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1.
Zootaxa ; 5397(3): 301-341, 2024 Jan 05.
Article in English | MEDLINE | ID: mdl-38221200

ABSTRACT

A parasite-host, host-parasite and distribution-based checklist of helminths found in bats (Chiroptera) of North America north of Mexico is presented. The parasite-host checklist includes a total of 93 species (including records without a species identification) of helminth parasites reported in the literature from 30 species of bats. These include 54 trematodes, 11 cestodes, and 28 nematodes. Each helminth species is listed under its most current accepted name, with all known synonyms, distribution by state/province, and references for each geographic location. Lists of helminths reported from individual species of bats as well as states of the United States and provinces/territories of Canada are also provided. The following new combinations are proposed: Paralecithodendrium alaskensis (Neiland, 1962) n. comb. for Prosthodendrium alaskensis Neiland, 1962; Paralecthodendrium longiforme (Bhalerao, 1926) n. comb. for Lecithodendrium longiforme Bhalerao, 1926; and Paralecithodendrium singularium (Byrd & Macy, 1942) n. comb. for Prosthodendrium singularium Byrd & Macy, 1942. The state of knowledge of helminths of bats in North America is briefly discussed.


Subject(s)
Chiroptera , Helminths , Parasites , Trematoda , Animals , Chiroptera/parasitology , Mexico , North America
2.
J Parasitol ; 109(6): 550-558, 2023 12 01.
Article in English | MEDLINE | ID: mdl-38018747

ABSTRACT

Digenean trematodes in the strigeid genus Nematostrigea are parasites of various birds, most often ospreys (Pandion haliaetus). Nematostrigea currently contains 2 species, Nematostrigea serpens and Nematostigea hepatica. Nematostrigea serpens is divided into 2 subspecies: N. serpens serpens from the Palearctic and Indomalayan realms and N. serpens annulata from the Nearctic realm. In the present work, we studied the type material of N. serpens annulata and collected new specimens from an osprey in Wisconsin close to the type locality. The original description and illustration of N. serpens annulata were incomplete. Herein we provide a detailed redescription and new illustrations of N. serpens annulata on the basis of the type material as well as newly collected and sequenced specimens. Nematostrigea serpens annulata has a distinct tegumental thickening near the mid-length of the genital cone, which is absent in its congeners. Partial sequences of the large ribosomal subunit (28S) DNA and cytochrome c oxidase subunit 1 (COI) mitochondrial DNA gene sequences were generated from our specimens of N. serpens annulata. Comparisons with previously published sequences of N. serpens serpens from the Palearctic demonstrated 2.2% difference in 28S and 3.7% in COI. On the basis of morphological and molecular comparisons, we elevate N. serpens annulata to species status and recognize it as Nematostrigea annulata Dubois and Rausch, 1948.


Subject(s)
Falconiformes , Trematoda , Animals , Falconiformes/parasitology , Birds/genetics , North America , DNA, Mitochondrial , Phylogeny
3.
Zool J Linn Soc ; 199(2): 533-552, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37795176

ABSTRACT

Members of several genera in the digenean superfamily Microphalloidea, namely Renschetrema, Rohdetrema, Cryptotropa, Cephalouterina and Pseudocryptotropa, are characterized by an unusual dorsal position of the genital atrium. In the absence of phylogenetic data, their systematic position has been unstable. In the most recent taxonomic revision of the Microphalloidea, they were housed in three different families. We studied the morphology and obtained DNA sequences of several microphallolideans with a dorsal genital pore, collected from vertebrates in Southeast Asia and South America. We used sequences of the nuclear 28S gene to infer a superfamily-level phylogeny and sequences of the mitochondrial cox1 gene for family-level phylogeny and species-level comparisons. Based on the combination of molecular phylogenetic data and morphological features, we restore the Cryptotropidae and synonymize the Renschetrematidae with the Cryptotropidae. We erect new genera Paracryptotropagen. nov. and Armadoatriumgen. nov., provide amended diagnoses of the Cryptotropidae and Renschetrema and provide keys to the identification of genera within the family. We resurrect the genus Novetrema, previously synonymized with Pseudocryptotropa, and remove Renschetrema indicum from Renschetrema. We describe four new species from lizards in Vietnam and birds in the Philippines and Peru. The unique morphological features and unusually broad host associations and geographical distributions of cryptotropids are discussed.

