Journal of Parasitology最新文献

{"title":"TWO NEW SPECIES OF METABENEDENIELLA (MONOGENOIDEA: CAPSALIDAE: BENEDENIINAE) PARASITIZING MARINE SNAPPERS (TELEOSTEI: LUTJANIDAE) IN THE WESTERN PACIFIC OCEAN, WITH NOTES ON THE NOMENCLATURE OF METABENEDENIELLA AND METABENEDENIELLA HOPLOGNATHI.","authors":"Delane C Kritsky","doi":"10.1645/25-26","DOIUrl":"10.1645/25-26","url":null,"abstract":"<p><p>Two new species of Capsalidae (Benedeniinae) are described from snappers (Lutjanidae) occurring in the western Pacific Ocean: Metabenedeniella bracteola n. sp. from the blubberlip snapper, Lutjanus rivulatus, collected off Lizard Island, Queensland, Australia, and Metabenedeniella duplohelix n. sp. from the mangrove red snapper, Lutjanus argentimaculatus, from off Nouméa, New Caledonia. Clarification of the nomenclature of Metabenedeniella and its type species is provided: Metabenedeniella Yamaguti, 1958. represents the valid name of the genus and Metabenedeniella hoplognathi Yamaguti, 1958, its type species. The type species is a junior subjective synonym of Epibdella (Benedenia) hoplognathi Yamaguti, 1942 [now Metabenedeniella hoplognathi (Yamaguti, 1942) Yamaguti, 1963, the valid taxonomic name of the species].</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"571-581"},"PeriodicalIF":1.1,"publicationDate":"2025-08-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144958052","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":"TERRESTRIAL LEECHES, iDNA SURVEYS, AND BEYOND.","authors":"Michael Tessler, Mai Fahmy","doi":"10.1645/24-98","DOIUrl":"10.1645/24-98","url":null,"abstract":"<p><p>Terrestrial leeches have long been famous for their blood-feeding behavior, feeding on humans who venture into wet forests across much of the Indo-Pacific. More recently these leeches have emerged as a tool for detecting vertebrate diversity in conservation studies. Specifically, scientists use DNA from the bloodmeals found in these leeches' digestive tracts to identify mammals, reptiles, amphibians, and birds they have fed on. Although this so-called invertebrate-derived DNA (iDNA) technique has grown in popularity, few resources exist for researchers to gain familiarity with these methods. Most researchers using these methods have a vertebrate conservation focus and therefore may benefit from learning more about the leeches, which are variable and also potentially in need of conservation. For this review, we focused on providing basic information on iDNA best practices and precautions, and on Haemadipsidae leech background and taxonomy. We hope this information empowers more people who live and study in the Indo-Pacific to work with these blood-feeding worms.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"503-515"},"PeriodicalIF":1.1,"publicationDate":"2025-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144957983","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":"SISTERS PARASITIZING SISTERS: ON THE ONCHOBOTHRIIDEAN TAPEWORMS OF HAMMERHEAD AND REQUIEM SHARKS.","authors":"Janine N Caira, Veronica M Bueno, Kirsten Jensen","doi":"10.1645/24-101","DOIUrl":"10.1645/24-101","url":null,"abstract":"<p><p>The onchoproteocephalidean cestodes reported on herein were obtained from requiem (Carcharhinidae) and hammerhead (Sphyrnidae) sharks during fieldwork conducted over the past several decades off Australia, Japan, Malaysian and Indonesian Borneo, Mexico, Mozambique, Senegal, Taiwan, the United States, and Vietnam. Sequence data were generated for the D1-D3 region of the 28S rDNA gene for 36 specimens of 23 species of onchoproteocephalideans. The phylogenetic tree resulting from a Maximum Likelihood analysis revealed 3 subclades consistent with major morphological and host differences among included taxa. One subclade consisted of species of Triloculatum, which have bothridia with 3 subloculi, basal prongs on their hooks that are at least half as long as the axial and abaxial prongs, and a uterus that extends essentially the length of the proglottid. These species parasitize requiem sharks. Another subclade consisted of a subset of species currently assigned to Phoreiobothrium, all of which came from hammerhead sharks. These species have bothridia with 5-11 subloculi, basal prongs on their hooks that are less than half as long as the axial and abaxial prongs or are entirely absent, and a uterus that extends only to the level of the terminal genitalia. The final subclade consisted of species of Phoreiobothrium that have bothridia with 8 or more subloculi, basal prongs on their hooks that are more than half as long as the axial and abaxial prongs, and a uterus that extends much of the length of the proglottid, all of which parasitize requiem sharks. Sphyrnacestus n. gen. is erected for species in the second subclade, and the diagnoses of Phoreiobothrium and Triloculatum are emended. Four new species of Sphyrnacestus n. gen. are described, and the 5 species