Zoological Studies最新文献

{"title":"The Sea Spider Genus <i>Hannonia</i> Hoek, 1881 (Pycnogonida): A Review and Two New Species.","authors":"Romain Sabroux","doi":"10.6620/ZS.2026.65-31","DOIUrl":"https://doi.org/10.6620/ZS.2026.65-31","url":null,"abstract":"<p><p><i>Hannonia</i> is a particularly rare and poorly studied genus, which includes four species distributed along the shores of Africa and Europe. Here, two new species are described from the southern shores of Madagascar, <i>Hannonia arnaudae</i> sp. nov. and <i>Hannonia laurae</i> sp. nov. sampled during the ATIMO VATAE expedition (<i>Muséum national d'Histoire Naturelle</i> survey, 2010). DNA barcoding data were successfully obtained for the holotype of <i>H. arnaudae</i> sp. nov. Besides, additional material sampled by Bernard Thomassin at Nosy-Vé and Tuléar in July 1972 are reported: these specimens present strong affinities to the newly described <i>H. arnaudae</i> sp. nov., but consistently exhibit slight morphological deviations from the holotype description. In absence of DNA barcoding data for this material, it was not possible to estimate whether these variations were significant, preventing their formal identification to the species level. A checklist and a new identification key for the genus are also provided, together with additional morphological information for <i>Hannonia stocki</i> Munilla, 1993.All <i>Hannonia</i> species except <i>Hannonia typica</i> Hoek, 1881 were sampled in only one locality, making their geographic and bathymetric distribution range unpredictable. The genus is potentially present on the western shores of the African continent, highlighting the need for further investigation in these regions where sea spiders are rarely surveyed. The affinities of <i>Hannonia</i> with the 11 currently accepted pycnogonid families need to be investigated through phylogenetic studies to be properly understood. Morphological comparisons suggest possible affinities between this genus and two other Southern Africa pycnogonid genera of uncertain taxonomic placement, <i>Boehmia</i>, and <i>Queubus</i>, highlighting further the importance of integrating African pycnogonids to future research on sea spider diversity and evolution.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"65 ","pages":"e31"},"PeriodicalIF":1.4,"publicationDate":"2026-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13579321/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148992224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cytogenetics of Four Turtle Ants from the Amazon: First Steps Towards Understanding Karyotype Evolution in <i>Cephalotes</i>.","authors":"Paulo C Ferreira, Luísa A C Barros, Linda I Silveira, Maria L L Teixeira, Gisele A Teixeira, Hilton J A C de Aguiar","doi":"10.6620/ZS.2026.65-32","DOIUrl":"https://doi.org/10.6620/ZS.2026.65-32","url":null,"abstract":"<p><p>Ants of the genus <i>Cephalotes</i> have unique morphological traits, with morphotypes specifically adapted to arboreal habitats, earning them the common name \"turtle ants\". In the Americas, 118 <i>Cephalotes</i> spp. have been identified, 64 in Brazil. Phylogenetic studies suggest 15 distinct groups of <i>Cephalotes</i> spp. In this context, cytogenetics emerges as a valuable tool for comprehending the diversification of these clades. This study used cytogenetics to characterize four <i>Cephalotes</i> spp. from the northernmost Brazilian state of Amapá. The number, morphology, and locations of specific DNA sequences varied. Most chromosomes were metacentric; <i>C. atratus</i> had a low chromosome number (2n = 22), compared to <i>C. minutus</i>, <i>C. pavonii</i>, and <i>C. simillimus</i> (2n = 44, 2n = 42, and <i>n</i> = 22, respectively). Ribosomal genes were restricted to a single chromosome pair which were present within pericentromeric regions in <i>C. atratus</i> and <i>C. simillimus</i>, interstitial region in <i>C. pavonii</i> and terminal region in <i>C. minutus</i>. The microsatellite (GA)_n was clustered only in <i>C. atratus</i>; whereas in species with high chromosome numbers, this microsatellite was absent on one arm of several chromosome pairs. The telomeric (TTAGG)n motif was restricted to the chromosome ends in <i>C. atratus</i> as expected. Our findings suggest that centric fission, along with occasional chromosomal inversion events are principal mechanisms driving karyotype evolution in <i>Cephalotes</i> spp. Combining the cytogenetic data on <i>Procryptocerus</i> spp., we suggest that the putative ancestral karyotype of <i>Cephalotes</i> has 2n = 22 chromosomes. Cytogenetic analyses of a broader diversity of <i>Cephalotes</i> spp. are essential to elucidate whether fission events represent lineage-specific innovations or shared ancestral processes. They may provide deeper insights into the evolutionary dynamics underlying chromosomal architecture and its role in the diversification of these ecologically specialized turtle ants.