4.
J Parasitol ; 109(5): 464-479, 2023 10 01.
Article in English | MEDLINE | ID: mdl-37713534

ABSTRACT

The northern cottonmouth, Agkistrodon piscivorus (Lacépède, 1789) (Viperidae: Crotalinae), occurs in the southeastern United States and is one of the few semiaquatic vipers in the world. Three proteocephalid tapeworms of the genus OphiotaeniaLa Rue, 1911 (Cestoda), have been described from this venomous snake. A critical evaluation of type specimens and tapeworms recently collected from A. piscivorus has revealed that only 2 species, Ophiotaenia marenzelleri (Barrois, 1898) and Ophiotaenia grandisLa Rue, 1911 (new synonym Ophiotaenia agkistrodontis [Harwood, 1933]), are specific parasites of this crotaline viper; both species are redescribed here. Ophiotaenia grandis was originally described from a mixture of 2 species: 'true' O. grandis, which is indistinguishable from O. agkistrodontis described 22 yr later and thus considered to be a junior synonym of O. grandis, and O. marenzelleri. Ophiotaenia marenzelleri, also reported from the pygmy rattlesnake, Sistrurus miliarius (Linnaeus, 1766), is a larger tapeworm with a massive scolex, a large cirrus sac, a very large, annular vaginal sphincter near the equatorial gonopore, and an oval, 3-layered embryophore surrounded by a nearly square hyaline outer membrane. Ophiotaenia grandis is much smaller and more slender and has a narrower scolex, a smaller cirrus sac and vaginal sphincter, a 2-layered embryophore, and a distinctly pre-equatorial gonopore. In addition to O. marenzelleri and O. grandis, other Ophiotaenia species typical of semiaquatic snakes (Colubridae: Natricinae) may be present in the northern cottonmouth, which serves only as a postcyclic or occasional host. There is also a tabular summary of 18 species of Ophiotaenia from semiaquatic snakes worldwide, with information on their hosts, distribution, and taxonomically important characters, including key measurements.


Subject(s)
Agkistrodon , Cestoda , Female , Animals , Peritoneal Cavity , Southeastern United States
5.
Folia Parasitol (Praha) ; 702023 Apr 12.
Article in English | MEDLINE | ID: mdl-37114799

ABSTRACT

Proteocephalid tapeworms of frogs of the family Ranidae ('true' frogs) are reviewed with emphasis on their species diversity, host specificity and geographical distribution. New molecular data (nuclear lsrDNA and mitochondrial COI sequences) are presented for tapeworms of four species of ranid frogs in North America, including the poorly known Ophiotaenia saphena Osler, 1931 of Rana clamitans Latreille and R. catesbeiana (Shaw), which is redescribed using new material from Arkansas, USA. Tapeworms of R. sphenocephala (Cope) and R. pipiens Schreber, the latter previously identified as O. saphena, represent another, putative new species, but are not formally described due to insufficient available material. Proteocephalus papuensis Bursey, Goldberg et Kraus, 2008 from Sylvirana supragrisea (Menzies) is transferred to Ophiotaenia La Rue, 1911 as a new combination. After a critical review of the literature, only nine nominal species of Ophiotaenia are recognised as valid, which is in contrast to the large number of ranid frogs (> 440 spp.). The reasons for this striking disparity are briefly discussed, and a key based on morphology is presented for the identification of all species of Ophiotaenia from the Ranidae. Molecular data are available for only two taxa from North America that form a monophyletic group. The relationships among tapeworms of ranid frogs occurring in other zoogeographical regions are not yet known. The taxonomic status of Batrachotaenia Rudin, 1917, which was erected to accommodate proteocephalids from amphibians, is also discussed. To facilitate future studies, a tabulated summary of all 32 species of proteocephalids belonging to three genera reported from amphibians (frogs and salamanders) is presented, with information on their hosts, distribution, and taxonomically important characters, including key measurements.


Subject(s)
Cestoda , Cestode Infections , Animals , Cestode Infections/epidemiology , Cestode Infections/veterinary , Ranidae , North America
6.
PLoS One ; 18(3): e0279268, 2023.
Article in English | MEDLINE | ID: mdl-36867609

