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Rising global temperatures are expected to reshape predator–prey interactions, which are central to the structure, dynamics and functioning of natural ecosystems. While predator feeding rates are known to depend on temperature and vary across species, how this relationship varies within species across the different climatic regions conditions they inhabit is still poorly understood. Yet identifying this relationship is essential to predict how natural populations and communities will be affected by climate change across different geographic and climatic regions. Here we address this knowledge gap by experimentally measuring the thermal responses of predators collected from nine populations representing three latitudes spanning most of the continental US (a gradient of 11°). Specifically, we set up 145 independent replicated predator–prey systems across an experimental temperature gradient ranging from 5–35°C to quantify the thermal response curves for each of the nine predator populations. We found stark differences in thermal responses across latitudes ranging from clear humped‐shaped curves to a mostly linear increase. Most notably, these intraspecific differences in the overall shapes of thermal responses reveal opposing latitudinal patterns depending on the range of temperature considered. These results reveal that local climate can shape how interactions respond to warming and highlight the need to consider past local climatic conditions when predicting responses of natural systems to climate change at the local, regional, and global scale. [ABSTRACT FROM AUTHOR]

Polymorphic yeasts can switch between unicellular division and multicellular filamentous growth. Although prevalent in aquatic ecosystems, such as the open ocean, we have a limited understanding of the controlling factors on their morphological variation in an aquatic ecology context. Here we show that substrate concentration regulates cell morphogenesis in a cosmopolitan polymorphic yeast, Aureobasidium pullulans, isolated from the pelagic open ocean and analyzed in liquid batch culture. Filamentous cell development was triggered only under high initial substrate conditions, suggesting that hyphal growth could be more advantageous under eutrophic conditions and may influence pelagic fungal interactions with particulate organic matter. Filamentous growth proportionally declined before the exhaustion of substrate and before budding yeast-type cell division entered stationary phase, possibly modulated by quorum sensing as previously evidenced in other polymorphic yeasts. We also found that budding yeast-type unicells decreased in size and became more elongated in shape in response to substrate depletion, resulting in higher cell surface area to volume ratios, which could affect yeast dispersal and/or provide a nutrient uptake advantage under oligotrophic conditions. Our results demonstrate resource-responsive morphological plasticity in a marine-derived polymorphic yeast, providing mechanistic insight into the ability of fungi to survive fluctuating environmental conditions such as in the open ocean. [ABSTRACT FROM AUTHOR]

The impact of artificial intelligence (AI) in biotechnology has become increasingly significant, driving advancements across multiple subfields in several areas of science. The demand for faster data analysis, integration of extensive databases, pattern recognition, problem solving, and even hypothesis generation has fueled the development of AI technologies in subjects like modern biotechnology, which AI has revolutionized, where the main goal is to develop new advanced products and technologies through the manipulation of biological organisms. The main impacts of AI observed in biotechnology are focused on four colors of biotechnology: green (agricultural sector); red (health sector); white (industries); and blue (marine sector). Numerous AI tools have been developed and made freely available, significantly reducing researchers' workloads. However, the application of AI in biotechnology also raises questions that must be addressed. This review exhibits and discusses the impacts of AI on biotechnology, the advantages and disadvantages of its current presence, and the potential ethical issues and social impacts. [ABSTRACT FROM AUTHOR]

Early detection of submerged bodies is essential to increase the possibility of recovery. Different water bodies present different challenges, particularly rivers and the ocean, where chances of detection are vastly reduced. Modern recreational fish finders incorporate multiple sonar technologies, including Sidescan sonar, at high‐frequency resolutions, similar to commercial units. Recreational units are widely available and usually hull‐mounted, allowing them to be utilized on almost any vessel in shallow and difficult to navigate environments. Recreational fish finders are currently an untapped resource which may assist search teams with the early detection and recovery of human remains submerged in shallow water (<20 m). This research investigated the efficacy of a modern recreational fish finder attached to a kayak to detect human proxies and living human volunteers submerged at shallow depths in (1) two indoor freshwater environments and (2) two outdoor environments (a freshwater lake and a nearshore coastal environment). Results demonstrated that recreational fish finders can detect human bodies submerged in both fresh and saltwater contexts at shallow depths within the water column and on the water bottom. Recreational units equipped with Sidescan sonar (800 kHz) provided the necessary resolution for underwater body detection at shallow depths. These sophisticated sensors are currently used by recreational boaters and anglers, and offer the opportunity to increase the eyes in the water not just by search and recovery teams, but by the public itself. [ABSTRACT FROM AUTHOR]

The application of environmental DNA (eDNA) methods to simultaneously study vertebrate diversity holds promise to accelerate conservation efforts, especially in freshwater systems which are among the most imperiled in the world. Here, using eDNA sampling, we identify patterns of vertebrate biodiversity across different habitats of the Kankakee River watershed, one of the most diverse lotic systems in Illinois, USA. Our eDNA metabarcoding analyses identified 147 different taxa, including 77 fishes, 38 birds, 24 mammals, five amphibians and three reptiles at 11 locations in the watershed, including tributaries and mainstem stretches upstream and within the Kankakee River State Park protected area. When compared to seining, eDNA sampling consistently detected more fish species, including non-native and imperiled species. We also found that vertebrate communities among the different habitats significantly varied in taxonomic composition, showing an upstream-downstream shift along the mainstem river as well as tributary-specific assemblages. Our study demonstrates the ability of single-marker eDNA metabarcoding to simultaneously document aquatic and terrestrial communities across large temperate lotic ecosystems and to monitor diversity patterns across protected areas. [ABSTRACT FROM AUTHOR]

Aim: Species presence–absence data can be time‐consuming and logistically difficult to obtain across large spatial extents. Yet these data are important for ensuring changes in species distributions are accurately monitored and are vital for ensuring appropriate conservation actions are undertaken. Here, we demonstrate how environmental DNA (eDNA) sampling can be used to systematically collect species occupancy data rapidly and efficiently across vast spatial domains to improve understanding of factors influencing species distributions. Location: South‐eastern Australia. Methods: We use a widely distributed, but near‐threatened species, the platypus (Ornithorhynchus anatinus), as a test case and undertake an environmentally stratified systematic survey to assess the presence–absence of platypus eDNA at 504 sites across 584,292 km2 of south‐eastern Australia, representing ~37% of the species' extensive distribution. Site occupancy‐detection models were used to analyse how landscape‐ and site‐level factors affect platypus occupancy, enabling us to incorporate uncertainty at the different levels inherent in eDNA sampling (site, water sample replicate and qPCR replicate). Results: Platypus eDNA was detected at 272 sites (~54%) with platypuses more likely to occupy sites in catchments with increased runoff and less zero‐flow days, and sites with access to banks suitable for burrowing. Platypuses were less likely to occupy sites in catchments with a high proportion of shrubs and grasslands, or agricultural land use. Main Conclusions: These data provide an important large‐scale validation of the landscape‐ and site‐level factors influencing platypus occupancy that can be used to inform future conservation efforts. Our case study shows that systematically designed, stratified eDNA surveys provide an efficient means to understand how environmental characteristics affect species occupancy across broad environmental gradients. The methods employed here can be applied to aquatic and semi‐aquatic species globally, providing unprecedented opportunities to understand biodiversity status and change and provide insights for current and future conservation actions. [ABSTRACT FROM AUTHOR]