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"65 ","pages":"e32"},"PeriodicalIF":1.4,"publicationDate":"2026-07-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13579319/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148992242","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Proximity to Humans Reduces Distance to Foraging Sites by Aardvarks.","authors":"Nolutho Makwati, Zivanai Tsvuura, Manqhai Kraai","doi":"10.6620/ZS.2026.65-33","DOIUrl":"https://doi.org/10.6620/ZS.2026.65-33","url":null,"abstract":"<p><p>Aardvarks change the ecosystem through digging for food and shelter thus providing habitats for various animals in sub-Saharan Africa. We determined use of the landscape and foraging behaviour of aardvarks in a communal area. We aged and quantified aardvark foraging burrows and dens in the dry, wet and early dry seasons of 2020 and 2021 in Ncunjane village of KwaZulu-Natal Province, South Africa. We used 50 m × 10 m belt transects to quantify aardvark foraging burrows in each site of aardvark activity. For each aardvark foraging burrow, we determined age and measured the maximum depth and two perpendicular lengths on the ground surface. We recorded numbers of active dens, active and inactive entrances for each den, distances between active entrances of a den and size of the den. We recorded any animal activity or trace (<i>e.g.</i>, animal faeces and spider webs) on the den entrances. Aardvarks dug shallow and deep foraging burrows in the wet and dry seasons, respectively. All seasons comprised a greater number (> 51%) of old than new and very old foraging burrows. Aardvarks showed human avoidance by restricting their foraging activities to the rangeland rather than within the village. Dens were constructed close (within 50 m) to feeding areas, which may be necessary in a human-dominated environment. Villagers closed den entrances closer to homes with rocks to prevent snake habitation and used the den entrances as dumping sites for rubbish and disposable nappies. Ultimately, aardvarks appeared to regulate their behaviour by keeping their activities in the outskirts of the village, feeding closer to dens, creating many entrances for escape and thus limited space utilised compared to their counterparts in protected areas. Human activities will likely drive aardvarks away or facilitate local extinction. The study encourages active conservation efforts in marginalised communal areas.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"65 ","pages":"e33"},"PeriodicalIF":1.4,"publicationDate":"2026-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13579320/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148992174","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sunlight Sonata: Contrasting the Roles of Solar Ultraviolet Radiation and Temperature on the Calling Behavior of a Diurnal Forest-specialist Frog.","authors":"Álvaro A Mainardi, Vinícius M Caldart, Mauricio Beux Dos Santos, Nelson J Schuch, André P Schuch","doi":"10.6620/ZS.2026.65-22","DOIUrl":"10.6620/ZS.2026.65-22","url":null,"abstract":"<p><p>Diurnal animals are frequently exposed to solar ultraviolet radiation (UV) during their daily activities, which can lead to DNA damage and other physiological challenges. To counteract these effects, they have evolved complex DNA repair mechanisms. The high energetic cost of DNA repair creates a trade-off with behavior, potentially constraining energetically demanding activities like anuran calling under harmful UV exposure. We tested hypotheses on how natural heterogeneity in the abiotic environment - particularly in the UV radiation - influences the calling behavior of <i>Crossodactylus schmidti</i>, a diurnal forest-specialist frog found in preserved neotropical streams. To gather data on male calling behavior, we used passive acoustic monitoring of a well-studied population, using a set of recorders and data loggers that measured short- and long-term cumulative doses of UVA and UVB, air temperature, light intensity and cloud cover during the austral summer. To investigate associations between the abiotic variables and proxies of calling behavior (occurrence, number, and duration