ABSTRACT

Echinostomatid digeneans belonging to the genus Rhopalias are intestinal trematodes found mainly in opossums in the New World. The genus comprises seven species, but their life cycles and intermediate hosts have been unknown until now. During our long-term study carried out in freshwater habitats within the state of Minas Gerais, Southeast Brazil, echinostomatid cercariae lacking collar spines were found in planorbid snails Biomphalaria glabrata, Biomphalaria straminea, Drepanotrema lucidum and Gundlachia ticaga in six different batches of snail samples collected between 2010 and 2019. Morphologically, the larvae reported herein are morphologically consistent with each other and characterized by the presence of 2-3 large ovoid or spherical corpuscles in each main duct of the excretory system, resembling to Cercaria macrogranulosa previously described from the same region of Brazil. Partial sequences of the ITS (ITS1-5.8S-ITS2) region and 28S gene of the nuclear ribosomal RNA operon, and partial sequences of mitochondrial nad1 and cox1 genes were obtained and compared with the data available for members of the family Echinostomatidae. Nuclear markers indicate that all samples of cercariae evaluated in the present study can be assigned to Rhopalias, but distinct from North American isolates of Rhopalias macracanthus, Rhopalias coronatus and Rhopalias oochi (divergence 0.2-1.2% in 28S and 0.8-4.7% in ITS). The lack of differences verified in both 28S and ITS in 5 out 6 studied samples suggested that they belong to the same species. However, nad1 sequences revealed that our cercariae correspond to three distinct species of Rhopalias (interspecific divergence: 7.7-9.9%), named here as Rhopalias sp. 1, found in B. straminea and G. ticaga, Rhopalias sp. 2 found in B. glabrata and D. lucidum, and Rhopalias sp. 3 also found in D. lucidum. They also differ by 10.8-17.2% from a North American isolate of R. macracanthus sequenced in this study. The cox1 sequences obtained for Rhopalias sp. 1 and Rhopalias sp. 2 (but not Rhopalias sp. 3) reveal that they are distinct from North American isolates of R. macracanthus (genetic divergence 16.3-16.5% and 15.6-15.7%, respectively), R. coronatus (9.2-9.3% and 9.3-9.5%) and Rhopalias oochi (9.0% and 9.5-10.1%). Encysted metacercariae with general morphology similar to that of the body of cercariae were found in tadpoles of Rhinella sp. from the same stream where snails harbored Rhopalias sp. 2, suggesting that the amphibians could act as second intermediate hosts of species of Rhopalias. Data obtained provide the first insights into the life cycle of this unusual echinostomatid genus.


Subject(s)
Biomphalaria , Echinostomatidae , Parasites , Trematoda , Animals , Opossums , Base Sequence , Brazil , Life Cycle Stages , Larva , Cercaria
7.
Acta Parasitol ; 68(1): 159-171, 2023 Mar.
Article in English | MEDLINE | ID: mdl-36456776

ABSTRACT

PURPOSE: The Diplostomidae is a globally distributed family of digeneans that parasitize a wide variety of tetrapod definitive hosts. Recent molecular phylogenetic studies have revealed unknown diplostomid diversity in avian hosts throughout the New World. Herein, we provide descriptions of a novel genus of diplostomids with two new species. METHODS: Two species of diplostomids belonging to the new genus were collected from anhinga birds in Mississippi (USA) and Brazil. Partial nuclear 28S ribosomal and mitochondrial cox1 genes were sequenced. Ribosomal data were used for phylogenetic inference. RESULTS: Both species of Anhingatrema n. gen. were positioned in a 100% supported, monophyletic clade in the phylogenetic tree. The molecular phylogenetic position and a combination of morphological features (e.g., presence of pseudosuckers, testes shape and orientation) supported erection of the new genus. Anhingatrema overstreeti n. sp. and Anhingatrema cararai n. sp. are morphologically similar, but differ in size of and ratios associated with pseudosuckers. The two species differ by 2% of 28S sequences and 13.8% of cox1 sequences. Comparison of DNA sequences revealed that Diplostomidae gen. sp. in GenBank (MZ314151) is conspecific with An. overstreeti n. sp. CONCLUSION: Anhingatrema n. gen. is the sixth genus of diplostomids known from anhingas worldwide. Anhingatrema cararai n. sp. is the first diplostomid to be reported from anhingas in South America. Combined with previous studies, the molecular phylogenies revealed at least two host switches to anhingas from other birds during the evolutionary history of the Diplostomidae.


Subject(s)
Trematoda , Animals , Phylogeny , Genes, Mitochondrial , Birds , Brazil
8.
J Parasitol ; 108(5): 453-466, 2022 09 01.
Article in English | MEDLINE | ID: mdl-36223170

ABSTRACT

The Diplostomidae Poirier, 1886 is a large family of digeneans within the superfamily Diplostomoidea Poirier, 1886. Members of the family are distributed worldwide and parasitize a diversity of tetrapod definitive hosts. Notably, only 2 mature diplostomids are known from crocodilians and both are suggested to be accidental infections. In this study, we use morphological and molecular data to describe Neofibricola n. gen. from a Nile crocodile Crocodylus niloticus collected in South Africa. We provide a description of adults and metacercariae of the type species, Neofibricola smiti n. sp., and metacercariae of a likely congeneric species. We generated partial 28S and internal transcribed spacer region ribosomal deoxyribonucleic acid (DNA) and cytochrome c oxidase 1 subunit mitochondrial DNA for both species and utilized the newly generated 28S sequences to examine phylogenetic affinities of these new taxa. In addition, we provide a new key to diplostomid genera, considering the substantial systematic changes and newly erected genera since the previously published key to diplostomid genera.


