During an ichthyoparasitological survey in 2017-2019, six species of acanthocephalans were found among Taiwan's freshwater (Cypriniformes: Xenocyprididae, Cyprinidae) and marine fishes (Scombriformes: Scombridae, Trichiuridae; Anabantiformes: Channidae; Carangaria/misc: Latidae): Micracanthorhynchina dakusuiensis (Harada, 1938), Rhadinorhynchus laterospinosus Amin, Heckmann et Ha, 2011, Pallisentis rexus Wongkham et Whitfield, 1999, Longicollum sp., Bolbosoma vasculosum (Rudolphi, 1819), and one new species, Micracanthorynchina brevelemniscus sp. n. All species are morphologically characterised and illustrated using light and scanning electron microscopy. The finding of R. laterospinosus, P. rexus and B. vasculosum is the first record for these species in Taiwan. Micracanthorhynchina brevelemniscus is similar to Micracanthorhynchina motomurai (Harada, 1935) and M. dakusuiensis in proboscis armature but differs from M. motomurai by larger eggs (53-59 × 15-16 μm vs 40 × 16 μm) and by the number of cement glands (6 vs 4) and from M. dakusuiensis by shorter body length (2.2-2.9 mm vs 4.0 mm in males and 2.9-4.1 mm vs 7.6 mm in females), by the location of the organs of the male reproductive system (from level of the posterior third of the proboscis receptacle in M. brevelemniscus vs in the posterior half of the trunk in M. dakusuiensis), and by length of lemnisci (lemnisci shorter than the proboscis receptacle vs lemnisci longer than the proboscis receptacle). Phylogenetic analyses of almost complete 18S rRNA gene revealed paraphyly of the family Rhadinorhynchidae suggested in previous studies. Micracanthorhynchina dakusuiensis and M. brevelemniscus formed a strongly supported cluster, which formed the earliest diverging branch to the rest of the rhadinorhynchids and transvenids.

• MeSH
• Acanthocephala * anatomie a histologie   MeSH
• fylogeneze MeSH
• helmintózy zvířat * epidemiologie   MeSH
• máloostní * MeSH
• nemoci ryb * epidemiologie   MeSH
• Perciformes * MeSH
• ryby MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Taiwan MeSH

Acanthocephalans are obligate endoparasites characterised by the presence of a proboscis with hooks, which are used to adhere and perforate the intestinal wall of their hosts. Individuals of Echinorhynchus salobrensis Machado Filho, 1948 have been reported parasitising the piranhas Serrasalmus maculatus Kner and Serrasalmus marginatus Valenciennes in the upper Paraná River floodplain. Serrasalmus marginatus is considered non-native at this site, and its establishment occurred after the closure of the Itaipu Hydroelectric, which flooded a natural geographic barrier that separated two ecoregions in the Paraná River. Since they are phylogenetically close and have similar biological and ecological characteristics competition for resources caused the non-native species to become dominant over the native one. Considering the specificity of species of Echinorhynchus Zoega, 1776 in serrasalmids, we evaluated the distribution of E. salobrensis along the gastrointestinal tract of S. maculatus and S. marginatus from the upper Paraná River floodplain. All parasites indices of E. salobrensis were higher in the invasive host S. marginatus when compared to the native S. maculatus. There were no significant interaction effects between host species and sex, and host species and/or sex in the presence of the parasite. When we evaluated the effect of E. salobrensis parasitism on the different gut regions and accessory organs, total abundance was significant in the stomach and caecum organs, and in the first and second regions of the intestine. None of the analytical approaches tested showed an effect of the sex of the host or the sex of the parasite on the presence and abundance of the parasite in the gastrointestinal tract. Studies on acanthocephalan parasitism in fish in Brazil focus on fish farm. The fact that two species of selvage carnivorous fish present high rates of acanthocephalan parasitism, added to the fact that most studies with this group are on farmed fish fed with feed, only emphasise the need for continuity in studies of acanthocephalans in the parasitology of aquatic organisms.