from hammerhead sharks currently assigned to Phoreiobothrium that are consistent with the morphology of members of the second subclade are transferred to the new genus. Six new species of Phoreiobothrium are also described. Evidence of 16 undescribed species of Phoreiobothrium and 1 undescribed species of Triloculatum is presented. The family Phoreiobothriidae is resurrected for the 3 genera, which all possess bothridia with tri- or bi-pronged hooks and subloculi. Members of this family are predicted to be found in other species of Carcharhinidae and Sphyrnidae. Furthermore, we predict they will not be found to parasitize members of other families of carcharhiniform sharks because phoreiobothriids appear to be restricted to sharks that possess the scroll type rather than the conicospiral type of spiral intestine.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"532-570"},"PeriodicalIF":1.1,"publicationDate":"2025-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144958047","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":"PATHOLOGY AND MOLECULAR IDENTIFICATION OF DEVELOPING HENNEGUYA SPP. ACTINOSPORES WITHIN THE INTESTINAL EPITHELIUM OF DERO DIGITATA DURING AN OUTBREAK OF PROLIFERATIVE GILL DISEASE IN A COMMERCIAL CATFISH POND.","authors":"Justin M Stilwell, Alvin C Camus, Cynthia C Ware, Ambika Tiwari, Charles M Walker, Charles C Mischke, David J Wise, Matt J Griffin","doi":"10.1645/24-153","DOIUrl":"10.1645/24-153","url":null,"abstract":"<p><strong>Abstract: </strong>Dero digitata, a freshwater oligochaete worm found worldwide, serves as the definitive host for the myxozoan Henneguya ictaluri, the cause of proliferative gill disease (PGD) in ictalurid catfish. The study objectives were to describe pathologic changes associated with developing actinospores within D. digitata from a commercial catfish pond during an active PGD outbreak. Specific in situ hybridization probes identified H. ictaluri, Henneguya exilis, and Raabeia-type TGR 2014 actinospore development in pure infections associated with intestinal epithelial hypertrophy, hyperplasia, and vacuolation. Results support findings from other myxozoans demonstrating clonal expansion of myxozoan populations occurs through asexual reproduction of the oligochaete host.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"526-531"},"PeriodicalIF":1.1,"publicationDate":"2025-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144958028","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":"SARCOCYSTIS INFECTIONS IN RIVER OTTER (LONTRA CANADENSIS) IN MICHIGAN.","authors":"J P Dubey, A Gupta, K Kothavale, R Calero-Bernal, M L García-Gil, S R Cotey, R C Scimeca, M V Reichard, B M Rosenthal","doi":"10.1645/25-25","DOIUrl":"10.1645/25-25","url":null,"abstract":"<p><strong>Abstract: </strong>Sarcocystis infections are common in the muscles of herbivores but were, until recently, considered relatively rare in carnivores. Little is known of sarcocysts in the muscles of river otters in the United States. In a previous epidemiologic study of Toxoplasma gondii infections in North American river otters (Lontra canadensis) from Michigan in the 2018 and 2019 harvest season, Sarcocystis DNA was found in 34 (27.4%) of 124 otter muscles. Tongues from these 34 PCR-positive samples were further examined here for Sarcocystis species. An additional batch of frozen 62 samples collected at the end of the season was also tested for Sarcocystis herein. Morphologically, sarcocysts were studied in 23 otters (13 of 34 PCR-positive samples from the first batch and 10 of 62 samples of batch 2) in compression smears and paraffin-embedded histologic sections stained with hematoxylin and eosin. Morphologically, at least 2 different kinds of sarcocysts were identified, 1 with a smooth sarcocyst wall and the second with villar protrusions. By transmission electron microscopy, sarcocysts from 1 otter were similar to Sarcocystis caninum. Morphologically, sarcocysts from the river otter were different from the European otter (Lutra lutra). Sequencing amplification products from 18S rRNA, 28S rRNA, and cox1 genes, suggested S. caninum-like, Sarcocystis svanai-like, and Sarcocystis sp. We detected a third, potentially undescribed species, in 3 otters. Genetic markers for conclusive differentiation of Sarcocystis spp. from mustelids should be developed. The samples in the present study had degraded; better preserved samples are needed for further morphologic studies. This is the first report of S. caninum-like, S. svanai-like, and Sarcocystis sp. in the river otter in the United States.