of calls), we used a model selection approach based on generalized linear mixed models followed by model averaging of the best-supported models. We found that: 1) the probability of recording males in calling behavior decreased with increasing mean air temperature and cumulative UVB dose but increased with short-term (15-minute) UVB exposure; 2) the number of calls emitted by males decreased with increasing mean air temperature but increased with cumulative UVB dose; and 3) call duration decreased with increasing mean air temperature but increased with cumulative UVB dose at calling sites. Short- and long-term doses of UVA, on the other hand, did not influence any proxy of calling behavior. Our findings show that higher temperatures in months of peak calling activity consistently reduce calling behavior, while UVB exposure has more complex effects. Together, these results underscore the need to consider both thermal and ultraviolet components of sunlight when assessing how anurans respond behaviorally to abiotic heterogeneity under ongoing environmental and climatic changes.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"65 ","pages":"e22"},"PeriodicalIF":1.4,"publicationDate":"2026-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13463198/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148726886","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A New Species of <i>Thrissina</i> from Philippines (Teleostei: Clupeiformes: Engraulidae) with Comments on the Biogeography and Speciation of this Genus in Southeast Asia.","authors":"Harutaka Hata, Sébastien Lavoué, Mudjekeewis D Santos, Lauren Sallan","doi":"10.6620/ZS.2026.65-30","DOIUrl":"10.6620/ZS.2026.65-30","url":null,"abstract":"<p><p><i>Thrissina invicta</i> sp. nov. is described based on 46 specimens collected from Philippine Islands. The new species is morphologically most similar to <i>Thrissina katana</i> Hata, Lavoué and Motomura 2022, <i>Thrissina malabarica</i> (Bloch 1795), and <i>Thrissina mystica</i> Hata, Lavoué and Motomura 2025, three species previously included in \"<i>Thryssa hamiltonii</i>.\" However, <i>Thrissina invicta</i> sp. nov. differs from these species by several morphological metrics including higher counts of gill rakers and lower counts of vertebrae, as well as both a longer head and a deeper body. The new species is most likely to be the sister taxon to <i>T. katana</i> due to their close morphological similarity based on preserved specimens in museums, but this is yet to be confirmed by genetic analysis. If they are sister taxa, their divergence may have resulted from allopatric speciation during the long isolation of shelf areas around the Philippine Islands from those around Sundaland (now the islands of Southeast Asia, Indonesia, Brunei and Malaysia) during Pleistocene era intervals of low sea levels associated with glacial maxima. The current overlapping distribution of <i>Thrissina invicta</i> sp. nov. and <i>T. katana</i> off Palawan Island is interpreted as a secondary contact zone, highlighting the influence of both Philippine Islands and Sundaland in the assembling of the marine ichthyofauna of this island.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"65 ","pages":"e30"},"PeriodicalIF":1.4,"publicationDate":"2026-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13583614/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148992216","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Impacts of Outgroup Selection in bPTP Species Delimitation Analyses: a Case Study in Cichlid Fishes of the Genus <i>Australoheros</i> Říčan & Kullander, 2006 (Cichliformes: Cichlidae) from Coastal Basins of Southern South America.","authors":"Rebeca Rosa, Elisabeth Henschel, Edro H N de Ragança, Grazielle F E Gomes, Felipe P Ottoni","doi":"10.6620/ZS.2026.65-27","DOIUrl":"10.6620/ZS.2026.65-27","url":null,"abstract":"<p><p>The goal of this study is a methodological evaluation of the Bayesian Poisson Tree Processes (bPTP) method for species delimitation in the genus <i>Australoheros</i>. We hypothesize that the increase in phylogenetic distance of the outgroup used decreases the number of delimited Operational Taxonomic Units (OTUs). We test the impact of different outgroups, positioned at varying phylogenetic distances from the ingroup, in a dataset extracted from the most recent taxonomic study for <i>Australoheros</i>. Lucena and collaborators validated 17 species, but used a dataset containing identical haplotypes, thus violating an important premise of the bPTP method. We reanalyzed the dataset