Subject(s)
Alligators and Crocodiles , Trematoda , Trematode Infections , Animals , DNA, Mitochondrial/genetics , Electron Transport Complex IV/genetics , Phylogeny , South Africa/epidemiology , Trematode Infections/epidemiology , Trematode Infections/veterinary
9.
Zool J Linn Soc ; 196(1): 124-136, 2022 Sep.
Article in English | MEDLINE | ID: mdl-36051981

ABSTRACT

Alaria, Didelphodiplostomum and Pharyngostomoides are among genera of diplostomid digeneans known to parasitize mammalian definitive hosts. Despite numerous recent molecular phylogenetic studies of diplostomids, limited DNA sequence data is available from diplostomids parasitic in mammals. Herein, we provide the first 28S rDNA and cox1 mtDNA sequences from morphologically identified, adult specimens of Didelphodiplostomum and Pharyngostomoides. Newly generated 28S sequences were used to infer the phylogenetic interrelationships of these two genera among other major lineages of diplostomoideans. The phylogeny based on 28S and a review of morphology clearly suggests that Pharyngostomoides should be considered a junior synonym of Alaria, while Didelphodiplostomum should be considered a junior synonym of Tylodelphys. Pharyngostomoides procyonis (type species), Pharyngostomoides adenocephala and Pharyngostomoides dasyuri were transferred into Alaria as Alaria procyonis comb. nov., Alaria adenocephala comb. nov. and Alaria dasyuri comb. nov.; Didelphodiplostomum variabile (type species) and Didelphodiplostomum nunezae were transferred into Tylodelphys as Tylodelphys variabilis comb. nov. and Tylodelphys nunezae comb. nov. In addition, Alaria ovalis comb. nov. (formerly included in Pharyngostomoides) was restored and transferred into Alaria based on a morphological study of well-fixed, adult specimens and the comparison of cox1 DNA sequences among Alaria spp. The diplostomid genus Parallelorchis was restored based on review of morphology.

10.
Syst Parasitol ; 99(5): 637-646, 2022 10.
Article in English | MEDLINE | ID: mdl-35788491

ABSTRACT

Renschetrematidae is a very small family of digeneans parasitic in bats in southern and Southeast Asia. According to the original descriptions and the latest revision, its representatives are characterized by the presence of several unusual characters. Among them are the dorsal position of the genital pores, separate male and female genital pores, and the presence of an accessory sac (stylet pouch) associated with terminal genitalia and containing a stylet-like structure. Prior to our study, the phylogenetic relationships of the Renschetrematidae were unknown and DNA sequence data were absent from any of its representatives. In this work, we present the description of a new species of Renschetrema from bats in the Philippines. We also evaluate the phylogenetic affinities of the Renschetrematidae using newly obtained partial sequences of the 28S rRNA gene from Renschetrema specimens collected in the Philippines and Southeast China. The new species differs from previously described species by the position and orientations of the stylet pouch, presence of accessory spines around genital atrium, position of gonads, body shape and relative size of pharynx and oral sucker. Our phylogenetic analysis supports the status of the Renschetrematidae as an independent family within the superfamily Microphalloidea. In the phylogenetic tree, the Renschetrematidae appeared as an independent family-level lineage, basal to the remaining taxa within the Microphalloidea. Detailed examination of our specimens revealed significant errors in the current diagnoses of the genus Renschetrema and the Renschetrematidae. Amended diagnoses of the genus and the family are provided.