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"516-525"},"PeriodicalIF":1.1,"publicationDate":"2025-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144958036","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":"MENINGOENCEPHALITIS IN STRANDED SMOOTH DOGFISH (MUSTELUS CANIS) INFECTED BY PHILASTERIDES DICENTRARCHI (PHILASTERIDA: PHILASTERIDAE) IN THE NORTHWESTERN ATLANTIC OCEAN.","authors":"Steven P Ksepka, Alisa L Newton, Stephen A Bullard","doi":"10.1645/24-147","DOIUrl":"10.1645/24-147","url":null,"abstract":"<p><p>During August through September 2018, strandings and mortalities of smooth dogfish (Mustelus canis [Mitchill, 1815 [Carcharhiniformes: Triakidae]) occurred on Brighton Beach and Coney Island Beach (Brooklyn, New York). Each of the 8 smooth dogfish examined grossly exhibited hemorrhagic meninges, turbid and pink to red cerebrospinal fluid, and soft and friable olfactory lobes. Wet mounts of the cerebrospinal fluid and brain showed intense infection by scuticociliates in each smooth dogfish. Histopathologic examination of the infected brain revealed intensity-dependent necrotizing meningoencephalitis. We identified the scuticociliate as Philasterides dicentrarchiDragesco, Dragesco, Coste, Gasc, Romestand, Raymond, and Bouix, 1995 (Philasterida: Philasteridae). Small-subunit ribosomal deoxyribonucleic acid (SSU rDNA) sequences (604 base pairs) generated from our specimens were identical (100% nucleotide similarity) to morphologically validated GenBank sequences identified as P. dicentrarchi (JX914665). The 18S phylogenetic analysis revealed that all of the GenBank sequences identified as \"Miamiensis avidus,\" except for the type culture sequence KX357144 (which, as per the International Code for Zoological Nomenclature, objectively comprises Miamiensis avidusThompson and Moewus, 1964sensu stricto), represent P. dicentrarchi. Hence, mortalities of leopard sharks (Triakis semifasciata Girard, 1855 [Carcharniformes: Triakidae]) and of zebra sharks (Stegostoma tigrinum [Forster, 1781] [Orectolobiformes: Stegostomatidae]) in the Northeast Pacific Ocean represent infections by P. dicentrarchi, which have been misidentified as M. avidus previously, and that no evidence exists of M. avidus infecting an elasmobranch. We also provide a comprehensive list of scuticociliates reported to infect fishes and host species infected worldwide.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"479-488"},"PeriodicalIF":1.1,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144637351","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":"HAPLOTYPE DIVERSITY IN ENDOSYMBIOTIC BACTERIA FOLLOWING A HOST SWITCH BY PARASITIC LICE.","authors":"Bret M Boyd, Niyomi House, Ariel C Toloza, David L Reed","doi":"10.1645/24-148","DOIUrl":"10.1645/24-148","url":null,"abstract":"<p><p>The sucking lice (Anoplura: Psocodea: Insecta) parasitize mammals, exclusively consuming blood, which does not contain sufficient quantities of B vitamins to support louse development. Lice are dependent on maternally inherited endosymbiotic bacteria, which can synthesize B vitamins and make them available to the louse. Although most louse species parasitize 1 mammal species, lice occasionally colonize a different mammal species. Despite endosymbiotic bacteria being essential for louse development, little is known about the impact, if any, of a louse colonizing a new mammal species on the louse's endosymbiotic bacteria. To address this knowledge gap, we sought to examine genomic diversity in maternally inherited and host-beneficial endosymbiotic bacteria in sucking lice following the likely colonization of a new host. Here, we examined the genomes of endosymbiotic bacteria, Candidatus Riesia pediculicola, from the human head louse, Pediculus humanus. Pediculus humanus (and their endosymbiotic bacteria) are found on humans and South American primate species. The association of P. humanus with humans predates the appearance of modern humans; however, P. humanus appears to have colonized South American primates more recently (likely following the arrival of humans in South America). We examined the genome of Candidatus Riesia from P. humanus isolated from humans (Homo sapiens) and South American black howler monkeys (Alouatta caraya). Here, we find that endosymbiont diversity in lice collected from black howler monkeys included one-half of all known haplogroups described from lice collected from humans. Furthermore, the endosymbiont haplotypes identified from lice on the black howler monkeys reflect the haplotype diversity of endosymbionts present in lice parasitizing humans in the same geographic region. It is not known if the genetic diversity in the endosymbionts of P. humanus parasitizing the black howler monkey is the result of the ongoing movement of lice from humans to black howler monkeys or from a single host switch involving a genetically diverse population of endosymbionts.</p>","PeriodicalId":16659,"journal":{"name":"Journal of Parasitology","volume":"111 4","pages":"412-418"},"PeriodicalIF":1.1,"publicationDate":"2025-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144528406","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":"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}