To describe the incidence, severity, burden and sport specific characteristics of injuries reported in elite diving athletes. Descriptive epidemiology study. Medical attention and time-loss injuries from 63 (43 female, 20 male) Australian national diving programme athletes were prospectively collected over four seasons (September 2018–August 2022). Injury incidence rates and burden were calculated, standardised per 365 athlete days, and compared across groups using negative binomial generalised linear models. In total 421 injuries were reported (female = 292, male = 129) at an injury incidence rate of 2.36 (95 % confidence interval = 2.14–2.60) per 365 athlete days. Annual injury prevalence ranged from 70.0 to 85.1 %. Approximately two-thirds of injuries (67.2 %) resulted in a period of time-loss. The overall injury burden was 91 days of absence (95 % confidence interval = 81–102) per 365 athlete days. Stress fractures in springboard diving athletes incurred the largest mean days of time-loss compared to other injured tissue types. The majority of injuries were reported to occur during training (79.3 %) as opposed to competition (2.4 %), with more than half (55.3 %) of all reported injuries occurring during pool training sessions. Water entry (30.4 %) or take-off (27.8 %) were the most frequently reported mechanism of injury. Annual injury prevalence reported in competitive Australian diving athletes was found to be high. Contrary to existing literature, competitive diving injuries were reported to occur within the daily training environment, with few injuries occurring during competition. Notable injury differences between springboard and platform athletes were observed. [ABSTRACT FROM AUTHOR]

The effect of adding two different humic acid hydrogel on the quality of low starch floating aquatic extruded pellet feed was studied, such as extruded feed bulk density, dissolution rate, softening time, pellet feed durability index (PDI), hardness, expansion rate and viscoelasticity. A total of 8 experimental groups were set up, which were: NCon group (negative control group): for the typical low starch formula (starch content of 8%) of the basic mixture; PCon group (positive control group) : to add high gluten flour in the base material, MS0.2, MS0.4 and MS0.6 groups: to add 0.2%, 0.4%, 0.6% wood-stone gem humic acid hydrogel in the base material; XD0.2, XD0.4 and XD0.6 groups: for adding 0.2%, 0.4%, 0.6% new energetic humic acid hydrogel into the base mixture. The results showed that: ① compared with NCon group, the volume weight of PCon group was significantly decreased and the bulking rate was significantly increased (P<0.05). ②Compared with NCon group, the feed hardness and viscoelasticity of MS0.2 and MS0.4 groups were significantly increased (P<0.05), and the softening time of MS0.2 group was significantly increased (P<0.05), in the groups of MS0.2, MS0.4 and MS0.6, the dissolution rate and bulk density were significantly decreased and the expansion rate was significantly increased (P<0.05), while in the groups of XD0.2, XD0.4 and XD0.6, the expansion rate, hardness and softening time were significantly increased, the viscoelasticity and dissolution rate decreased significantly (P<0.05). ③ Compared with PCon group, the expansion rate of MS0.2 group was significantly increased (P<0.05), the viscoelasticity and hardness of MS0.2 and MS0.4 groups were significantly decreased (P<0.05), and the volume weight of MS0.6 group was significantly decreased (P<0.05), PDI was significantly increased in MS0.2, MS0.6 groups (P<0.05), dissolution rate was significantly decreased in MS0.2, MS0.4, MS0.6 groups (P<0.05), feed bulk density, hardness and softening time were significantly increased in XD0.2, XD0.4, XD0.6 groups, the dissolution rate and viscoelasticity were significantly decreased (P<0.05), the expansion rate was significantly decreased (P<0.05) in XD0.4 group, and the PDI was significantly increased (P<0.05) in XD0.6 group. In general, humic acid gel was better than high gluten flour, and the product quality of wood stone gem group was better than that of NDA group. The study provided data support for the application of humic acid gel in the production practice of low starch floating aquatic expanded pellet feed. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the supplementation of the probiotic Pseudoalteromonas piscicida 1Ub to the biofloc system as an ecofriendly strategy for protecting white shrimp (Penaeus vannamei) from Vibrio parahaemolyticus infection. Shrimp with an average body weight of (0.50 ± 0.09) g were reared in 30 glass jars with a working volume of 2.5 L at a density of 20 ind/L. Shrimp were reared for 5 d for each treatment, which included the biofloc system without and with 106 colony forming unit (CFU) per mL probiotic. The regular clear water system was used as control. All treatment groups were challenged with 103, 105, and 107 CFU/mL V. parahaemolyticus. For the negative control, shrimp were reared without V. parahaemolyticus. The results showed that the density of V. parahaemolyticus cocultured with P. piscicida 1Ub decreased and the density of V. parahaemolyticus in rearing water and shrimp body in the probiotic-treated group was lower than that in the control group (P < 0.05). The survival and immune response (total hemocyte count, phagocytic activity, respiratory burst, phenoloxidase, and superoxide dismutase) of shrimp in the probiotic group was higher than that in the positive control (P < 0.05). Moreover, supplementing the biofloc system with the probiotic could protect shrimp hepatopancreas from damage caused by V. parahaemolyticus, regardless of bacterial density. Thus, the supplementation of the probiotic P. piscicida 1Ub in the biofloc system could significantly protect and increase the resistance of shrimp to V. parahaemolyticus infection. [ABSTRACT FROM AUTHOR]

