Journal of fish biology最新文献

{"title":"New insights into the putative XX/XY sex chromosomal system in blue-eyed red-fin pleco Hypostomus soniae (Siluriformes, Loricariidae).","authors":"Luan Aércio Melo Maciel, Renata Coelho Rodrigues Noronha, Bruno Rafael Ribeiro de Almeida, Manoella Gemaque Cavalcante, Cleusa Yoshiko Nagamachi, Julio Cesar Pieczarka, Luís Reginaldo R Rodrigues","doi":"10.1111/jfb.70226","DOIUrl":"https://doi.org/10.1111/jfb.70226","url":null,"abstract":"<p><p>Blue-eyed red-fin pleco Hypostomus soniae (family Loricariidae) presented a putative sex system XX/XY in early stage. Aiming to explore the inter-populational karyotypic variation and proposed emergence of the XX/XY system, we studied 13 H. soniae individuals (6 males, 7 females) from the Tapajós River. Mitotic karyotypes and meiotic cells were analysed using C-banding, site verification Ag-NOR (nucleolar organizing region), chromomycin A₃ (CMA3) and fluorescent in situ hybridization with repetitive DNA probes (DNAr 18s, 5S, histone H1, H3, telomere). The synaptonemal complex on meiocytes was studied using immunodetection with anti-structural maintenance of chromosomes protein 3, anti-γH2AX and anti-H3K9ac. The karyotype presented was 2n = 64, with clear size heteromorphism varying between male and female. The species presented multiple NORs colocalized with 18S and CMA3-positive marks in two pairs of acrocentric chromosomes. The centromeric region of pairs 25 and 26 carries the repeats of histones H1 and H3. All the bivalents at pachytene exhibited tip-to-tip pairing, revealing the absence of an XY pair with partial synapsis. The synaptic behaviour of the putative sexual pair failed to corroborate the XX/XY system hypothesis in H. soniae. Further cytogenetic and molecular investigations are necessary to determine the proposed emergence of an XX/XY sexual system in H. soniae and the regulatory mechanisms underlying its atypical meiotic behaviour.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145053721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The role of angiotensin II to support arterial blood pressure following serial haemorrhage in the freshwater channel catfish (Ictalurus punctatus).","authors":"K Austin Davis, Max G Sanderford","doi":"10.1111/jfb.70229","DOIUrl":"https://doi.org/10.1111/jfb.70229","url":null,"abstract":"<p><p>Reductions in blood volume and changes to environmental salinity are known regulators of the renin-angiotensin system (RAS) in marine and euryhaline species of fish. However, the mechanisms activating the RAS in freshwater stenohaline species remain poorly understood. The purpose of this study was to determine if reduction in blood volume stimulates the activation of the RAS in channel catfish (Ictalurus punctatus). To achieve this goal, this study sought to determine if angiotensin II (ANG II) functions to support arterial blood pressure following a moderate haemorrhage. Channel catfish (n = 12) were implanted with a dorsal aortic catheter to measure dorsal aortic pressure (P_DA), infuse drugs and sequentially withdraw four volumes of blood to produce an estimated 20% reduction in blood volume in a group of randomly sampled fish (n = 6), whereas the remaining fish (n = 6) were not haemorrhaged. Stepwise haemorrhage marginally reduced P_DA while significantly increasing heart rate. After haemorrhage or time control, infusion of the angiotensin-converting enzyme inhibitor captopril significantly reduced P_DA to a greater degree in haemorrhaged fish than non-haemorrhaged fish. Additionally, captopril reduced heart rate in haemorrhaged fish compared to non-haemorrhage fish. These results suggest that reduction in blood volume activates the RAS in the freshwater channel catfish. Also, these data suggest that the RAS of channel catfish may play a role in central neural mechanisms regulating heart rate.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145040337","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Genomic structure and diversity of European polyploid spined loaches (Cypriniformes, Cobitidae) in a situation of genetic instability.","authors":"Sergiy V Mezhzherin, Anton O Tsyba","doi":"10.1111/jfb.70215","DOIUrl":"https://doi.org/10.1111/jfb.70215","url":null,"abstract":"<p><p>The European di-, tri- and tetraploid complex of spined loaches of the genus Cobitis is formed by hybridization of C. elongatoides and three vicarious species, С. taenia, C. tanaitica and C. pontica. It is represented in the form of populations in which parental or related species сoexist with polyploids that reproduce gynogenetically. Insufficient geographic coverage and the unclear genomic composition of certain polyploids and their genetic instability limit the understanding of the diversity and origin of polyploids. This study used allozyme markers, cytometry and karyotyping of spined loaches from six main Ukrainian river systems to reveal a zone of gene introgressions between