genetic differentiation between non-topotype fishes identified as P. maculatus and P. platicirris based on color pattern. We sampled 16 individuals of each species in the Araguari River, Upper Paraná River Basin, and analyzed them for 29 morphometrical characters, DNA barcoding and 13,581 nuclear SNPs. Morphometrical analysis indicated no differences between the two species. Similarly, mitochondrial DNA analysis, which included sequences of topotype individuals of P. maculatus available online, supported all P. platicirris individuals as belonging to the P. maculatus lineage from the Upper and Lower Paraná River basins, without nuclear genetic differentiation. These results indicate that the non-topotype individuals identified as P. platicirris based on color pattern are indeed P. maculatus . Consequently, the diagnostic characters usually attributed to delimiting P. platicirris are instead part of the wide morphological and color pattern variation of P. maculatus . The taxonomy of P. platicirris merits special attention due to the possibility of synonymy with P. maculatus . Enhancing the understanding of Pimelodus biodiversity in the Paraná River Basin is key for the development of conservation programs specifically designed for its species.

Species of Monogenoidea (Platyhelminthes) are in its majority ectoparasites of marine and freshwater fishes. Many species of the group can promote great economic losses to fish production systems worldwide. The present study describes a new species, Gyrodactylus lilianae n. sp., from the body surface, fins and barbels of a captive South American catfish, Rhamdia quelen (Quoy & Gaimard) (Siluriformes: Heptapteridae) from southern Brazil. The new species is morphologically similar to Neotropical species of Gyrodactylus von Nordmann, 1832 from Siluriformes from which it differs most conspicuously by the morphology of the hook with a pronounced convex heel, somewhat depressed, slightly pointed toe, and a small distal bulb. The identity of the new species is also strongly supported by phylogenetic analysis based on cytochrome c oxidase subunit 2 mitochondrial gene (cox2) sequences and the rDNA fragment ITS1-5.8-ITS2. Infections with the new species in captive R. quelen juveniles were considered the main causative agent of observed mortalities. Tissue damage caused by G. lilianae n. sp. apparently facilitated the occurrence of secondary infections by protists (Ichthyophthirius multifiliis) and bacteria (Aeromonas hydrophila).