Streams and river ecosystems contribute to global carbon cycle via collecting, storing, transforming and producing organic matter. The general paradigm is that most stream ecosystems are heterotrophic, respiring more carbon than they produce, nonetheless, many streams are autotrophic for some time, and a few may autotrophic on an annual scale. Periodic autotrophy is associated with high light, low disturbance, and low watershed carbon inputs, but limited examples of annual-scale autotrophy make it difficult to estimate how frequently net autotrophy occurs and what drives this net storage or export of carbon. Here, we use a spatially and temporally extensive dataset of 236 rivers across the continental USA with 921 years of daily metabolism data to assess the scale of annual and seasonal autotrophy and estimate its strongest covariates. Only 6% of rivers in this dataset were consistently autotrophic on an annual timescale, but 67% of rivers experienced at least one autotrophic event lasting longer than 7 days. These periodic autotrophic events frequently began in spring and summer. By comparing the 37 annually autotrophic rivers identified in our dataset to examples in the literature, we found that anthropogenically driven autotrophy arising from agricultural and urban land use is underrepresented in the study of riverine metabolism. We used quantile regression models to test hypothesized drivers of autotrophy and a sparse lasso technique to broadly explore a range of 86 watershed and in-stream covariates. Our models support previous findings that high light, long periods between disturbances, and low terrestrial production covary with more autotrophy. Additionally, through sparse regression, we found that elevation and river width may be useful synthesis variables that explain the distribution of autotrophic rivers. [ABSTRACT FROM AUTHOR]

Heavy metals, which include lead (Pb), mercury (Hg), cadmium (Cd), chromium (Cr), arsenic (As), nickel (Ni)and zinc (Zn), serve as persistent environmental pollutants that pose significant risks to aquatic ecosystems and human health. This review article provides a comprehensive analysis of the toxicological effects of heavy metals on fish, underscoring the pathways of exposure, biological implications, and methodologies for mitigating toxicity. We examine the sources of heavy metal contamination, such as industrial discharges, agricultural runoff, domestic sewage, and mining activities, which contribute to the accumulation of these deleterious substances in aquatic environments. The review clarifies the processes through which heavy metals penetrate fish tissues and the resulting physiological and biochemical alterations, including bioaccumulation, toxicity, oxidative stress, growth inhibition, and behavioral changes. The manuscript details various analytical methodologies employed to detect and quantify heavy metals in fish tissues, while also addressing the difficulties associated with monitoring and assessing contamination levels. Moreover, we evaluate the ecological consequences of heavy metal accumulation in fish populations and the potential risks posed to human health through the consumption of contaminated fish products. The review further considers recent innovations in bioremediation techniques, such as the use of microbial and phytoremediation systems, aimed at alleviating heavy metal pollution in aquatic environments. By synthesizing existing research findings and identifying areas where knowledge is lacking, this review seeks to provide a valuable resource for researchers, policymakers, and environmental advocates. It underscores the necessity for continuous monitoring, more rigorous regulatory frameworks, and novel remediation strategies to address the on-going challenge of heavy metal toxicity in fish, thereby safeguarding both aquatic ecosystems and public health. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the supplementation of the probiotic Pseudoalteromonas piscicida 1Ub to the biofloc system as an ecofriendly strategy for protecting white shrimp (Penaeus vannamei) from Vibrio parahaemolyticus infection. Shrimp with an average body weight of (0.50 ± 0.09) g were reared in 30 glass jars with a working volume of 2.5 L at a density of 20 ind/L. Shrimp were reared for 5 d for each treatment, which included the biofloc system without and with 106 colony forming unit (CFU) per mL probiotic. The regular clear water system was used as control. All treatment groups were challenged with 103, 105, and 107 CFU/mL V. parahaemolyticus. For the negative control, shrimp were reared without V. parahaemolyticus. The results showed that the density of V. parahaemolyticus cocultured with P. piscicida 1Ub decreased and the density of V. parahaemolyticus in rearing water and shrimp body in the probiotic-treated group was lower than that in the control group (P

Production of synthetic plastic obtained from fossil fuels are considered as a constantly growing problem and lack in the management of plastic waste has led to severe microplastic pollution in the aquatic ecosystem. Plastic particles less than 5mm are termed as microplastics (MPs), these are pervasive in water and soil, it can also withstand longer period of time with high durability. It can be broken down into smaller particles and can be adsorbed by various life-forms. Most marine organisms tend to consume plastic debris that can be accumulated easily into the vertebrates, invertebrates and planktonic entities. Often these plastic particles surpass the food chain, resulting in the damage of various organs and inhibiting the uptake of food due to the accumulation of microplastics. In this review, the physical and chemical properties of microplastics, as well as their effects on the environment and toxicity of their chemical constituents are discussed. In addition, the paper also sheds light on the potential of microorganisms such as bacteria, fungi, and algae which play a pivotal role in the process of microplastics degradation. The mechanism of microbial degradation, the factors that affect degradation, and the current advancements in genetic and metabolic engineering of microbes to promote degradation are also summarized. The paper also provides information on the bacterial, algal and fungal degradation mechanism including the possible enzymes involved in microplastic degradation. It also investigates the difficulties, limitations, and potential developments that may occur in the field of microbial microplastic degradation. [ABSTRACT FROM AUTHOR]

Skin microbiomes provide vital functions, yet knowledge about the drivers and processes structuring their species assemblages is limited—especially for non‐model organisms. In this study, fish skin microbiome was assessed by high throughput sequencing of amplicon sequence variants from metabarcoding of V3–V4 regions in the 16S rRNA gene on fish hosts subjected to the following experimental manipulations: (i) translocation between fresh and brackish water habitats to investigate the role of environment; (ii) treatment with an antibacterial disinfectant to reboot the microbiome and investigate community assembly and priority effects; and (iii) maintained alone or in pairs to study the role of social environment and inter‐host dispersal of microbes. The results revealed that fish skin microbiomes harbour a highly dynamic microbial composition that was distinct from bacterioplankton communities in the ambient water. Microbiome composition first diverged as an effect of translocation to either the brackish or freshwater habitat. When the freshwater individuals were translocated back to brackish water, their microbiome composition converged towards the fish microbiomes in the brackish habitat. In summary, external environmental conditions and individual‐specific factors jointly determined the community composition dynamics, whereas inter‐host dispersal had negligible effects. The dynamics of the microbiome composition was seemingly non‐affected by reboot treatment, pointing towards high resilience to disturbance. The results emphasised the role of inter‐individual variability for the unexplained variation found in many host‐microbiome systems, although the mechanistic underpinnings remain to be identified. [ABSTRACT FROM AUTHOR]