• MeSH
• Acanthocephala * MeSH
• Characiformes * MeSH
• lidé MeSH
• paraziti * MeSH
• řeky MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Brazílie MeSH

Illiosentis Van Cleave et Lincicome, 1939 initially included two species: Illiosentis furcatus Van Cleave et Lincicome, 1939 found in the West Atlantic from Cape Cod in Massachusetts, USA to northern Argentina and Illiosentis cetratus Van Cleave, 1945 with restricted distribution in the Pacific coast of southern California. We are reporting I. furcatus from Peru for the first time and describe a population of I. cetratus from the California corbina, Menticirrhus undulatus (Girard), from southern California. The proboscis hook formula was 14 longitudinal rows for I. furcatus of 18-23 hooks each compared to 16 rows of 19-24 hooks each reported by Van Cleave (1945). We complete the inadequate description of I. cetratus with new information on sexual differentiation in the length of the trunk, dorsal vs. ventral hooks, hook roots, trunk spines, two types of anterior recurved rooted hooks vs. posterior rootless straight hooks, measurements of dorsal and ventral hooks and spines, shape of hook roots, terminal position of the female gonopore, and of position of the cephalic ganglion at the anterior margin of the trunk. We also include new details of the reproductive system in both sexes including Saefftigen's pouch and cement gland ducts. We present new SEM and light microscope images. The Energy Dispersive X-ray analysis (EDXA) shows a high level of sulfur in anterior, middle and posterior hooks in various hook sites, as well as spectra of hook tips with a higher relative concentration of sulfur compared to other hook sites. For the placement of I. cetratus, phylogenetic analysis of sequences of three molecular markers, 18S, 28S rRNA and mitochondrial cox 1 genes, was performed with other related available sequences. The resulting analysis illustrated that I. cetratus was nested within a separate clade along with species of two genera, Dentitruncus truttae Sinzar, 1955 and Neotegorhynchus cyprini Lisitsyna, Xi, Orosová, Barčák et Oros, 2022 represented our species of Illiosentis separate from species of Tegorhynchus Van Cleave, 1921 (as also according to the morphology) with which the Illiosentis species were previously synonymised.

• MeSH
• Acanthocephala * anatomie a histologie   MeSH
• fylogeneze MeSH
• helmintózy zvířat * epidemiologie   MeSH
• nemoci ryb * epidemiologie   MeSH
• Perciformes * MeSH
• síra MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Peru MeSH

Strange oceanographic events such as El Niño and La Niña may have indirect effects on the local transmission processes of intestinal parasites due to the reduction or increase in populations of potential intermediate or definitive hosts. A total of 713 individuals of Lutjanus inermis (Peters) were collected over an 8-year period (October 2015 to July 2022) from Acapulco Bay, Mexico. Parasite communities in L. inermis were quantified and analysed to determine if they experienced interannual variations in species composition and structure as a result of local biotic and abiotic factors influenced by oceanographic events, such as El Niño-Southern Oscillation (ENSO), or La Niña, the cool phase of the ENSO climate pattern. Twenty-six taxa of metazoan parasites were recovered and identified: two Monogenea, eight Digenea, two Acanthocephala, four Nematoda, one Cestoda, seven Copepoda, and two Isopoda. Species richness at the component community level (8 to 17 species) was similar to reported richness in other species of Lutjanus Bloch. Parasite communities of L. inermis exhibited high inter-annual variation in the abundance of component species of parasite. However, the species richness and diversity were fairly stable over time. Climatic episodes of El Niño and La Niña probably generated notable changes in the structure of local food webs, thus indirectly influencing the transmission rates of intestinal parasite species. Changes in species composition and community structure of parasites possibly were due to variations in feeding behaviour during the events and differences in the host body size.

• MeSH
• Acanthocephala * MeSH
• ENSO MeSH
• hlístice * MeSH
• lidé MeSH
• paraziti * MeSH
• Perciformes * parazitologie   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Specimens of Neoechinorhynchus (Neoechinorhynchus) poonchensis sp. n. are described from Schizothorax richardsonii (Gray) in the Poonch River, Jammu and Kashmir. Specimens are thick-walled with dissimilar dorsal and ventral para-receptacle structures, anteriorly manubriated hooks, two giant nuclei in each lemniscus and many subcutaneousy. The lemnisci barely overlap the larger anterior testis, the cement gland has eight giant nuclei, and the seminal vesicle is large with thin walls. The vagina is unremarkable but the long uterus is made up of four specialised regions. Neoechinorhynchus rigidus (Van Cleave, 1928), resembles N. poonchensis sp. n. It is distinguished from N. poonchensis sp. n. by having smaller trunk, proboscis, and male reproductive structures, equal testes, unequal lemnisci with three giant nuclei each, and much larger anterior proboscis hook (130 μm in males) than that originally described by Van Cleave (1928) (70 μm in a female). Anterior hook length alone is sufficient to conclude that the N. rigidus of Datta (1937) is not the same species as the N. rigidus of Van Cleave (1928). Van Cleave's (1928) species remains valid and that of Datta (1937) is considered a different species named Neoechinorhynchus pseudorigidus sp. n., herein. Micropores of N. poonchensis sp. n. have variable distribution in different trunk regions and the Energy Dispersive X-ray analysis demonstrated higher levels of sulfur and lower levels of calcium and phosphorus. Sequences of the 18S rDNA gene from nuclear DNA, and cytochrome c oxidase subunit I (cox1) from mitochondrial DNA of N. poonchensis sp. n. were amplified and aligned with other sequences available on GenBank. Maximum likelihood (ML) and Bayesian inference (BI) analyses inferred for 18S rDNA and cox1 showed that N. poonchensis sp. n. was nested in a separate clade.