of this work, but followed the assumptions of the bPTP method. We tested outgroup-distance effects on species delimitation by using seven distinct outgroups from distinct genera, tribes and subfamilies of the Cichlidae, totaling eight <i>COI</i> and eight CYTB matrices. <i>COI</i> analyses delimited between 15 and 9 OTUs; CYTB analyses between 24 and 14, showing consistent OTU reduction as outgroups became more phylogenetically distant. Our results highlight that CYTB delimited a greater number of OTUs, however, this dataset contains a higher number of haplotypes than <i>COI</i>. We consider that the use of phylogenetically distant outgroups may reduce the adequate recovery of OTUs.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"65 ","pages":"e27"},"PeriodicalIF":1.4,"publicationDate":"2026-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13463199/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148724809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A New Species of <i>Cestoplanoida</i> (Platyhelminthes: Polycladida) from Southern Taiwan, with the First Molecular Data for the Genus.","authors":"Shih-Chieh Kuo, Ting-Yu Li, Wei-Ban Jie","doi":"10.6620/ZS.2026.65-26","DOIUrl":"10.6620/ZS.2026.65-26","url":null,"abstract":"<p><p><i>Cestoplanoida</i> Faubel, 1983, a poorly known monotypic genus within Cestoplanidae Lang, 1884, characterized by multiple female copulatory apparatuses, was previously known only from <i>C</i>. <i>polypora</i> (Meyer, 1921). We describe a second species, <i>C</i>. <i>wanlitongensis</i> sp. nov., from the intertidal zone of Pingtung County, southern Taiwan. It resembles <i>C</i>. <i>polypora</i> in external morphology and copulatory apparatuses but differs in having the pharynx in the posterior quarter rather than the posterior third of the body. Histological examination reveals protandrous sequential hermaphroditism and the absence of Lang's vesicle, which is also absent in <i>C</i>. <i>polypora</i> based on a reassessment of its original description. This observation prompts the exclusion of Lang's vesicle from the genus diagnosis. Phylogenetic analyses of partial 28S rDNA sequences tentatively place <i>C</i>. <i>wanlitongensis</i> sp. nov. as sister to <i>Eucestoplana</i> Faubel, 1983, within a strongly supported monophyletic clade representing Cestoplanidae. This study expands the taxonomic and molecular knowledge of <i>Cestoplanoida</i>, revises the generic diagnosis, and contributes to understanding the phylogenetic relationships within Cestoplanidae, providing a framework for future systematic and evolutionary studies.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"65 ","pages":"e26"},"PeriodicalIF":1.4,"publicationDate":"2026-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13347195/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148425740","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biodiversity of Terrestrial Gastropods in Two Urban Ecological Reserves in Argentina.","authors":"Fátima F Brito, Marina Güller, Juan López-Gappa","doi":"10.6620/ZS.2026.65-28","DOIUrl":"10.6620/ZS.2026.65-28","url":null,"abstract":"<p><p>Urban ecological reserves in Buenos Aires city (Argentina) were intended as spaces for outdoor recreation, preservation of natural environments and protection of native species. Reserva Ecológica Costanera Sur (RECS) and Reserva Ecológica Ciudad Universitaria Costanera Norte (RECUCN) are located on the right bank of the Río de la Plata estuary. In view of the repeated appearance of non-native land snails and slugs in Argentina during the last four decades, we wanted to know to what extent the terrestrial gastropod faunas of these two reserves were composed of native or non-native species. As RECS is larger than RECUCN, we also tested the hypothesis that abundance, species richness and diversity would be higher in the former than in the latter. Fifty-two and 25 sites were sampled for terrestrial snails and slugs in RECS and RECUCN, respectively. Land gastropod species richness was similar in RECS (14 species) and RECUCN (12 species). Non-native gastropods were much more diverse and overwhelmingly more abundant than native ones. The terrestrial gastropod fauna is dominated by non-native snails and slugs (98.4% non-native individuals vs. 1.6% native in RECS, 97.5% vs. 2.5% in RECUCN), most of them never previously reported from these reserves. More than 78% of the individuals found in RECUCN belonged to the non-native snail <i>Vallonia pulchella</i>, which was the species that most contributed to the dissimilarity between reserves. This study shows that so far, urban ecological reserves in Buenos Aires city are sites where mainly exotic rather than native terrestrial molluscs are being preserved. The dominance of nonnative species in these urban ecological reserves endorses the pervasive advance of synanthropic species in urban land snail assemblages already documented for other biogeographic regions.