Aquatic birds are notable among the global avifauna for living in environments exposed to large amounts of light. Despite growing evidence that visual adaptations to light underly the ecology and evolution of the avian tree of life, no comprehensive comparative analysis of visual acuity as approximated by eyes size exists for the global aquatic avifauna.Here, I use Stanley Ritland's unpublished dataset of measurements for axial length collected from museum specimens to explore the ecology and evolution of eye size variation for half of the aquatic avifauna (N = 464 species).After correcting for body mass allometry and incorporating phylogenetic relationships, aquatic species had significantly smaller eyes compared to terrestrial species. Furthermore, species using hyperopic foraging manoeuvres, exhibiting carnivorous and insectivorous diets, and displaying nocturnal behaviour had larger eyes. Plunge‐divers (e.g. boobies and tropic birds) and stalkers (e.g. herons) had the largest relative eye sizes, especially species identifying prey at higher altitudes or longer distances. Underwater pursuit‐divers foraging at greater depths had larger eyes, likely due to the dramatic attenuation of light in the deep ocean. Overall, residual eye size was phylogenetically conserved (l = 0.94), with phylogeny alone explaining 62% of residual eye size variation.Collectively, these results suggest that the relatively bright environments found in aquatic ecosystems negate the adaptive benefits of costly metabolic investments associated with developing and maintaining larger eyes, while also reducing the potential occurrence of disability glare. Strong correlations between eye size and foraging ecology in different aquatic environments corroborate similar comparative studies of terrestrial birds and underscore the central role that vision has played in driving the ecology and evolution of the global avifauna. [ABSTRACT FROM AUTHOR]

The Microsporidia, an often overlooked fungal lineage, exhibit increasing diversity and taxonomic understanding with the use of genomic techniques. They are obligate parasites infecting a diversity of hosts, including crustaceans. Crustacea are, in essence, ancient insects and their relationship with the Microsporidia is both diverse and convoluted. Relationships between crayfish and their microsporidian parasites display geospatial and taxonomic diversity. Through classical (histological, ultrastructural, developmental) and genomic (phylogenetic, phylogenomic) approaches, we expand the known diversity of crayfish-infecting microsporidia into the genus Nosema by describing three novel species from North America: Nosema astafloridana n. sp. infecting Procambarus pictus and Procambarus spiculifer, Nosema rusticus n. sp. infecting Faxonius rusticus, and Nosema wisconsinii n. sp. infecting Faxonius propinquus and Faxonius virilis. Additionally, we provide SSU sequence data for further Nosema diversity from Procambarus clarkii and Pacifasticus gambelii. The taxonomy of aquatic crustacean-infecting Nosema have been under scrutiny among microsporidiologists—using genomic data we solidify this systematic relationship. Our genomic data reveal phylogenomic divergence between terrestrial insect-infecting Nosema and aquatic crustacean-infecting Nosema but place our novel species within the Nosema. Comparative genomic analysis reveal that Nosema rusticus n. sp. is a tetraploid organism, making this the first known polyploid from the genus Nosema. Annotation of the genomic data highlight that crayfish-infecting Nosema have distinct proteomic differences when compared to amphipod and insect-infecting microsporidians. Alongside the new diversity uncovered and genome-supported systematics, we consider the role of these new 'invasive' parasites in biological invasion systems, exploring their relationship with their invasive hosts. [ABSTRACT FROM AUTHOR]

Food agencies recommend increasing the consumption of aquatic food to promote healthy living and sustainability, and, particularly, to prevent Western lifestyle-related diseases and secure sustainable food systems. This requires growth in global seafood production, and the utilization of low trophic species (LTS) is suggested. LTS are already considered nutritious and important in Asian and Pacific diets. As the use of LTS is expanding in Western diets, producers and consumers need information on the food safety practices associated with them and their nutritional content. LTS are mainly immobile or slow-moving extractive species or organisms that feed on such, and their nutrient and contaminant content varies by species and location. Species-specific knowledge on nutritional contents and safe consumption limits is often missing, making the monitoring and analysis of contaminants, nutrients, and consumption data crucial to guiding the utilization and consumption of LTS. Using global and regional standards regarding nutrients, food hazards, and labeling, this review highlights the appropriate guidelines and regulations for guiding the utilization of selected novel species and also identifies knowledge gaps. [ABSTRACT FROM AUTHOR]

The rapid loss of biodiversity in freshwater systems asks for a robust and spatially explicit understanding of species' occurrences. As two complementing approaches, habitat suitability models provide information about species' potential occurrence, while environmental DNA (eDNA) based assessments provide indication of species' actual occurrence. Individually, both approaches are used in ecological studies to characterize biodiversity, yet they are rarely combined. Here, we integrated high‐resolution habitat suitability models with eDNA‐based assessments of aquatic invertebrates in riverine networks to understand their individual and combined capacity to inform on species' occurrence. We used eDNA sampling data from 172 river sites and combined the detection of taxa from three insect orders (Ephemeroptera, Plecoptera, Trichoptera; hereafter EPT) with suitable habitat predictions at a subcatchment level (2 km2). Overall, we find congruence of habitat suitability and eDNA‐based detections. Yet, the models predicted suitable habitats beyond the number of detections by eDNA sampling, congruent with the suitable niche being larger than the realized niche. For local mismatches, where eDNA detected a species but the habitat was not predicted suitable, we calculated the minimal distance to upstream suitable habitat patches, indicating possible sources of eDNA signals from upstream sites subsequently being transported along the water flow. We estimated a median distance of 1.06 km (range 0.2–42 km) of DNA transport based on upstream habitat suitability, and this distance was significantly smaller than expected by null model predictions. This estimated transport distance is in the range of previously reported values and allows extrapolations of transport distances across many taxa and riverine systems. Together, the combination of eDNA and habitat suitability models allows larger scale and spatially integrative inferences about biodiversity, ultimately needed for the management and protection of biodiversity. [ABSTRACT FROM AUTHOR]

Abstract Introduction Ankle sprains are the second most common sports injury after knee injuries, with about 85% of them affecting the lateral ankle ligaments. These injuries are particularly prevalent in sports like basketball and volleyball. Purpose To investigate the effect of Aquatic therapy as an early rehabilitation protocol for elite athletes with acute lateral ankle sprain grade III on back-to-sport time, dynamic balance, pain, Athletic performance, and muscle power compared to land-based exercise training. Methods Thirty elite athletes have ankle sprain grade III with sprain onset from 1 to 7 days, their age ranges from 18–30 years old were recruited. All participants are professional athletes; mainly participating in above-head sports such as volleyball and basketball. The patients were randomly allocated into two treatment groups: Group I (control group): 15 patients received a conventional physical therapy program of structured therapeutic exercise program, manual therapy and land-based exercises, in addition to external support, and Group II (Aquatic therapy group): 15 patients received aquatic training. Visual Analog Scale (VAS) was used to measure the pain intensity, while the dynamic balance was measured by the Star Excursion Balance Test. Athletic performance was measured by HOP Tests (Single, Triple, 6-m, and Cross-over hops) aided by the Agility T-Test (ATT) and Illinois Agility Test (IAT). Muscle power was tested by a Single Leg Press. Finally, back to sports time was recorded for each participant in both groups. Results There was a significant interaction effect of Aquatic therapy and time for VAS (p

