Journal of Parasitology最新文献

{"title":"NEOLEBOURIA MULLINEAUXAE N. SP. (TREMATODA: DIGENEA) AND ANOTHER OPECOELID FROM DEEP-SEA HYDROTHERMAL VENT FIELDS OFF CENTRAL AMERICA AND PAPUA NEW GUINEA, WITH SPECIES KEYS AND A COMPARISON TO MESOBATHYLEBOURIA.","authors":"Lauren N Dykman, Deidric B Davis, Charles K Blend","doi":"10.1645/24-113","DOIUrl":"10.1645/24-113","url":null,"abstract":"<p><p>Neolebouria mullineauxae n. sp. (Digenea: Opecoelidae), exhibiting remarkable morphological variation (i.e., 2 distinctive morphotypes), is described from the intestine of the zoarcid eelpout or pink vent fish, Thermarces cerberus, collected from deep-sea hydrothermal vent fields along the East Pacific Rise (EPR) off the west coast of Central America. It can be distinguished from its congeners by having a unique diagnostic combination of features including a small body and gonads that are smaller relative to body size, a prebifurcal genital pore, a cirrus pouch that extends posteriorly as far as the posterior margin of the ventral sucker while the anterior margin of the latter is either close to or overlaps the intestinal bifurcation, confluent vitelline fields within the posttesticular space, and vitelline follicles and eggs that are not as dense and few to moderate in number, respectively. This report introduces a new family (Zoarcidae) and genus (Thermarces) of fish infected by the genus Neolebouria, a new host record in that this is the first taxonomic description of a digenetic trematode from T. cerberus; a new geographic locality for Neolebouria (sensu stricto)-the East Pacific Ocean off the coast of Central America-and a life cycle of the new species within the hydrothermal vent biome is postulated, including the sporocyst stage which utilizes the glass limpet, Eulepetopsis vitrea, as a first intermediate host. Two immature digeneans (cf. Opecoelidae) are described herein, collected from vent fields off Papua New Guinea, and represent a new host record in that this is the first report of a digenetic trematode from the zoarcid eelpout, Pyrolycus manusanus. Based on molecular analysis of the 28S gene, N. mullineauxae n. sp. was 99.92% (1,218/1,219 base pairs [bp]) similar to Neolebouria georgiensis. It was genetically closer to a previously described vent digenean, Buticulotrema thermichthysi, than to Mesobathylebouria lanceolata, despite the new species sharing morphological characteristics with the genus Mesobathylebouria. The 2 distinctive morphotypes of N. mullineauxae n. sp. were genetically identical in the 28S and ITS2 barcoding regions, supporting their identity as a single species. Given the similarity of N. mullineauxae n. sp. to members of Mesobathylebouria morphologically and ecologically, a thorough comparison of both genera is presented, as well as new keys to species, and a plea offered for a more efficacious diagnostic suite of morphological characters to distinguish both genera.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"451-478"},"PeriodicalIF":1.1,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144637352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"PARAPLEUROGENOIDES (DIGENEA), A NEW GENUS IN PELOPHYLAX BEDRIAGAE (ANURA: RANIDAE) FROM KURDISTAN, IRAN WITH COMMENTS ON THE RELATIONSHIPS WITHIN PLEUROGENIDAE.","authors":"Loghman Maleki, Mastoreh Shahmoradi, Kiavash Golzarianpour","doi":"10.1645/24-102","DOIUrl":"10.1645/24-102","url":null,"abstract":"<p><p>The systematics of the family Pleurogenidae Looss, 1899, has been significantly revised in recent years, with the addition of 7 new genera based on molecular data. Despite these advancements, this family still lacks a definitive morphological synapomorphy. It encompasses genera with considerable morphological diversity, parasitizing a wide range of host groups across the globe. In the present study, we describe Parapleurogenoides n. gen., a new genus within the Pleurogenidae, discovered in the Levant water frog, Pelophylax bedriagae (Camerano, 1882), from the Sanandaj region of western Iran. This new genus is distinguished by its pyriform body shape, vitelline glands with a limited number of follicles, and a Y-shaped excretory vesicle. To