Subject(s)
Trematoda , Animals , Philippines , Phylogeny , RNA, Ribosomal, 28S/genetics , Species Specificity , Trematoda/genetics
11.
Pathogens ; 11(7)2022 Jul 05.
Article in English | MEDLINE | ID: mdl-35890014

ABSTRACT

Schistosomatidae Stiles and Hassall 1898 is a medically significant family of digenetic trematodes (Trematoda: Digenea), members of which infect mammals or birds as definitive hosts and aquatic or amphibious gastropods as intermediate hosts. Currently, there are 17 named genera, for many of which evolutionary interrelationships remain unresolved. The lack of a resolved phylogeny has encumbered our understanding of schistosomatid evolution, specifically patterns of host-use and the role of host-switching in diversification. Here, we used targeted sequence capture of ultra-conserved elements (UCEs) from representatives of 13 of the 17 named genera and 11 undescribed lineages that are presumed to represent either novel genera or species to generate a phylogenomic dataset for the estimation of schistosomatid interrelationships. This study represents the largest phylogenetic effort within the Schistosomatidae in both the number of loci and breadth of taxon sampling. We present a near-comprehensive family-level phylogeny providing resolution to several clades of long-standing uncertainty within Schistosomatidae, including resolution for the placement of the North American mammalian schistosomes, implying a second separate capture of mammalian hosts. Additionally, we present evidence for the placement of Macrobilharzia at the base of the Schistosoma + Bivitellobilharzia radiation. Patterns of definitive and intermediate host use and a strong role for intermediate host-switching are discussed relative to schistosomatid diversification.

12.
Parasitol Int ; 89: 102575, 2022 Aug.
Article in English | MEDLINE | ID: mdl-35292369

ABSTRACT

Ochoterenatrema is a small genus of lecithodendriid digeneans that includes six species parasitic in Neotropical bats in North and South America. Members of this genus are characterized by the presence of a pseudogonotyl formed by thickened tegument on the left side of the ventral sucker. We examined morphology of specimens belonging to five species of Ochoterenatrema from Brazil, Ecuador and the USA and describe two new Ochoterenatrema spp. (Ochoterenatrema sphaerula n. sp. and Ochoterenatrema gracilis n. sp.). These new species are readily differentiated from their congeners by a combination of morphological characters, including the distribution of vitelline follicles and the body shape. We have provided the first DNA sequences for Ochoterenatrema. Newly generated partial nuclear 28S rDNA and mitochondrial cox1 gene sequences were used to differentiate among species and study the phylogenetic affinities of Ochoterenatrema spp., including one of the new species, O. gracilis n. sp., as well as Ochoterenatrema diminutum, Ochoterenatrema fraternum and Ochoterenatrema cf. labda. The phylogeny of the Microphalloidea based on 28S had well-supported topology, particularly at the family level. The Ochoterenatrema clade was strongly supported; however, the internal topology of the clade was weakly supported. Comparison of sequences revealed 0.4-1.3% interspecific divergence in 28S and 9.1-19.7% interspecific divergence in cox1 among Ochoterenatrema spp. We hypothesize that extremely diverse fauna of bats in South and Central America harbors multiple undescribed species of Ochoterenatrema. Several lecithodendriid genera from bats and other hosts are yet to be included in future molecular phylogenetic analyses to test the monophyly of this extremely diverse digenean family and analyze evolutionary affinities of its constituent taxa.


Subject(s)
Chiroptera , Trematoda , Trematode Infections , Animals , Brazil , Chiroptera/parasitology , Phylogeny , RNA, Ribosomal, 28S/genetics , Trematode Infections/parasitology , Trematode Infections/veterinary
13.
Parasitol Res ; 121(3): 933-944, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35106652

ABSTRACT

Philophthalmus is a cosmopolitan genus of digeneans that includes ocular parasites of birds and mammals. Despite broad distribution and veterinary importance of these digeneans, there are still gaps in knowledge about their diversity and biology, especially in South America. Herein, we conducted morphological, life cycle, and molecular studies of megalurous cercariae found in aquatic gastropod molluscs Aylacostoma chloroticum and A. tuberculatum collected in the São Francisco River, Brazil. Adult parasites reared experimentally in the eyes of chicks are described here as Philophthalmus aylacostoma n. sp. The new species differs from its congeners known in the Americas by a combination of traits, including the sucker width ratio, the oral sucker to pharynx width ratio, egg size, and the type of vitellarium in adult forms. The new species is morphologically closest to Philophthalmus megalurus, from which it differs by the smaller body and larger eggs, as well as by the measurements of cercariae and the family of snails that act as the intermediate host. Molecular phylogenetic analysis based on 28S rDNA and comparison of cox1 sequences confirm that P. aylacostoma n. sp. is distinct from four previously sequenced named species of the genus. Moreover, cox1 sequences revealed conspecificity of our specimens with an isolate of Philophthalmus sp. previously reported, also in thiarid snails, in Paraná River, Brazil. The interspecific divergence in cox1 between the new species and other species with sequences available for comparison varied between 12 and 15%.