Abstract: The retrieval algorithms used for optical remote sensing satellite data to estimate Earth's geophysical properties have specific requirements for spatial resolution, temporal revisit, spectral range and resolution, and instrument signal‐to‐noise ratio (SNR) performance to meet biogeoscience objectives. Studies to estimate surface properties from hyperspectral data use a range of algorithms sensitive to various sources of spectroscopic uncertainty, which are in turn influenced by mission architecture choices. Retrieval algorithms vary across scientific fields and may be more or less sensitive to mission architecture choices that affect spectral, spatial, or temporal resolutions and spectrometer SNR. We used representative remote sensing algorithms across terrestrial and aquatic study domains to inform aspects of mission design that are most important for impacting accuracy in each scientific area. We simulated the propagation of uncertainties in the retrieval process including the effects of different instrument configuration choices. We found that retrieval accuracy and information content degrade consistently at >10 nm spectral resolution, >30 m spatial resolution, and >8‐day revisit. In these studies, the noise reduction associated with lower spatial resolution improved accuracy vis à vis high spatial resolution measurements. The interplay between spatial resolution, temporal revisit, and SNR can be quantitatively assessed for imaging spectroscopy missions and used to identify key components of algorithm performance and mission observing criteria.

Introduction: Ankle sprains are the second most common sports injury after knee injuries, with about 85% of them affecting the lateral ankle ligaments. These injuries are particularly prevalent in sports like basketball and volleyball. Purpose: To investigate the effect of Aquatic therapy as an early rehabilitation protocol for elite athletes with acute lateral ankle sprain grade III on back-to-sport time, dynamic balance, pain, Athletic performance, and muscle power compared to land-based exercise training. Methods: Thirty elite athletes have ankle sprain grade III with sprain onset from 1 to 7 days, their age ranges from 18–30 years old were recruited. All participants are professional athletes; mainly participating in above-head sports such as volleyball and basketball. The patients were randomly allocated into two treatment groups: Group I (control group): 15 patients received a conventional physical therapy program of structured therapeutic exercise program, manual therapy and land-based exercises, in addition to external support, and Group II (Aquatic therapy group): 15 patients received aquatic training. Visual Analog Scale (VAS) was used to measure the pain intensity, while the dynamic balance was measured by the Star Excursion Balance Test. Athletic performance was measured by HOP Tests (Single, Triple, 6-m, and Cross-over hops) aided by the Agility T-Test (ATT) and Illinois Agility Test (IAT). Muscle power was tested by a Single Leg Press. Finally, back to sports time was recorded for each participant in both groups. Results: There was a significant interaction effect of Aquatic therapy and time for VAS (p < 0.001), single hop (p < 0.001), triple hop (p < 0.001), cross-over hop (p < 0.001), IAT (p = 0.019) and ATT (p < 0.001) of both affected and nonaffected. There was no significant interaction effect of Aquatic therapy and time for 6-MHT of affected (p = 0.923), and nonaffected (p = 0.140). There was a significant main effect of time for all dependent variables (p < 0.001) except for 6-MHT of affected (p = 0.939), nonaffected (p = 0.109), and IAT (p = 0.099). The Star excursion dynamic balance test (SEBT) and Single leg press revealed a significant difference between groups on affected and non-affected sides (p < 0.001*). Lastly and most importantly the back-to-sport time revealed a significant difference in the return-to-sport time in favor of the Aquatic therapy group who returned faster than the control group (p < 0.001*). Conclusion: Aquatic therapy is more effective than traditional protocols regarding early rehabilitation of acute ankle sprain grade III in Elite professional athletes for reducing pain intensity, improving dynamic balance and athletic performance and power and accelerating their return to sports time. Because aquatic therapy produces better outcomes, it is advised to be included in the rehabilitation programs of athletic patients with acute ankle sprains grade III. [ABSTRACT FROM AUTHOR]

The study determined acute toxicity, behavioural changes and histological effects of atrazine on juvenile Clarias gariepinus. The experiment involved exposing groups of fish to different concentrations {0.00 (control), 3.75, 6.25, 8.75, 11.25 and 13.75mg/l} of atrazine and monitoring fish mortality, physicochemical parameters of the test water and behavioural changes in the fish. The histological assessment of liver and gills was also carried out on dead fish to examine possible changes in their structural makeup in comparison to the organ extracted from the control. Acute toxicity test was conducted using standard methods and fish mortality was monitored for 96 hours. The physico-chemical parameters such as temperature, pH, dissolved oxygen, total dissolved solids and electrical conductivity in the test solutions were monitored using standard procedure. The study revealed that there was no mortality in the control group, which had no atrazine, while mortality rates increased with increasing concentrations of atrazine. The highest percentage mortality (83.33%) was recorded at the highest concentration of 13.75mg/l. The 96-hour lethal concentration (LC50) value of atrazine computed based on logarithm was 8.84mg/l. At exposure to acute concentrations, fish showed abnormal behaviour such as restlessness, loss of colouration, respiratory stress, erratic swimming and instant death. Histological effects observed on the gills exposed to atrazine included interstitial haemorrhage, deformed primary and secondary lamella, lesion, blanketing and blood congestion. Liver tissues showed necrosis and vacuolation of hepatocytes. Dissolved oxygen level in the test solutions that contained atrazine reduced drastically and this might have induced death in fish recorded in the study. Inference from the study revealed that atrazine may be toxic to aquatic organisms, particularly juvenile C. gariepinus. [ABSTRACT FROM AUTHOR]