• MeSH
• Acanthocephala * MeSH
• Bayesova věta MeSH
• Cyprinidae * MeSH
• helmintózy zvířat * MeSH
• nemoci ryb * MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Adult specimens of Corynosoma australe Johnston, 1937 were recorded from the intestines of California sea lions, Zalophus californianus (Lesson), from Baja California Peninsula, Mexico, whereas larval forms were collected from two fish species on the Argentinian coast. Adult specimens of C. australe were morphologically characterized by having a cylindrical proboscis with 18-20 rows of 12-14 hooks per row and a cylindrical trunk expanded anteriorly into a disk with tiny, triangular spines spreading almost to three quarters of the hind-trunk in males and to the posterior body end in females. The aim of this study was to explore the genetic diversity and systematic position of C. australe distributed in the Americas. Newly generated sequences of the mitochondrial cytochrome c oxidase subunit 1 (cox 1) gene were compared with sequences available from GenBank. Phylogenetic analyses performed with the cox 1 dataset using maximum likelihood and Bayesian inference showed that the 11 new sequences of C. australe recovered from the California sea lion in northern Mexico plus the six sequences from Argentinian seashores formed a clade with other sequences of specimens previously identified as C. australe. The intraspecific genetic divergence among the isolates was very low, ranging from 1 to 1.7%, and in combination with the phylogenetic trees confirmed that the isolates belonged to the same species. The cox 1 haplotype network inferred with 27 sequences revealed 18 haplotypes divided into two clusters clearly separated from each other by 5 substitutions. The first cluster corresponded to specimens from the Northern Hemisphere (United States of America and Mexico), and the second corresponded to specimens from the Southern Hemisphere (Argentina and Brazil). The current evidence suggests that C. australe has an amphitemperate distribution and is associated mainly with otariids with secondary and independent colonization events to other mammals and the Magellanic penguin in the Southern Hemisphere.

• MeSH
• Acanthocephala anatomie a histologie   klasifikace   genetika   růst a vývoj   MeSH
• fylogeografie MeSH
• genetická variace * MeSH
• helmintózy zvířat parazitologie   MeSH
• lachtani rodu Arctocephalus a Callorhinus * MeSH
• larva anatomie a histologie   klasifikace   genetika   růst a vývoj   MeSH
• mikroskopie elektronová rastrovací veterinární   MeSH
• respirační komplex IV MeSH
• sekvenční analýza DNA veterinární   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Argentina MeSH
• Brazílie MeSH
• Mexiko MeSH
• Spojené státy americké MeSH

Morphological characteristics of the acanthocephalan Polymorphus minutus (Goeze, 1782), which was collected from the duck Anas platyrhynchos Linnaeus in the Czech Republic, are described. The mitochondrial (mt) genome of P. minutus was sequenced, with a total length of 14,149 bp, comprising 36 genes including 12 protein coding genes (PCGs), 22 transfer RNA (tRNA) genes and two ribosomal RNA genes (rrnL and rrnS). This genome is similar to the mt genomes of other syndermatan species. All these genes were encoded on the same DNA strand and in the same orientation. The overall nucleotide composition of the P. minutus mt genome was 38.2% T, 27.3% G, 26.2% A, and 8.3% C. The amino acid sequences of 12 PCGs for mt genomes of 28 platyzoans, including P. minutus, were used for phylogenetic analysis, and the resulting topology recovers P. minutus as sister to Southwellina hispida (Van Cleave, 1925), and the two taxa form a sister clade to Centrorhynchus aluconis (Müller, 1780) and Plagiorhynchus transversus (Rudolphi, 1819), which are all species in the Palaeacanthocephala, thus supporting the monophyly of this class.