vicarious species and the presence of di-, tri- and tetraploid hybrids that resulted from the hybridization of C. elongatoides with С. taenia, C. tanaitica and C. pontica vicarious species group representatives. In total, 11 allopolyploid biotypes were identified. Autochthonous biotypes coexist with parental species and partly arise de novo. Allochthonous biotypes form mixed populations with non-parental species and reproduce by cloning. Relict allochthons originated in the past from species whose areas are now separated. At the same time, they are the most abundant in the aquatic systems of Ukraine, except for the Danube basin. Besides the initial subbiotypes, which have allozyme sets corresponding to the gene pools of the parental species, there are also altered ones with derivative allozyme spectra and gene dosage effect anomalies. They result from genetic instability and appear sporadically or massively when their frequency among polyploids in certain populations reaches 97%. In the latter case, their occurrence should be attributed to the pollution of water systems. In addition, there are biotypes with the ambiguous genomic structure and consequently they are of unclear origin.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145040386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distribution modelling for Neotropical freshwater stingrays Potamotrygon brachyura and Potamotrygon motoro (Myliobatiformes, Potamotrygonidae) in the Uruguay River basin.","authors":"Danilo Araujo Soares Pereira, Roberto E Reis, Nelson F Fontoura","doi":"10.1111/jfb.70219","DOIUrl":"https://doi.org/10.1111/jfb.70219","url":null,"abstract":"<p><p>This study aimed to identify geographical distribution patterns of the giant short-tailed river stingray Potamotrygon brachyura and the motoro stingray Potamotrygon motoro in the Uruguay River basin. Data on presence/absence of stingrays were based on fishers' knowledge accessed by interviews through expeditions in Brazil, Argentina and Uruguay. The significance in independent variables (environmental descriptors) of elevation (p = 0.00 for both species), upstream distance (p = 0.02 for P. brachyura and 0.03 for P. motoro) and downstream distance (p = 0.00 for both species) explained the presence of stingrays in the main water bodies of lower Uruguay and their absence throughout upper Uruguay more than the biogeographical barrier of the Salto de Yucumã (p = 0.99 for both species) and basin area (p = 0.42 for P. brachyura and p = 0.43 for P. motoro) in the last steps. The construction of logistic models also provided high sensitivity (96.3%-97.5% for P. brachyura and 62.3%-71.7% for P. motoro) and specificity (86.8% for P. brachyura and 85.4%-86.5% for P. motoro) results between observed and presumed distribution for both species, with values of false positive and false negative varying between 1.3%-14.1% and 6.4%-9.2%, respectively. Further studies are still necessary not only in the Uruguay River basin or the La Plata basin complex, but for all South America, considering potential changes in the state of knowledge of freshwater biodiversity and its geographical distribution, including the possibility of undescribed species.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145040384","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the population structure of Plagioscion squamosissimus (Teleostei, Perciformes, Sciaenidae) from the São Francisco River, Bahia, Brazil, using body morphology and otolith shape signatures.","authors":"F L Freitas, N S Pereira, P B Pinheiro, R Schroeder, A T Correia","doi":"10.1111/jfb.70221","DOIUrl":"https://doi.org/10.1111/jfb.70221","url":null,"abstract":"<p><p>The south American silver croaker, Plagioscion squamosissimus, holds significant importance for the artisanal fisheries in the sub-middle and lower courses of the São Francisco River, located in northeastern Brazil. To investigate the population structure of this species along its longitudinal profile, a total of 150 individuals (50 fish per site), measuring between 35 and 45 cm in standard length, were collected from three fishers' associations (Olhos D'água do Casado, Petrolândia and Rodelas) using gill nets from September 2023 to March 2024. Morphometry analyses of body shape were conducted using two landmark-based geometric morphometrics: Procrustes coordinates (PCs) and truss networking (TD). Additionally, otolith shape was examined through two otolith contour analyses: wavelet transform coefficients (WTCs) and elliptic Fourier descriptors (EFDs). Both univariate and multivariate statistical approaches were employed to assess the data. The findings revealed a significant secondary sexual dimorphism in otolith shape that was not observed in body shape. This dimorphism may be linked to sex-specific hearing adaptations associated with ecological or reproductive behavioural strategies, although further research is required to test this hypothesis. Despite this sexual