Nano-phytoremediation is a novel green technique to remove toxic pollutants from the environment. In vitro regenerated Ceratophyllum demersum (L.) plants were exposed to different concentrations of chromium (Cr) and exposure times in the presence of titania nanoparticles (TiO2NPs). Response surface methodology was used for multiple statistical analyses like regression analysis and optimizing plots. The supplementation of NPs significantly impacted Cr in water and Cr removal (%), whereas NP × exposure time (T) statistically regulated all output parameters. The Firefly metaheuristic algorithm and the random forest (Firefly-RF) machine learning algorithms were coalesced to optimize hyperparameters, aiming to achieve the highest level of accuracy in predicted models. The R2 scores were recorded as 0.956 for Cr in water, 0.987 for Cr in the plant, 0.992 for bioconcentration factor (BCF), and 0.957 for Cr removal through the Firefly-RF model. The findings illustrated superior prediction performance from the random forest models when compared to the response surface methodology. The conclusion is drawn that metal-based nanoparticles (NPs) can effectively be utilized for nano-phytoremediation of heavy metals. This study has uncovered a promising outlook for the utilization of nanoparticles in nano-phytoremediation. This study is expected to pave the way for future research on the topic, facilitating further exploration of various nanoparticles and a thorough evaluation of their potential in aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Previous research has shown that exercise interventions requiring increased activation of the tibialis anterior (TA), the primary ankle dorsiflexor, can improve walking performance in individuals with foot drop. Correspondingly, heightened drag forces experienced during walking performed in water may augment TA activation during the swing phase of gait, potentially leading to improved walking gait on land. Therefore, this study aimed to compare surface electromyographic (sEMG) activation in the TA and medial gastrocnemius (GM) during gait performed in water versus on land. Thirty-eight healthy, recreationally active young adults, comprising 18 females and 20 males, participated in the study. Each participant completed 2 min walking trials under five conditions: land 2.5 mph, land 3.5 mph, water 2.5 mph, water 3.5 mph, and water 3.5 mph with added jet resistance. Stride kinematics were collected using 2-dimensional underwater motion capture. TA and GM, muscle activation magnitudes, were quantified using sEMG root-mean-square (RMS) amplitudes for both the swing and stance phases of walking. Additionally, TA and GM co-activation (Co-A) indices were estimated. Two-way within-subjects repeated measures analyses of variance were used to evaluate the main effects of and interactions between the environment and walking speed. Additionally, paired sample t-tests were conducted as a secondary analysis to investigate differences between walking in water at 3.5 mph with and without added jet resistance. Main effects and interactions were observed across various stride kinematics and sEMG measures. Notably, TA sEMG RMS during the swing phase of walking gait performed at 2.5 mph was 15% greater in water than on land (p < 0.001). This effect increased when walking gait was performed at 3.5 mph (94%; p < 0.001) and when jet resistance was added to the 3.5 mph condition (52%; p < 0.001). Furthermore, TA Co-A was increased during the stance phase of gait in water compared to on land (p < 0.001), while GM Co-A was reduced during the swing phase (p < 0.001). The findings of this study offer compelling evidence supporting the efficacy of aquatic treadmill walking as a potential treatment for individuals suffering from foot drop. However, further research is needed to evaluate whether a causal relationship exists between heightened TA activation observed during aquatic treadmill walking and improvements in voluntary dorsiflexion during gait. [ABSTRACT FROM AUTHOR]

Multispecies assemblages of Appalachian desmognathans have long intrigued ecologists seeking to understand the structure of ecological communities. Body size and life history in this group correlate with the moisture gradient from stream to forest, with large species being more aquatic and progressively smaller ones being ever more terrestrial. Since the work of N.G. Hairston, Sr. in the early 1980s, the prevailing hypothesis has been that predation and competition among desmognathans themselves have been the driving processes in the development and maintenance of the spatial organization along stream sides, with large, aggressive species forcing smaller ones to occupy less favorable terrestrial niches. Decades of research have confirmed that biotic interactions are important. However, evidence from recent studies has not agreed with the idea that biotic interactions are primary. Herein, I have concluded that the prevailing hypothesis fails to reconcile the currently available data. I have presented an alternative hypothesis that an abiotic factor, specifically the relative abundance of water, has been the primary force driving adaptation of species of Desmognathus longitudinally along moisture gradients by way of stream headwaters. Interspecific interactions, though important aspects of the current ecology of these species, are not the underlying drivers of spatial organization along the moisture gradient. I have further generated specific predictions that will enable this hypothesis to be tested. [ABSTRACT FROM AUTHOR]

Stenotrophomonas maltophilia is a gram-negative bacterium that can be routinely identified in the aquatic environment, and has become an emergent, multi-drug-resistant life-threatening organism in some circumstances. This bacterium was identified as a presumptive causative agent in cases of polysystemic granulomatous disease in one diamondback terrapin (Malaclemys terrapin) and one mata mata (Chelus fimbriata). Both chelonians presented with lethargy, hyporexia, and multifocal subcutaneous masses diagnosed by physical examination and in one individual on computed tomography (CT). The primary hematologic finding was moderate to severe heterophilic leukocytosis, and both turtles were treated with a combination of supportive care, systemic antibiotics, and/or surgical resection of subcutaneous masses. Medical and surgical management were unsuccessful, and one patient was euthanized and the other found deceased. Necropsies revealed multisystemic granulomas, and cultures identified growth of Stenotrophomonas maltophilia. A postmortem investigation into possible risk factors identified comorbidities including shell disease, repeated administration of injectable antibiotics, low environmental temperature, and aquatic pH changes as possible contributing factors. This bacterium appears to be an emerging organism of concern and should be considered as a potential cause of granulomas in aquatic chelonians. [ABSTRACT FROM AUTHOR]

Water hyacinth is an invasive aquatic weed that has significantly impacted the water bodies of Ethiopia's Rift-Valley since 1950s. This study investigates the past, present, and prospects of water hyacinth in the Koka and Dembel lakes, located in Ethiopia's Rift Valley. Field surveys and remote sensing techniques were employed to collect and analyze data spanning the past four decades and future projections. The study reveals that there was no water hyacinth coverage in Lake Dembel in 1994 and 2004 but dramatically increased to 2,966 hectares in 2014 to 4,210 hectares in 2024. Similarly, the converge in Koka increased from 1,378 hectares in 1994 to 4,199 hectares in 2024. By the year 2064, the weed will show area coverage increase of 767,443 and 56,692 hectares for Dembel and Koka respectively. The findings emphasize the urgent need for integrated management strategies to mitigate ecological and economic risks of water hyacinth in Ethiopia. [ABSTRACT FROM AUTHOR]

Pyrogenic carbon (PyC) is a significant component of the global soil carbon pool due to its longer environmental persistence than other soil organic matter components. Despite PyC's persistence in soil, recent work has indicated that it is susceptible to loss processes such as mineralization and leaching, with the significance and magnitude of these largely unknown at the hillslope and watershed scales. We present a review of the work concerning dissolved PyC transport in soil and freshwater. Our analysis found that the primary environmental controls on dissolved PyC (dPyC) transport are the formation conditions and quality of the PyC itself, with longer and higher temperature charring conditions leading to less transport of dPyC. While correlations between dPyC and dissolved organic carbon in rivers and other pools are frequently reported, the slope of these correlations was pool‐dependent (i.e., soil‐water, precipitation, lakes, streams, rivers), suggesting site‐specific environmental controls. However, the lack of consistency in analytical techniques and sample preparation remains a major challenge to quantifying environmental controls on dPyC fluxes. We propose that future research should focus on the following: (a) consistency in methodological approaches, (b) more quantitative measures of dPyC in pools and fluxes from soils to streams, (c) turnover times of dPyC in soils and aquatic systems, and (d) improved understanding of how mechanisms controlling the fate of dPyC in dynamic post‐fire landscapes interact. With more refined quantitative information about the controls on dPyC transport at the hillslope and landscape scale, we can increase the accuracy and utility of global carbon models. Key Points: Burn intensity of pyrogenic carbon (PyC) controls its dissolution and aqueous transportFrom headwater streams to oceans dissolved PyC increases in radiocarbon age, implying environmental persistenceEnvironmental controls, including climate, topography, biota, parent material, and time, impact the pool size and flux of dissolved PyC [ABSTRACT FROM AUTHOR]