investigate its phylogenetic relationships, a dataset of partial 28S rRNA sequences was generated, including all Pleurogenidae species available in GenBank. The phylogenetic analysis reveals that Parapleurogenoides kurdistanensis n. sp. and cercariae from Vietnam form a distinct clade, which is sister to Pleurogenes claviger (Rudolphi, 1819) and Pleurogenoides medians (Olsson, 1876). These clades are classified within Pleurogenidae, a family known for parasitizing amphibians. Moreover, the relationships within Pleurogenidae and the taxonomy of the genus Pleurogenoides Travassos, 1921, are re-evaluated based on morphological traits and the potential inclusion of other species previously assigned to this genus.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"431-440"},"PeriodicalIF":1.1,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144637353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"DESCRIPTION, REDESCRIPTION, AND LIFE CYCLES OF CLOACITREMA KURISI N. SP. AND CLOACITREMA MICHIGANENSIS (TREMATODA: DIGENEA: PHILOPHTHALMIDAE) FROM THE CALIFORNIA HORN SNAIL, CERITHIDEOPSIS CALIFORNICA (GASTROPODA: POTAMIDIDAE).","authors":"Alexandria P Nelson, Daniel C G Metz, Ryan F Hechinger","doi":"10.1645/24-41","DOIUrl":"10.1645/24-41","url":null,"abstract":"<p><p>We describe the parthenita colonies, soldier rediae, reproductive rediae, cercariae, metacercariae, and sexual adults of Cloacitrema michiganensisMcIntosh, 1938 and Cloacitrema kurisi n. sp. using material from natural and experimental infections and molecular-genetic analyses. Cloacitrema kurisi, a \"pseudo-cryptic\" species, was previously pooled with C. michiganensis in research involving the guild of trematodes infecting the California horn snail, Cerithideopsis californica (Haldeman, 1840), as a first intermediate host. Our morphological data suggest that C. kurisi contaminated an earlier description of the C. michiganensis life cycle based on that same snail host. Our descriptions of all life stages use material originating from naturally infected, lab-maintained horn snails from San Diego, California. By repeatedly shedding cercariae from specific, labeled snails, we obtained material for experimental infections, developmental studies, and genetics. In all cases, these data were matched to individual first-intermediate host colonies. These same colonies were finally dissected to describe the morphology, behavior, and demographics of reproductive and soldier rediae. Metacercaria descriptions came from cercariae shed and encysted in the laboratory; we also document a metacercaria developmental time series for each species. We experimentally exposed final host chickens (Gallus gallus domesticus) and ducks (Anas platyrhynchos domesticus) to metacercariae per cloaca; we successfully obtained and described sexual adults only from the chickens. Both cytochrome c oxidase subunit 1 (COI) and 28S phylogenetic analyses corroborated that these are 2 Cloacitrema species. As indicated in its original description, C. michiganensis adults can be readily distinguished from other Cloacitrema species by the combination of their inter-cecal uterus; small, oval pharynx; large, equatorial ventral sucker; and the presence of inter-testicular space. The C. kurisi adult stage can be distinguished from other Cloacitrema species by the combination of its extra-cecal, post-testicular uterus; particularly large, round pharynx; the complete absence of an esophagus; and the presence of inter-testicular space. We use our morphometric data to provide an emended diagnosis for the genus Cloacitrema. There are now 10 formally named species of Cloacitrema, 4 of which have had their first intermediate host stages described.