dimorphism, the overall reclassification success rate of individuals to their original sites was notably high, ranging from 91% to 94% using body morphometry (TD and PCs, respectively), and reaching 100% accuracy with otolith shape analysis (EFDs and WTCs). The phenotypic differences observed among local populations likely resulted from distinct environmental conditions between sites, probably caused by the construction of two hydroelectric plants that disrupted fish connectivity along the São Francisco River. The results suggest that P. squamosissimus populations captured in the sub-middle and lower courses of the river constitute distinct population-units. This distinction has critical implications for the species' management and conservation strategies.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145040390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative insights into the spatio-temporal variation of Atlantic salmon (Salmo salar) biomass in a river catchment using eDNA metabarcoding.","authors":"William Bernard Perry, Nigel Milner, Ifan Bryn Jâms, Mark de Bruyn, Steve J Ormerod, Kristy Deiner, Holly M Bik, Gary Carvalho, John Colbourne, Bernard Jack Cosby, Isabelle Durance, Simon Creer","doi":"10.1111/jfb.70172","DOIUrl":"https://doi.org/10.1111/jfb.70172","url":null,"abstract":"<p><p>Effective species conservation and management requires comprehensive biomonitoring, enhanced by combining traditional and newer methodologies, such as environmental DNA (eDNA) analyses. A seasonal pulse of spawning adult Atlantic salmon (Salmo salar) was detected by normalised eDNA 12S reads from metabarcoding, which facilitated estimation of spatial patterns in salmon biomass. A strong relationship was found between normalised reads in the lower section of the River Conwy (Wales, UK) and whole-river adult biomass (estimated from rod catch data and a fish counter), explaining 61% of the variation in a linear regression. Moreover, the positive linear relationship between adult biomass and partial effect on normalised reads occurred after the biomass estimate exceeded 1500 kg, indicating a threshold where normalised reads become representative of biomass. The relationship observed between normalised reads and biomass, as well as the unique profiles of normalised reads at each of the sites, supports the hypothesis of limited eDNA transport among sampling sites that were 2-4 km apart. River pH showed a significant non-linear relationship with normalised reads, with a peak in partial effect on normalised reads at pH 6.5. Partial effect on normalised reads also showed a positive linear relationship with flow (discharge), while also peaking at the highest average monthly air temperatures (14°C). These trends are contrary to what would be expected from eDNA decay, dilution or transport, demonstrating that metabarcoding is robust to such influences, reinforcing the interpretation of trends driven by Atlantic salmon ecology and physiology. For example, pH effects reflect beneficial conditions for eggs and perhaps habitat preference for spawners, flow effects reflect the annual return of salmon during higher flows which aid upstream migration, tributary entry and spawning, and, finally, temperature effects reflect higher metabolic rates and greater shedding of eDNA.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145040341","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fish eye growth rate and vertical habitat: A maximum for eye growth rate investment in the mesopelagic zone.","authors":"Jérôme Pinti, Alexia Elizardo, Samuel Hankinson, Madelynne Reifsteck, Renea Briner, Mia Carulli, Trinity Clifford, Jonathan H Cohen, Aaron B Carlisle","doi":"10.1111/jfb.70201","DOIUrl":"https://doi.org/10.1111/jfb.70201","url":null,"abstract":"<p><p>Vision is one of the most important means by which animals perceive their environment. In the pelagic ocean, there is an enormous gradient of available light from the well-lit surface to the deep bathypelagic zone. Fish inhabiting different depths of the pelagic ocean must adapt to these conditions. One of the ways to optimize sensitivity (i.e., the ability to detect light) in dim environments is to increase eye size, increasing the probability of a photon hitting the retina. Here, we investigate how fish eye investment (i.e., the relative eye vs. body growth rate) varies based on the maximum residence depth of fishes. We measured eye diameter, eye area and lengths from 5639 unique individuals, belonging to 551 species and 37 orders, and extracted ecological traits for these species. We found that there was a wide variety of fish eye investment strategies across depths. These strategies, however, were bounded by a depth-dependent maximum eye investment that peaked at around ~500 m before decreasing as fish resided in deeper depths. These results suggest that, although a multitude of strategies are viable at each depth, there is a depth-dependent limit to how advantageous eye investment is. The depth at which a high eye investment is the most beneficial is located in the middle of the mesopelagic zone in very dim conditions - but where sunlight still penetrates and where bioluminescence occurs. All individual fish measurements and all species traits are available as supplementary material, representing a valuable resource for future pelagic fish trait-based studies.