• MeSH
• Acanthocephala anatomie a histologie   genetika   MeSH
• fylogeneze MeSH
• genom mitochondriální * MeSH
• genom u helmintů * MeSH
• helmintózy zvířat parazitologie   MeSH
• kachny * MeSH
• nemoci ptáků parazitologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH

PURPOSE: The Antarctic dragonfish, Parachaenichthys charcoti is a notothenioid teleost fish endemic to the Southern Ocean surrounding Antarctica. It is a relatively rare fish species; therefore, published data on the parasite communities of P. charcoti are limited. The present study was performed on the Ukrainian Antarctic Station "Akademik Vernadsky", Argentine Islands, West Antarctica and the purpose was to examine the species diversity of the parasites of P. charcoti and to identify the parameters of helminth infection and helminth component community. METHODS: Fifteen specimens of P. charcoti were caught at a depth of 10-30 m and examined using standard parasitological techniques. All helminths (6251 specimens) were collected manually, fixed in 70% ethanol and identified based on their morphology. RESULTS: All examined specimens of P. charcoti were found to be infected with helminths; each fish harboured 10-20 helminth species (mean 13.2; median 13) and 237-804 helminth specimens (mean 417; median 401). Twenty-seven helminth species were found, including nine species of trematodes, 4 of cestodes, 4 of nematodes and 10 of acanthocephalans. P. charcoti is the definitive host for 11 out of 27 helminth species recorded. In the helminth component community, the diversity indices were 2.03 (Shannon's index) and 0.79 (Simpson's index); Pielou evenness index was 0.61, and Berger-Parker dominance index was 0.38. CONCLUSIONS: Our results indicate a high species diversity and complex structure of the helminth community in Antarctic dragonfish P. charcoti in the Argentine Islands.

• MeSH
• Acanthocephala * MeSH
• cizopasní červi * MeSH
• helmintózy zvířat * epidemiologie   MeSH
• ostrovy MeSH
• Perciformes * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Antarktida MeSH
• ostrovy MeSH

In the present study, we analyzed the morphology of three genetic types of the bird-infecting acanthocephalan Polymorphus cf. minutus (PspT1, PspT2, PspT3), mainly based on the cystacanth-stage obtained from amphipods (Gammarus fossarum, Gammarus pulex, Gammarus roeselii, Echinogammarus spp.). Males and females were pooled as there was no considerable difference between the sexes concerning the hook measurements. Additionally, we conducted a laboratory infection of one domestic duck for each Polymorphus type, to compare their performance and localization in this host species, and to obtain adult specimens for morphological comparison. The recovery rate from the ducks 4 weeks after infection was 16% for PspT1, 23.8% for PspT2, and 25% for PspT3. The adult worms were gravid, and the females contained mature eggs. Hook size did not differ considerably between cystacanths and adults of the respective type. The three Polymorphus types could be distinguished based on the cystacanth stage by a linear discriminant analysis that included hook measurements, proboscis length, proboscis width, and number of longitudinal hook rows and hooks per row. Furthermore, PspT3 was more different from PspT1 and PspT2 than the latter types from each other. Mainly the number of longitudinal hook rows differed in PspT3 from the existing descriptions of P. minutus (mainly 14 vs. mainly 16 rows). Potentially, PspT3 could be a non-indigenous parasite that was introduced with G. roeselii and that adapted to use the indigenous G. pulex as a host, while PspT2 might have been introduced to central Europe together with Echinogammarus spp.

• MeSH
• Acanthocephala anatomie a histologie   klasifikace   izolace a purifikace   MeSH
• Amphipoda parazitologie   MeSH
• buněčná diferenciace MeSH
• helmintózy zvířat parazitologie   patologie   MeSH
• interakce hostitele a parazita MeSH
• kachny parazitologie   MeSH
• ptáci MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Geografické názvy
• Evropa MeSH

Current data on reproductive biology and population dynamics of the acanthocephalans are scarce mainly in regions from the tropical Pacific. An analysis was done to identify possible factors that influence variation in infection levels of the acanthocephalan Pseudoleptorhynchoides lamothei Salgado-Maldonado, 1976 in its final host, the blue sea catfish Ariopsis guatemalensis (Günther, 1864), and describe its main reproductive traits. A total of 1,094 A. guatemalensis were collected from Tres Palos Lagoon from August 2014 to December 2015. Prevalence of P. lamothei varied from 1.47% to 38.33%, and mean abundance from 0.03 to 4.44 helminths per examined host. In female P. lamothei relative fecundity increased with total length. Temporal variations in P. lamothei infection levels were attributed mainly to changes in host feeding and reproductive behaviour in response to local environmental factors as climatic season, and variations in water temperature.

• MeSH
• Acanthocephala fyziologie   MeSH
• helmintózy zvířat epidemiologie   parazitologie   MeSH
• nemoci ryb epidemiologie   parazitologie   MeSH
• roční období MeSH
• rozmnožování * MeSH
• sumci * MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Mexiko MeSH