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"393-411"},"PeriodicalIF":1.1,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144528405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A QUARTER CENTURY OF SAMPLING TWO OCEAN BASINS TO DISAMBIGUATE THE IDENTITY OF A MULLET PARASITE, SACCOCOELIOIDES BEAUFORTI (DIGENEA: HAPLOPORIDAE).","authors":"Stephen S Curran, Stephen A Bullard","doi":"10.1645/25-22","DOIUrl":"10.1645/25-22","url":null,"abstract":"<p><p>Saccocoelioides beauforti (Hunter and Thomas, 1961) Overstreet, 1971, an intestinal parasite of flathead grey mullet, Mugil cephalus Linnaeus, was originally described from off North Carolina (northwestern Atlantic Ocean) and purportedly ranges south and west to Louisiana (north-central Gulf of America). We surveyed the parasites of hundreds of flathead grey mullet captured from coastal habitats of Georgia, Alabama, and Mississippi over a 25 yr period, from 1998 through 2023. Examination of whole-mounted specimens of \"S. beaufort\" revealed substantial morphological variation between specimens from off North Carolina to Georgia (Northwestern Atlantic Ocean) with those from off Mississippi and Alabama (north-central Gulf of America), with some overlap in Georgia. We therefore investigated the identities of these 2 groups of parasites that were, until now, accepted as conspecific. Observations of the museum specimens and newly collected specimens, augmented by ITS2 and 28S rRNA gene fragment comparisons, indicated that S. beauforti sensu stricto infects flathead grey mullet along the eastern coast of the United States between North Carolina and Georgia. Furthermore, specimens previously identified as S. beauforti from Georgia (in part), south Florida, and the north-central Gulf of America are conspecific with Saccocoelioides macrospinosusAndrade-Gómez, Sereno-Uribe, and García-Varela, 2019, which was previously thought to infect only the Catemaco molly, Poecilia catemaconis Miller, and the white mullet, Mugil curema Valenciennes, in freshwater and brackish habitats in Veracruz, Mexico. Flathead grey mullet is a new host record for S. macrospinusus. Fish hosts and ranges for S. beauforti sensu stricto and S. macrospinosus overlap in coastal Georgia.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"441-450"},"PeriodicalIF":1.1,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144637348","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FIRST RECORD OF PHYLLOBOTHRIID METACESTODES IN CHIMAERA MONSTROSA (HOLOCEPHALI) AND ONCORHYNCHUS GORBUSCHA (SALMONIDAE): NOVEL INSIGHT INTO LARVAL TOPOGRAPHY AND ULTRASTRUCTURE.","authors":"Larisa G Poddubnaya, Roman Kuchta, Tomáš Scholz","doi":"10.1645/24-136","DOIUrl":"10.1645/24-136","url":null,"abstract":"<p><p>Scanning electron microscopy was used to study the scolex morphology of 3 morphotypes of metacestodes of the order Phyllobothriidea (Cestoda) from the spiral intestine of the North Sea rabbitfish Chimaera monstrosa and the intestine and gall bladder of the pink salmon Oncorhynchus gorbuscha. Transmission electron microscopy allowed a detailed examination of the ultrastructure of the tegument, unicellular gland cells, muscle cells, and calcareous corpuscles of metacestodes of different sizes from chimaeras. Based on our morphological data, we propose that the studied intestinal metacestodes from chimaeras and pink salmon belong to the type XV metacestodes of Jensen and Bullard, possibly related to members of the genus Clistobothrium Dailey and Vogelbein, 1990.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"419-430"},"PeriodicalIF":1.1,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144637350","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A NOVEL HENNEGUYA (MYXOSPOREA) FROM THE GILLS OF GREEN SUNFISH, LEPOMIS CYANELLUS (CENTRARCHIFORMES: CENTRARCHIDAE), FROM THE BLACK RIVER (WHITE RIVER DRAINAGE) OF ARKANSAS.","authors":"Chris T McAllister, Donald G Cloutman, Eric M Leis, Alvin C Camus, Henry W Robison","doi":"10.1645/24-82","DOIUrl":"10.1645/24-82","url":null,"abstract":"<p><p>A new species of genus Henneguya Thélohan, 1892 (Bivalvulida: Myxobolidae) is described from the gills of 2 of 7 (29%) green sunfish, Lepomis cyanellus (Rafinesque) from Coffee Creek of the Black River, White River drainage, Arkansas. Henneguya rafinesquei n. sp. differs from the only other species of Henneguya reported from centrarchids, Henneguya episcleraMinchew and Sleight, 1977, from Lepomis gibbosus (L.), and from Lepomis macrochirus Rafinesque by having a smaller myxospore total length (34.9 [31.3-37.1 μm] vs. 62.6 [49-81] μm). The body and polar capsules of H. rafinesquei