Subject(s)
Gastropoda , Trematoda , Trematode Infections , Animals , Brazil , Chickens/parasitology , Gastropoda/parasitology , Life Cycle Stages , Phylogeny , Trematode Infections/parasitology , Trematode Infections/veterinary
14.
Parasitol Res ; 121(5): 1407-1417, 2022 May.
Article in English | MEDLINE | ID: mdl-35106653

ABSTRACT

Avian haemosporidians from the genera Plasmodium and Haemoproteus are vector transmitted parasites. A growing body of evidence suggests that variation in their prevalence within avian communities is correlated with a variety of avian ecological traits. Here, we examine the relationship between infection probability and diversity of haemosporidian lineages and avian host ecological traits (average body mass, foraging stratum, migratory behavior, and nest type). We used molecular methods to detect haemosporidian parasites in blood samples from 642 individual birds of 149 species surveyed at four localities in the Brazilian Pantanal. Based on cytochrome b sequences, we recovered 28 lineages of Plasmodium and 17 of Haemoproteus from 31 infected avian species. Variation in lineage diversity among bird species was not explained by avian ecological traits. Prevalence was heterogenous across avian hosts. Bird species that forage near the ground were less likely to be infected by Haemoproteus, whereas birds that build open cup nests were more likely infected by Haemoproteus. Furthermore, birds foraging in multiple strata were more likely to be infected by Plasmodium. Two other ecological traits, often related to host resistance (body mass and migratory behavior), did not predict infection probability among birds sampled in the Pantanal. Our results suggest that avian host traits are less important determinants of haemosporidian diversity in Pantanal than in other regions, but reinforces that host attributes, related to vector exposure, are to some extent important in modulating infection probability within an avian host assemblage.


Subject(s)
Bird Diseases , Haemosporida , Parasites , Plasmodium , Protozoan Infections, Animal , Animals , Bird Diseases/epidemiology , Bird Diseases/parasitology , Birds/parasitology , Phylogeny , Plasmodium/genetics , Prevalence , Protozoan Infections, Animal/epidemiology
15.
Parasitology ; 149(4): 542-554, 2022 04.
Article in English | MEDLINE | ID: mdl-35042575

ABSTRACT

Fibricola and Neodiplostomum are diplostomid genera with very similar morphology that are currently separated based on their definitive hosts. Fibricola spp. are normally found in mammals, while Neodiplostomum spp. typically parasitize birds. Previously, no DNA sequence data was available for any member of Fibricola. We generated nuclear ribosomal and mtDNA sequences of Fibricola cratera (type-species), Fibricola lucidum and 6 species of Neodiplostomum. DNA sequences were used to examine phylogenetic interrelationships among Fibricola and Neodiplostomum and re-evaluate their systematics. Molecular phylogenies and morphological study suggest that Fibricola should be considered a junior synonym of Neodiplostomum. Therefore, we synonymize the two genera and transfer all members of Fibricola into Neodiplostomum. Specimens morphologically identified as Neodiplostomum cratera belonged to 3 distinct phylogenetic clades based on mitochondrial data. One of those clades also included sequences of specimens identified morphologically as Neodiplostomum lucidum. Further study is necessary to resolve the situation regarding the morphology of N. cratera. Our results demonstrated that some DNA sequences of N. americanum available in GenBank originate from misidentified Neodiplostomum banghami. Molecular phylogentic data revealed at least 2 independent host-switching events between avian and mammalian hosts in the evolutionary history of Neodiplostomum; however, the directionality of these host-switching events remains unclear.


Subject(s)
Platyhelminths , Trematoda , Animals , Birds , DNA, Mitochondrial/genetics , Mammals , Phylogeny , Platyhelminths/genetics
16.
Int J Parasitol ; 52(1): 47-63, 2022 01.
Article in English | MEDLINE | ID: mdl-34371018

