Search

Summary The present study was carried out on 10 frogs, Pelophylax ridibundus (Pallas, 1771), captured near the river Bahlui, Iasi, between April and May, 2019, for the study of digestive helminths and their effect on the digestive tract. Macroscopic examination of the general cavity revealed distension of the small intestine. The sectioning of the intestinal wall revealed a variable number of parasites (1 – 12) with a whitish cylindrical body, anchored in the duodenal mucosa. The morphological study of the parasites confirmed the species as Acantocephalus ranae. The prevalence of the infection was 60 % and the average intensity was 4.83 ± 4.15. Lesions of the small intestine were characterized by catarrhal enteritis, hemorrhagic spots and ulcers on the mucosa, occlusion and obstruction of the intestinal lumen. Histologically, eosinophilic inflammatory infiltrate in the glandular crypts, mucosal and submucosal edema, fibrosis and conjunctival hyperplasia, total mucosal atrophy, were found. The infection with Acanthocephalus ranae in Pelophylax ridibundus caused severe pathological changes, conditioned by the intensity of the infection, aspects revealed for the first time in Romania.

In Vietnam, fisheries play a key role in the national economy. Helminth infections in fish have a major impact on public health and sustainable fish production. A comprehensive summary of the recent knowledge on fish helminths is important to understand the distribution of parasites in the country, and to design effective control measures. Therefore, a systematic review was conducted, collecting available literature published between January 2004 and October 2020. A total of 108 eligible records were retrieved reporting 268 helminth species, among which are digeneans, monogeneans, cestodes, nematodes and acanthocephalans. Some helminths were identified with zoonotic potential, such as, the heterophyids, opisthorchiids, the nematodes Gnathostoma spinigerum, Anisakis sp. and Capillaria spp. and the cestode Hysterothylacium; and with highly pathogenic potential, such as, the monogeneans of Capsalidae, Diplectanidae and Gyrodactylidae, the nematodes Philometra and Camallanidae, the tapeworm Schyzocotyle acheilognathi, the acanthocephalans Neoechinorhynchus and Acanthocephalus. Overall, these studies only covered about nine percent of the more than 2400 fish species occurring in the waters of Vietnam. Considering the expansion of the aquaculture sector as a part of the national economic development strategy, it is important to expand the research to cover the helminth fauna of all fish species, to assess their potential zoonotic and fish health impacts., Graphical abstract Image 1, Highlights • 268 helminth species were reported in 213 fish species occurring in Vietnam. • Reported zoonotic helminths belonged to digeneans, nematodes and cestodes. • Other species included monogeneans, nematodes, cestodes and acanthocephalans.

Human acanthocephaliasis is a zoonotic parasitic infection with acanthocephalan species. Reports documenting human infection with acanthocephalans are relatively rare in the literature. Nonetheless, man has been infected with acanthocephalans since ancient times. Despite their economic and medical significance, acanthocephalans were found to be good indicators of environmental pollution. This review summarizes current knowledge of acanthocephalans as human parasites and their beneficial uses