n. sp. are pyriform, whereas the body of H. episclera is obovate to elliptical and the polar capsules are elliptoid with a narrow neck. Henneguya rafinesquei n. sp. is genetically most similar to Myxobolus branchiarumKsepka, Rash, and Bullard, 2022 from smallmouth bass, Micropterus dolomieu Lacépède, and Myxobolus lepomisRosser, Baumgartner, Barger, and Griffin, 2017 from dollar sunfish, Lepomis marginatus (Holbrook), but is easily distinguished morphologically by possessing 2 elongate caudal processes that are lacking in the latter 2 species. Phylogenetic analysis of the 1,963-base-pair small-subunit ribosomal ribonucleic acid gene placed H. rafinesquei n. sp. in a clade among other myxozoans that primarily infect centrarchids and comprises only the second species of Henneguya reported from any member of the sunfish family. Although the precise site of development within lamellae could not be determined histologically, a plasmodium with associated epithelial hyperplasia and mild lymphocytic inflammation produced a nodular lesion that displaced adjacent lamellae, altering normal gill morphology.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"496-502"},"PeriodicalIF":1.1,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144698878","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"AMPHIBIAN PARASITES EXHIBIT IDIOSYNCRATIC RELATIONSHIPS WITH SPATIOTEMPORAL ENVIRONMENTAL AND HOST-COMMUNITY VARIATION.","authors":"Kyle D Gustafson, Vasyl V Tkach, Robert A Newman","doi":"10.1645/24-63","DOIUrl":"https://doi.org/10.1645/24-63","url":null,"abstract":"<p><p>Why parasites occur in certain hosts in certain locations has been a long-standing question among ecological and evolutionary parasitologists. Encounter and compatibility filters summarize the likelihood that a host and parasite will physically interact and establish an infection upon contact. Encounter and compatibility filters are not fixed and, among multiple locations, the abiotic environmental characteristics and biotic community composition that contribute to the filters often vary spatially and temporally. Abiotic variation may directly affect hosts or parasites-particularly parasites with 1 or more free-living stages-whereas the local biotic community may dilute or amplify parasite transmission. Unlike directly transmitted parasites, complex-life cycle parasites use multiple hosts, thus having life cycles that, we hypothesize, are highly susceptible to the effects of spatiotemporal environmental variation. We modeled infection probability relationships of endohelminths from post-metamorphic wood frogs (Rana [Lithobates] sylvatica) and northern leopard frogs (Rana pipiens) with wetland characteristics, landscape composition, and the anuran species within the local community. Parasites included complex-life cycle trematodes that use amphibians as definitive hosts (Haematoloechus spp., Glypthelmins quieta) or as intermediate hosts (Alaria sp., Neodiplostomum sp., echinostomatids, and Lechriorchis) and nematodes with direct or indirect life cycles (Cosmocercoides and Oswaldocruzia). Although our results demonstrate that distributions of parasites with complex and direct life cycles are correlated with some abiotic and biotic characteristics of the environment, there were few general trends. Each parasite's distribution had its own unique relationship with wetland, landscape, and amphibian-community variables, and there was overall low predictability for most species. One landscape feature-the number of wetlands within the vicinity of the site of amphibian capture-was commonly included in top models for leopard frogs and could be associated with how definitive hosts (e.g., amphibians, mammals, and birds) and intermediate hosts (e.g., snails and odonates) use the landscape. The amphibian community at any given site also commonly affected infection probabilities, such that the local presence of other species tended to reduce infection probabilities in sampled frogs, lending support to the dilution effect at the landscape level. Our research highlights the need to consider spatiotemporal sampling, environmental variation, and host-community variation when studying parasite prevalence in any given component community.