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"65 ","pages":"e28"},"PeriodicalIF":1.4,"publicationDate":"2026-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13347196/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148425780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Occurrence of the Genus <i>Marmocandona</i> (Ostracoda, Candoninae) in Italy, with the Description of Two New Species.","authors":"Giampaolo Rossetti, Fabio Stoch, Ilaria Mazzini","doi":"10.6620/ZS.2026.65-16","DOIUrl":"10.6620/ZS.2026.65-16","url":null,"abstract":"<p><p>The genus <i>Marmocandona</i>, established in 2012 to encompass species formerly attributed to the <i>Pseudocandona zschokkei</i> species group, currently includes five subterranean species distributed across the Western Palearctic region. The presence of <i>M. zschokkei</i>, the most widely distributed species and the only one with a documented fossil record in the genus, has previously been reported in Italy, albeit without conclusive evidence. This study substantially enhances the known diversity of <i>Marmocandona</i> through the description of three species from northern Italy: two collected from the hyporheic zone of streams and one from a spring, the latter currently left in open nomenclature. Additionally, the occurrence of <i>M.</i> sp. aff. <i>zschokkei</i> has been documented in a cave in Central Italy. Morphological analyses of these newly described taxa, along with previously recognized species, revealed a combination of plesiomorphic and apomorphic traits in their chaetotaxy. This study also offers preliminary insights into the potential timing and mechanisms underlying the colonization of subterranean habitats by this new species.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"65 ","pages":"e16"},"PeriodicalIF":1.4,"publicationDate":"2026-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13347197/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148425419","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Histological Divergence Underlying Globular Body Shapes in Ornamental Goldfish.","authors":"Kinya G Ota, Gembu Abe, Chen-Yi Wang, Ing-Jia Li, Paul G L Sanchez","doi":"10.6620/ZS.2026.65-29","DOIUrl":"10.6620/ZS.2026.65-29","url":null,"abstract":"<p><p>Body shape diversity in vertebrates reflects a complex interplay between functional demands, environmental constraints, and internal developmental mechanisms. Various environments have promoted diverse morphological adaptations not only under natural but also domesticated conditions. One of the most remarkable examples of artificially induced morphology is found in the domesticated ornamental goldfish (<i>Carassius auratus</i>), which has diversified into numerous strains with strikingly different body shapes through prolonged human selection. In this study, we compared the body shapes of representative goldfish strains: the single-tail common goldfish (wild-type), <i>Ryukin</i>, <i>Oranda</i>, <i>Pearlscale</i>, and <i>Ranchu</i>. Our analysis revealed that the <i>Ryukin</i> and <i>Pearlscale</i> strains exhibit significantly greater body circularity in dorsal view compared to the other strains. Further anatomical and histological analyses showed that <i>Pearlscale</i> goldfish possess a thicker lateral body wall along with increased adipose tissue accumulation and reduced muscle fiber density, unlike <i>Ryukin</i> goldfish. These findings suggest that similar globular body shapes in different goldfish strains have arisen through distinct developmental pathways, exemplifying morphological convergence accompanied by histological divergence. We further discuss adipose accumulation in <i>Pearlscale</i> goldfish in relation to natural examples, providing insight into how function, morphology, and tissue organization may be interlinked in the evolution of globular body shapes.</p>","PeriodicalId":49331,"journal":{"name":"Zoological Studies","volume":"65 ","pages":"e29"},"PeriodicalIF":1.4,"publicationDate":"2026-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13358384/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148438613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}