The Amazon River Basin's extraordinary social-ecological system is sustained by various water phases, fluxes, and stores that are interconnected across the tropical Andes mountains, Amazon lowlands, and Atlantic Ocean. This "Andes-Amazon-Atlantic" (AAA) pathway is a complex hydroclimatic system linked by the regional water cycle through atmospheric circulation and continental hydrology. Here, we aim to articulate the AAA hydroclimate pathway as a foundational system for research, management, conservation, and governance of aquatic systems of the Amazon Basin. We identify and describe the AAA pathway as an interdependent, multidirectional, and multiscale hydroclimate system. We then present an assessment of recent (1981 to 2020) changes in the AAA pathway, primarily reflecting an acceleration in the rates of hydrologic fluxes (i.e., water cycle intensification). We discuss how the changing AAA pathway orchestrates and impacts social-ecological systems. We conclude with four recommendations for the sustainability of the AAA pathway in ongoing research, management, conservation, and governance. [ABSTRACT FROM AUTHOR]

In the present work, graphitic carbon nitride/GO/V2O5 nanocomposite was synthesized via a single stage and utilized this photocatalyst for the degradation of the pesticide Chlorpyrifos. The nanocomposite was prepared using the hydrothermal method. The crystal structure was determined using powder X-ray diffraction of ternary nanocomposite material crystallite size, phase, and defects. Scanning electron microscopy (SEM) and FT-IR evaluated surface morphologies and functional groups. FTIR heterocycle C–N and C=N stretching modes due to bands of 1200–1650 cm−1 During the course of the experiment, the impacts of the experimental parameters (such as pH, time, H2O2 concentration, and Catalyst Dose) on the degradation of Chlorpyrifos were investigated. The photocatalytic studies indicated that the graphitic carbon nitride/GO/V2O5 composites significantly outperformed the pure versions of g-C3N4 in photocatalytic degradation of Chlorpyrifos. The excellent photocatalytic removal efficiency of more than 88% in 120 min obtained using a graphitic carbon nitride/GO/V2O5 catalyst pointed toward a great alternative catalyst for the treatment of Chlorpyrifos and other hazardous pesticides from wastewater. By using 0.1% H2O2, the photocatalytic elimination of Chlorpyrifos was further increased from 88 to 90.5%. The g-C3N4/GO/V2O5 catalyst has outstanding recycling performance and a high level of stability. [ABSTRACT FROM AUTHOR]

The fully aquatic Japanese giant salamander (Andrias japonicus) is a member of the Cryptobranchidae, and is currently distributed in western Japan, with other members of this group restricted to China and North America. Their feeding behaviour is characterized by a form of suction feeding that includes asymmetric movements of the jaw and hyobranchial apparatus. Previous studies on the North American species, Cryptobranchus alleganiensis, have suggested that this specialized jaw movement is produced by a flexible quadrate‐articular joint combined with a loosely connected lower jaw symphysis including two small fibrocartilaginous pads. However, little is known about this feeding behaviour in the Asian species, nor have the three‐dimensional asymmetric jaw movements been fully investigated in any member of Cryptobranchidae. In this study, we explore the asymmetric jaw movements in A. japonicus using three methods: (1) dissection of musculoskeletal structures; (2) filming of feeding behaviour to understand in which situations asymmetric feeding is used; (3) analysis of 3D movement of jaws and skull. In the third component, fresh (from frozen) specimens of A. japonicus were manipulated to replicate asymmetric and symmetric jaw movements, with the specimens CT scanned after each step to obtain the 3D morphology of the jaws at different positions. These positions were combined and their Euler angles from resting (closed) jaw position were calculated for asymmetric or symmetric jaw positions. Our filming revealed that asymmetric jaw movements are linked to the position of the prey in relation to the snout, with the jaw closest to the prey opening asymmetrically. Moreover, this action allows the salamander to simultaneously grasp prey in one side of the mouth while ejecting water on the other side, if the first suction attempt fails. The asymmetric jaw movements are performed mainly by rotation of the mandible about its long axis, with very limited lateral jaw movements. During asymmetric and symmetric jaw movements, the posterior ends of the maxilla and quadrate move slightly. The asymmetric jaw movements are permitted by a mobile quadrate‐articular joint formed by wide, round cartilages, and by two small fibrocartilage pads within the jaw symphysis that act as cushions during jaw rotation. Some of these soft tissue structures leave traces on the jaws and skull, allowing feeding mode to be reconstructed in fossil taxa. Understanding cryptobranchid asymmetric jaw movement thus requires a comprehensive assessment of not only the symphysial morphology but also that of other cranial and hyobranchial elements. [ABSTRACT FROM AUTHOR]

Antimicrobial resistance (AMR) in pathogens important to aquatic animal health is of increasing concern but vastly understudied. Antimicrobial therapy is used to both treat and prevent bacterial disease in fish and is critical for a viable aquaculture industry and for maintenance of wild fish populations. Unfortunately, phenotypic antimicrobial susceptibility testing is technically difficult for bacteria recovered from aquatic animal hosts resulting in challenges in resistance monitoring using traditional methods. Whole-genome sequencing provides an appealing methodology for investigation of putative resistance. As part of the ongoing efforts of the FDA CVM Vet-LIRN to monitor AMR, source laboratories cultured and preliminarily identified pathogenic bacteria isolated from various fish species collected in 2019 from across the United States. Sixty-one bacterial isolates were evaluated using whole-genome sequencing. We present here the assembled draft genomes, AMR genes, predicted resistance phenotypes, and virulence factors of the 61 isolates and discuss concurrence of the identifications made by source laboratories using matrix-assisted laser desorption/time-of-flight mass spectrometry. [ABSTRACT FROM AUTHOR]