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145033418","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Life cycle, natural mortality and exploitation rate of Totoaba macdonaldi.","authors":"Miguel Á Cisneros-Mata, Marcelo V Curiel-Bernal","doi":"10.1111/jfb.70159","DOIUrl":"https://doi.org/10.1111/jfb.70159","url":null,"abstract":"<p><p>Natural mortality rate (M) is a crucial parameter for fish and other species. In fisheries management it is common practice to obtain estimates of M using one of several empirical formulas available in the literature. However, when using these formulas, an important question arises: for which life stage or age does the estimated rate pertain to? In the present work, gnomonic stage-specific mortality rates are estimated for Totoaba macdonaldi, a vulnerable fish species of the gulf of California. The gnomonic method is based on knowledge of the species life cycle; it tracks numbers surviving during exponential decay of a cohort under specific restrictions. An average weighted mortality rate of 0.108/year is then computed for adults and senescent fish subjected to poaching. This allowed us to ascertain status of the population calculating exploitation rate (80%). It is concluded that the totoaba population is under heavy overexploitation.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145033372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Trophic guilds of cichlid species in a floodplain river.","authors":"Honor T Ifon, Philomena E Asuquo, George E Eni, Gabriel U Ikpi","doi":"10.1111/jfb.70223","DOIUrl":"https://doi.org/10.1111/jfb.70223","url":null,"abstract":"<p><p>Floodplains support a diverse cichlid community, yet the trophic ecology of these species is not well understood. This study investigated the dietary niches and trophic guilds of cichlid species in the Cross River floodplain. A total of 480 fish samples from eight cichlid species were collected from three locations (Itu, Obubra, Ikom) over 6 months (October 2019-March 2020). Dietary analysis revealed notable variations in food preferences among species, with algae being the dominant food for Tropheus sudanensis (63.8%) and Streptocara melanotheron (28.8%). Molluscs and crustaceans were primary foods for Oreochromis placidus (25% molluscs and 46.8% crustaceans), indicating a carnivorous feeding strategy. Oreochromis niloticus (57.3%) and Coptodon mariae (63.2%) showed a preference for plant parts, whereas Coptodon guntheri (89.5%) predominantly consumed insects. Correspondence analysis revealed that C. mariae and O. niloticus were strongly associated with plant parts, whereas Coptodon guineensis preferred crustaceans. Canonical correspondence analysis (CCA) identified four trophic guilds: insectivores, benthivores, herbivores and algivores, with two sub-guilds within the benthivores - crustacivores and molluscivores. The first CCA dimension explained 76% of the variance (inertia = 1.492), which was statistically significant (p < 0.01), confirming the distinct feeding strategies of the cichlids. These findings underscore the specialization within cichlid diets and the presence of specialized sub-guilds within the benthivores. It is recommended that future studies investigate the ecological roles of these trophic guilds in floodplain biodiversity conservation and ecosystem management.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145029982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Drone observations reveal white shark (Carcharodon carcharias) dorsal fins are highly flexible and possible investigatory structures.","authors":"Carlos Gauna, Phillip C Sternes","doi":"10.1111/jfb.70210","DOIUrl":"https://doi.org/10.1111/jfb.70210","url":null,"abstract":"<p><p>Drones are becoming increasingly useful in their ability to observe wildlife. They have been especially useful in documenting marine animals such as sharks. Here we present novel aerial drone observations of a previously unknown dorsal-fin behaviour in white sharks (Carcharodon carcharias). We found that white sharks might investigate surface objects by rotating their first dorsal fin on its axis towards the object. Our videos suggest that the dorsal fin in white sharks may have additional capabilities beyond being a stabilizing appendage.</p>","PeriodicalId":15794,"journal":{"name":"Journal of fish biology","volume":" ","pages":""},"PeriodicalIF":2.0,"publicationDate":"2025-09-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145029952","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}