ABSTRACT

The Diplostomidae Poirier, 1886 is a large, globally distributed family of digeneans parasitic in intestines of their definitive hosts. Diplostomum and Tylodelphys spp. are broadly distributed, commonly reported, and the most often sequenced diplostomid genera. The majority of published DNA sequences from these genera originated from larval stages only, which typically cannot be identified to the species level based on morphology alone. We generated partial large ribosomal subunit (28S) rRNA and cytochrome c oxidase subunit 1 (cox1) mtDNA gene sequences from 14 species/species-level lineages of Diplostomum, six species/species-level lineages of Tylodelphys, two species/species-level lineages of Austrodiplostomum, one species previously assigned to Paralaria, two species/species-level lineages of Dolichorchis and one unknown diplostomid. Our DNA sequences of 11 species/species-level lineages of Diplostomum (all identified to species), four species/species-level lineages of Tylodelphys (all identified to species), Austrodiplostomum compactum, Paralaria alarioides and Dolichorchis lacombeensis originated from adult specimens. 28S sequences were used for phylogenetic inference to demonstrate the position of Paralaria alarioides and Dolichorchis spp. within the Diplostomoidea and study the interrelationships of Diplostomum, Tylodelphys and Austrodiplostomum. Our results demonstrate that two diplostomids from the North American river otter (P. alarioides and a likely undescribed taxon) belong within Diplostomum. Further, our results demonstrate the non-monophyly of Tylodelphys due to the position of Austrodiplostomum spp., based on our phylogenetic analyses and morphology. Furthermore, the results of phylogenetic analysis of 28S confirmed the status of Dolichorchis as a separate genus. The phylogenies suggest multiple definitive host-switching events (birds to otters and among major avian groups) and a New World origin of Diplostomum and Tylodelphys spp. Our DNA sequences from adult digeneans revealed identities of 10 previously published lineages of Diplostomum and Tylodelphys, which were previously identified to genus only. The novel DNA data from this work provide opportunities for future comparisons of larval diplostomines collected in ecological studies.


Subject(s)
Trematoda , Animals , Birds , DNA, Mitochondrial/genetics , Larva , Phylogeny , Species Specificity
17.
Syst Biodivers ; 20(1): 1-18, 2022.
Article in English | MEDLINE | ID: mdl-36970113

ABSTRACT

The Proterodiplostomidae Dubois, 1936 is a family of digeneans within the superfamily Diplostomoidea Poirier, 1886. Members of the family are distributed mostly in the tropics and subtropics, primarily in crocodilians, although some species are known from other reptiles. Despite their broad geographical distribution, the knowledge of proterodiplostomid diversity remains limited, mostly because a number of potential host species and regions of the world have not been sufficiently explored for these parasites. In this study, we use morphological and molecular data to describe four new genera (Afroproterodiplostomum gen. nov., Dungalabatrema gen. nov., Australiadiplostomum gen. nov. and Nattererodiplostomum gen. nov.) and five new species (Afroproterodiplostomum ingwenyae sp. nov., Australiadiplostomum blairi sp. nov., Dungalabatrema kostadinovae sp. nov., Dungalabatrema snyderi sp. nov. and Pseudoneodiplostomum angustus sp. nov.) of proterodiplostomids from crocodilians in Australia, South Africa and South America. Nattererodiplostomum gen. nov. has been established upon re-evaluation of the status of Proterodiplostomum medusae (Dubois, 1936) from caimans in Brazil using combined morphological and molecular evidence. Only a few previous studies provided DNA sequence data of proterodiplostomids. We generated partial 28S rDNA and cytochrome c subunit (cox1) mtDNA for three previously undescribed proterodiplostomids collected from Crocodylus spp. in Australia and South Africa. The newly generated 28S sequences were used to examine phylogenetic affinities of these taxa. All three newly sequenced proterodiplostomid species appeared in the phylogenetic tree in a strongly supported monophyletic clade comprising exclusively parasites of Crocodylus.

18.
J Parasitol ; 107(4): 566-574, 2021 07 01.
Article in English | MEDLINE | ID: mdl-34310683

ABSTRACT

Neopsilotrema is a small genus of psilostomid digeneans parasitic in the intestine of birds in the Palearctic and Nearctic. At present, the genus includes 4 species: Neopsilotrema lisitsynae from the Palearctic and Neopsilotrema affine, Neopsilotrema lakotae, and Neopsilotrema marilae from the Nearctic. Herein, we describe a new species, Neopsilotrema itascae n. sp., from lesser scaup Aythya affinis collected in Minnesota. The species can be distinguished from congeners on the basis of the ventral sucker:oral sucker width ratio, body width:length ratio, and cirrus sac size, along with other characters. We generated new 28S ribosomal deoxyribonucleic acid (DNA) and NADH dehydrogenase (ND1) mitochondrial DNA sequence data of a variety of psilostomids from the Palearctic and Nearctic along with sequences of the ribosomal internal transcribed spacer (ITS) region (ITS1 + 5.8S + ITS2) from 3 Neopsilotrema species. The molecular phylogenetic affinities of a variety of psilostomid taxa were studied using 28S sequence data. The 28S sequences of psilostomids demonstrated 1-7.9% intergeneric divergence, whereas the sequences of ND1 had 17.7-34.1% intergeneric divergence. The interspecific divergence among members of Neopsilotrema was somewhat lower (0.2-0.5% in 28S; 0.3-0.4% in ITS; 12-15.7% in ND1). Our comparison of DNA sequences along with morphologic study suggests Holarctic distribution of N. lisitsynae.