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 3","pages":"262-275"},"PeriodicalIF":1.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144127965","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"NEW SPECIES OF AXINE ABILDGAARD, 1794 (MONOGENOIDEA: AXINIDAE) INFECTING GILL LAMELLAE OF ATLANTIC FLYINGFISH, CHEILOPOGON MELANURUS (VALENCIENNES) (EXOCOETIDAE) IN THE WESTERN ATLANTIC OCEAN WITH PHYLOGENETIC ANALYSIS AND COMMENTS ON THE FEMALE GENITALIA OF AXINE SPP.","authors":"John H Brule, Micah B Warren, William B Driggers, Stephen A Bullard","doi":"10.1645/24-145","DOIUrl":"https://doi.org/10.1645/24-145","url":null,"abstract":"<p><p>We collected specimens of Axine trickyvagina Brule and Bullard n. sp. (Monogenoidea: Axinidae) from the gill lamellae of Atlantic flyingfish, Cheilopogon melanurus (Valenciennes) (Exocoetidae) in the north-central Gulf of America. Specimens of the new species were heat-killed and formalin-fixed for morphology, and others were preserved in 95% EtOH for DNA extraction and sequencing of the 28S gene and ITS1 region. The new species differs from all congeners by the combination of having a long haptor (∼40-50% of the total body length), a male copulatory organ with 10-15 spines, and a genital atrium having bilateral spinous patches each with 18-25 spines. Our study of specimens of the new species, type and voucher specimens representing 8 congeners, and all published accounts of all congeners revealed that the terminal female genitalia of Axine spp. comprises 2 ducts (a multi-chambered vagina that lacks a sclerite plus an accessory duct with a sclerotized nozzle comprising its opening) that open into a common female genital atrium. Descriptions of Axine spp. published from 1794 through 2023 failed to recognize the vaginal duct and accessory duct as distinct components and unanimously misinterpreted the accessory duct's sclerotized nozzle as a \"vaginal spine.\" The phylogenetic analysis inferred from 28S rDNA sequences placed our sequence in a clade of other Mazocraeidea spp. and sister to a nonugen sequence ascribed to Axine japonicaPrice, 1946 (GenBank LC799038). We recovered Axinidae as sister to Heteromicrocotylidae, Heteraxinidae, and Microcotylidae. The present study is the first published description of an axinid from a flyingfish in the western Atlantic Ocean.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 3","pages":"276-286"},"PeriodicalIF":1.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144150741","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"MOLECULAR SURVEY OF HAEMOSPORIDIAN PARASITES IN HAWKS, FALCONS, AND OWLS (ACCIPITRIFORMES, FALCONIFORMES, STRIGIFORMES) FROM MINNESOTA AND NORTH DAKOTA, WITH REMARKS ON THE PHYLOGENETIC RELATIONSHIPS OF HAEMOSPORIDIANS IN NORTH AMERICAN RAPTORS.","authors":"Jeffrey A Bell, Timothy G Driscoll, Tyler J Achatz, Jakson R Martens, Jefferson A Vaughan","doi":"10.1645/25-16","DOIUrl":"https://doi.org/10.1645/25-16","url":null,"abstract":"<p><p>Avian haemosporidians are a diverse group of apicomplexan parasites that are globally distributed and infect almost all avian orders. Haemosporidian surveys of raptors (birds of prey) are underrepresented compared to those of songbirds, perhaps because of the greater difficulty in capturing and handling raptors. In this study, we captured raptors over a 7-yr period from northeastern North Dakota and northwestern Minnesota. Using standard molecular methods, we successfully screened 595 individuals representing 5 species of hawks (Accipitriformes), 3 species of falcons (Falconiformes), and 7 species of owls (Strigiformes). The overall infection prevalence averaged 41.5%, ranging from 31.6% in falcons (n = 38) to 85.7% in owls (n = 14). Thirty-one (12.6%) of the 247 infected raptors were infected concurrently with 2 or more haemosporidian genera. Leucocytozoon was the most common parasite genus identified. A total of 27 haemosporidian lineages were identified composed of 8 Leucocytozoon, 6 Parahaemoproteus, and 13 Plasmodium lineages. Twelve lineages (44%) were novel lineages identified for the first time. Raptor host order showed