One-Health is an umbrella term that integrates the health of the environment, humans and non-human animals. This approach is applied here to elucidate the impact of non-native invasive species on aquaculture and food security. Despite inherent biases against these species, a better understanding of their characteristics allows for the identification of those of greatest concern, minimizing the risk of food shortages and infectious diseases. This review summarises the positive and negative impacts of non-native species, delineating the specific areas they may impact. Additionally, this review gives an insight to the expertise and stakeholders that would need to be included if a "One-Health" approach were to be implemented by policymakers to better control non-native species. Detailed examples illustrate the consequences of non-native species on trophic dynamics, ecosystem health, water chemistry, and human health, emphasizing the importance of managing them within a multidimensional framework. The "One-Health" approach is explained, and suggestions are made on how certain non-native species could be used to contribute to food security in low- and middle-income countries. Furthermore, recommendations are made to promote a more inclusive management strategy. [ABSTRACT FROM AUTHOR]

Freshwater ecosystems are responsible for a large proportion of global methane emissions to the atmosphere. The radiocarbon (14C) content of this aquatic methane is useful for determining the age and source of this important greenhouse gas. Several methods already exist for the collection of aquatic methane for radiocarbon analysis, but they tend to only sample over short periods of time, which can make them unsuitable for characterizing aquatic methane over longer timespans, and vulnerable to missing short-term events. Here, we describe a new time-integrated method for the collection of aquatic methane that provides samples suitable for radiocarbon analysis, that are representative for periods of up to at least 16 days. We report the results of a suite of tests undertaken to verify the reliability of the method, and the 14C age of aquatic methane from field trials undertaken at sites within Scotland, UK. We believe that this new method provides researchers with a simple approach that is easily deployable and can be used to collect representative time-integrated samples of methane for radiocarbon analysis from a wide range of aquatic environments. [ABSTRACT FROM AUTHOR]

In this study, response surface methodology (RSM) was used to optimize in vitro regeneration of the Brazilian micro sword (Lilaeopsis brasiliensis) aquatic plant, followed by data prediction and validation using machine learning algorithms. The basal salt, sucrose and Benzyaminopurine (BAP) concentrations were derived from Box-Behnken design of RSM. The response surface regression analysis revealed that 1.0 g/L MS + 0.1 mg/L BAP + 25 g/L sucrose was optimized for maximum regeneration (100%), shoot counts (63.2), and fresh weight (1.382 g). The RSM-based predicted scores were fairly similar to the actual scores, which were 100% regeneration, 63.39 shoot counts, and 1.44 g fresh weight. Pareto charts analysis illustrated the significance of MS for regeneration and fresh weight but remained insignificant. Conversely, MS × BAP was found to be the most crucial factor for the shoot counts, with MS coming in second and having a major influence. The analysis of the normal plot ascertained the negative impact of elevated MS concentration on shoot counts and enhanced shoot counts from the combination of MS × BAP. Results were further optimized by constructing contour and surface plots. The response optimizer tool demonstrated that maximum shoot counts of 63.26 and 1.454 g fresh weight can be taken from the combination of 1.0 g/L MS + 0.114 mg/L BAP + 23.94 g/L. Using three distinct performance criterias, the results of machine learning models showed that the multilayer perceptron (MLP) model performed better than the random forest (RF) model. Our findings suggest that the results may be utilized to optimize various input variables using RSM and verified via ML models. Key message: Optimization of in vitro whole plant regeneration of Brazilian sword wood using response surface methodology Data analysis through ANOVA, response surface regression anlaysis and machine learning Graphical presentation of data via Pareto charts, normal plots, contour plots and surface plots for optimization Better performance of ANN-based MLP model compared to decision tree based RF model [ABSTRACT FROM AUTHOR]

This paper sheds light on the alarming issue of antibiotic resistance (ABR) in aquatic environments, exploring its detrimental effects on ecosystems and public health. It examines the multifaceted role of antibiotic use in aquaculture, agricultural runoff, and industrial waste in fostering the development and dissemination of resistant bacteria. The intricate interplay between various environmental factors, horizontal gene transfer, and bacterial extracellular vesicles (BEVs) in accelerating the spread of ABR is comprehensively discussed. Various BEVs carrying resistance genes like blaCTX-M, tetA, floR, and sul/I, as well as their contribution to the dominance of multidrug-resistant bacteria, are highlighted. The potential of BEVs as both a threat and a tool in combating ABR is explored, with promising strategies like targeted antimicrobial delivery systems and probiotic-derived EVs holding significant promise. This paper underscores the urgency of understanding the intricate interplay between BEVs and ABR in aquatic environments. By unraveling these unseen weapons, we pave the way for developing effective strategies to mitigate the spread of ABR, advocating for a multidisciplinary approach that includes stringent regulations, enhanced wastewater treatment, and the adoption of sustainable practices in aquaculture. [ABSTRACT FROM AUTHOR]

During the present study, the evolutionary relationship within a clade of mountain clade of freshwater crabs (Potamonautes) was examined using mtDNA sequence data for species from the Cape Fold Mountain (CFM) and Great Escarpment (Drakensberg Mountain range). We undertook phylogenetic analyses, divergence time estimation, and an ancestral area reconstruction to explore the period of cladogenesis and understand the biogeographic history in this high‐altitude clade. Furthermore, we applied four species delimitation methods using ASAP, bPTP, bGMYC, and STACEY on the latter clade. Bayesian phylogenetic analyses retrieved a monophyletic freshwater crab clade comprised of two major sister clades, one comprised of the Cape Fold (clade A) and two comprised of Drakensberg Mountains (clade B) species. Divergence time estimation indicated that the two clades underwent Mio/Pliocene cladogenesis. Within the CFM clade (A), P. amathole (Amathola Mountains) was sister to P. parvispina (Cederberg and Kouebokkeveld Mountains) and the latter species were sister to P. parvicorpus (Cape Peninsula, Jonkershoek, and Helderberg Mountains) sister to P. tuerkayi (Overberg Mountains) and P. brincki (Hottentots Holland Mountains). Within the Drakensberg Mountain clade (B), we observed in situ diversification. Specimens from the southcentral Drakensberg Mountains (Dargle Forest, Injasuti, Karkloof, and Impendle) represent a new undescribed lineage Potamonautes sp. nov. 1. The second clade from the northern Drakensberg, representing P. clarus, was sister to a central Drakensberg Mountain clade that comprised P. depressus that was in turn sister to P. baziya from the Eastern Cape Province. The application of species delimitation methods generally overestimated the number of species. The biogeographic analyses indicated that the Eastern Cape Province is the most likely ancestral range area. Ecological niche modelling of representative species in clades A (Cape Fold Mountains) and B (Drakensberg Mountains) demonstrated that temperature and rainfall were the major abiotic drivers that differentiated the two clades. Our data favours the mountain gradient speciation hypothesis. [ABSTRACT FROM AUTHOR]