Subject(s)
Bird Diseases/parasitology , Ducks/parasitology , Trematoda/classification , Trematode Infections/veterinary , Animals , Base Sequence , Bird Diseases/epidemiology , DNA, Helminth/chemistry , DNA, Ribosomal/genetics , DNA, Ribosomal Spacer/chemistry , Genetic Variation , Minnesota/epidemiology , NADH Dehydrogenase/genetics , Phylogeny , RNA, Helminth/genetics , RNA, Ribosomal, 28S/genetics , RNA, Ribosomal, 5.8S/genetics , Trematoda/anatomy & histology , Trematoda/genetics , Trematoda/isolation & purification , Trematode Infections/epidemiology , Trematode Infections/parasitology
19.
J Parasitol ; 107(3): 455-462, 2021 05 01.
Article in English | MEDLINE | ID: mdl-34086924

ABSTRACT

As presently recognized, Herpetodiplostomum is a small genus of proterodiplostomid digeneans parasitic in crocodilians. Most members of Cheloniodiplostomum, a genus of proterodiplostomids that parasitize chelonians, were originally placed within Herpetodiplostomum. The 2 genera were distinguished based on the presence/absence of papillae on the holdfast organ and anterior extent of vitellarium. Our study of Herpetodiplostomum and Cheloniodiplostomum revealed a lack of consistent morphological differences between the genera. Therefore, we consider Cheloniodiplostomum to be a junior synonym of Herpetodiplostomum. Recent molecular phylogenetic studies included a number of proterodiplostomid taxa; however, DNA sequence data are not available for any Herpetodiplostomum or Cheloniodiplostomum species. Herein, we describe a new Herpetodiplostomum species from Geoffroy's side-necked turtle Phrynops geoffroanus from Mato Grosso State, Brazil. The new species can be distinguished from other Herpetodiplostomum species based on the distribution of vitellarium, level of development of holdfast papillae, and ratio of prosoma:opisthosoma width, among other characters. We provide the first molecular phylogeny of the Proterodiplostomidae that includes a Herpetodiplostomum species. The limited geographic distribution of Herpetodiplostomum spp. within the geographic ranges of caimans suggests a secondary host switching event from crocodilians to chelonian definitive hosts in the evolution of Herpetodiplostomum.


Subject(s)
Trematoda/classification , Trematode Infections/veterinary , Turtles/parasitology , Animals , Bayes Theorem , Brazil/epidemiology , Phylogeny , Trematoda/genetics , Trematoda/isolation & purification , Trematode Infections/epidemiology , Trematode Infections/parasitology
20.
Parasitol Res ; 120(6): 2003-2016, 2021 Jun.
Article in English | MEDLINE | ID: mdl-33860845

ABSTRACT

Anenterotrema is a small genus of dicrocoeliids (Digenea: Dicrocoeliidae) containing 6 species found in Neotropical bats. Members of this genus are characterized by the lack of digestive system organs and, unlike the majority of dicrocoeliids, parasitize the intestine of their definitive hosts. In this study, we have morphologically examined newly collected specimens belonging to four species of Anenterotrema from Brazil, Ecuador, and Panama. Based on the data in original descriptions and our analysis of quality new specimens, we resurrected Anenterotrema freitasi, previously synonymized with A. eduardocaballeroi. We also described a new species of Anenterotrema from Molossus molossus in the Brazilian Amazon. The new species differs from congeners in several morphological features, most prominently in the size and structure of its highly muscular, protuberant ventral sucker. It is also characterized by the lack of the semi-circular thickening of the tegument around the oral sucker typical for some members of the genus. We used partial DNA sequences of the large ribosomal subunit gene (28S) and mitochondrial cytochrome c oxidase subunit 1 gene (cox1) to test the monophyly of Anenterotrema, and study the interrelationships and determine the inter- and intraspecific variation of three Anenterotrema spp. collected from different bat species in Brazil, Ecuador and Panama.


Subject(s)
Chiroptera/parasitology , Dicrocoeliidae/classification , Trematode Infections/veterinary , Animals , Brazil/epidemiology , Dicrocoeliidae/anatomy & histology , Dicrocoeliidae/genetics , Genes, Mitochondrial , Phylogeny , Species Specificity , Trematode Infections/epidemiology , Trematode Infections/parasitology
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