a significant phylogenetic signal within the tree topology of haemosporidian lineages from North American raptors. A significant effect of host order was also identified in the phylogenetic reconstructions of Haemoproteus, Leucocytozoon, and Parahaemoproteus lineages, with large clades restricted to mostly Accipitriformes and Strigiformes. Similar host specificity was not evident within the Plasmodium phylogeny, with most lineages infecting multiple raptor host orders and some lineages not restricted to raptors. Our results demonstrate that raptors support a unique and diverse community of haemosporidian parasites, many of which are distinct to raptor species. Studying haemosporidians within raptors expands our knowledge of host-parasite evolutionary relationships, species diversity, and cryptic speciation within this ubiquitous group of parasites.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 3","pages":"299-314"},"PeriodicalIF":1.0,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144266462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"THE BROAD FISH TAPEWORMS DIBOTHRIOCEPHALUS SPP., THE SEALWORM PHOCANEMA CATTANI, AND OTHER ENDOHELMINTH PARASITES IN THE RETURNING NONNATIVE CHINOOK SALMON, ONCORHYNCHUS TSHAWYTSCHA, IN THE VALDIVIA RIVER BASIN, CHILE.","authors":"Patricio Torres, Hélène Yera, Alonso Rubilar, Célia Rouges, Victor Leyán, Ricardo Silva","doi":"10.1645/24-71","DOIUrl":"10.1645/24-71","url":null,"abstract":"<p><p>In the present study, we examined nonnative returning Chinook salmon caught between 2018 and 2023 in the Valdivia River basin, Chile, for endohelminth parasites. Zoonotic endohelminths were identified by morphological and molecular methods, based on a multiplex PCR or PCR and sequencing targeting the cytochrome c oxidase gene of diphyllobothriids or Ascaridoidea mitochondrial DNA. A total of 5,350 larvae of helminths were detected in the salmon, with 3.6% corresponding to the cestodes Dibothriocephalus latus and Dibothriocephalus dendriticus, with freshwater life cycles, and 96% to \"Scolex pleuronectis,\" 0.2% to Hepatoxylon trichiuri, 0.1% to Nybelinia sp., and 0.1% to the nematode Phocanema cattani, all with a marine life cycle. All salmon had plerocercoids of Dibothriocephalus spp., with the highest percentage in the peritoneum and intestine. Only D. latus was identified in the muscles of 40% of salmon, with up to 7 larvae per host and a mean density of 0.1 larvae per 200 g. The present results indicate that most (63.6%) of the plerocercoids of Dibothriocephalus spp. can survive during the migration of Chinook salmon to the ocean and their return to freshwater. The sealworm P. cattani was found for the first time in Chinook salmon with a prevalence of 20% in the muscles. \"Scolex pleuronectis\" was abundant in the intestine and pyloric caeca, representing 96% of the identified endohelminths. One-third of the salmon had H. trichiuri in the body cavity, and Nybelinia sp. in the intestine wall. Plerocercoids of Dibothriocephalus spp. were mostly encapsulated and a few free in different organs. Histologically, the free larvae of Dibothriocephalus spp. were associated with an infiltrate of mononuclear and polymorphonuclear cells suggesting damage to their tegument. Larvae of Nybelinia sp. in the muscular layer of the intestine were surrounded by a thin capsule to which they were attached by the tegument; mononuclear and polymorphonuclear cells were observed outside the capsule and in some areas in contact with the larva. Plerocercoids of D. latus and Nybelinia sp. were associated with abundant mast cells in the intestinal wall. The presence of the zoonotic Dibothriocephalus spp. and P. cattani in returning salmon would increase their potential risk of transmission to the human population in the Valdivia River basin area. Similarly, salmon carcasses could facilitate the potential transmission of Dibothriocephalus spp. and P. cattani to wild and domestic mammals and wild birds.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 3","pages":"210-226"},"PeriodicalIF":1.1,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144015310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}