The features of the nematode and acanthocephalus fauna of Cypriniformes and Siluriformes fish, their distribution in the water bodies of the Syrdarya River midstream were studied. In total, 18 helminth species belonging to the classes Nematoda – (14 species) and Acantocephala – (4) are registered in the region. 7 species we marked for the first time for the region of under consideration.Studies were conducted of different types of water bodies of the Syrdarya river in 2016–2019 years. The collection and study of helminths of fish were carried out by known methods in helminthology and ichthyoparasitology. 1239 copies of Cypriniformes fish belonging to 15 species (Cyprinidae – 12 species, Cobitidae – 3) and 12 specimens of Siluriformes fishes from the families (Siluridae and Clariidae) were researched.According to preliminary data, 18 species of helminths belonging to the class Nematoda (14 species) and to the class Acantocephala (4 species) were found in the studied fish orders in the reservoirs of the region. Significant species diversity is characterized by the class Nematoda. We have registered 14 species belonging to 4 orders. The detachment Trichocephalida Skrjabin et Schulz, 1928 is represented by one species – Capillaria tomentosa Dujardin, 1843, which is noted in most Cypriniformes in the natural and artificial reservoirs of the northeast of Uzbekistan. The greatest species diversity is distinguished by the detachment Spirurida Chitwood, 1933. We noted 8 species. The remaining units are represented by 1–2 species – banal fish parasites. The findings of Dioctophyme renale Goeze, 1782 (larvae) in Cypriniformes in the studied region should be noted.The Acanthocephala class is represented by 4 species: Neoechinorhynchus rutileMüller, 1780, Pomphorhynchus laevis Müller, 1776, Acanthocephalus lucii Müller, 1776 and A. anguillae Müller, 1780. Nematodes are dominant. The results suggest that the most optimal conditions for the functioning of the corresponding helminth communities probably exist in the water bodies of the Syrdarya’s midstream. The abundance of a number of invertebrate groups, the inhabitants of aquatic ecosystems, which are intermediate hosts of parasites, the accumulation of waterbirds and mammals contribute to the irreversible circulation of helminths in aquatic cenoses of the study area. All this requires systematic monitoring of fish helminthiasis in order to develop preventive measures.

The round goby, Neogobius melanostomus, is a Ponto-Caspian fish species currently found in many parts of Europe, including the North Sea riverine deltas. The objective of this study was to examine the parasite community of fish caught in the lower Elbe (Süderelbe – tidal zone; Geesthacht – non-tidal) in Germany and compare it with published data from the upper Elbe (Ústí nad Labem) in the Czech Republic. Twelve parasite taxa were recorded in the lower Elbe, six in the Süderelbe and nine near the city of Geesthacht. Süderelbe fish were mainly infected with Angullicola crassus larvae, while gobies from Geesthacht – with glochidia and sporadically occurring Pomporhynchus laevis, and the opposite situation was observed at Ústí nad Labem. It appears that a large tidal weir at Geesthacht significantly contributes to the division of the round goby population, with the Geesthacht parasite community being more similar to that at Ústí nad Labem than the one from the Süderelbe, thus increasing the likelihood that shipping from Hamburg was the introduction vector to Ústí nad Labem. We also recorded Acanthocephalus rhinensis in the Elbe for the first time, and in a new host – the round goby. Thus, round gobies may represent a new vector for the introduction of this parasite along the Elbe.

Acanthocephalans have multi-host life cycles that include arthropods as intermediate hosts and vertebrates as definitive hosts. Eggs are dispersed into the habitat from definitive hosts and in some species eggs possess fibrils, which have been proposed to facilitate transmission to intermediate hosts. We examined the potential role of fibrils in transmission of the acanthocephalan Acanthocephalus dirus to its intermediate host Caecidotea intermedius, a stream-dwelling isopod. We identify three properties of fibrils that could favor transmission. First, there was a slow rate of fibril release, which was dependent on the actions of stream microorganisms. Second, eggs with fibrils were more likely to adhere to the substrate than those without fibrils. Third, in feeding trials, isopods exposed to eggs with fibrils had a higher infection prevalence than isopods exposed to eggs without fibrils. These properties could favor transmission by increasing the likelihood that eggs sink to the sediment occupied by their target hosts before adhering to items on the substrate (e.g., leaves) and by increasing recruitment after the eggs have been consumed.

Background Twelve species of Filisoma Van Cleave, 1928 are recognized parasitizing tropical and subtropical fish. Four of these species were described from kyphosid fish and it has been suggested that a co-speciation may have occurred among species of Kyphosus Lacepède, 1801 and Filisoma, which could provide valuable information about the evolution history of this host–parasite system. Purpose During a survey of the helminth fauna of Kyphosus sectatrix (Linnaeus, 1758) and Kyphosus incisor (Cuvier, 1831) (Kyphosidae Jordan, 1887) off Rio de Janeiro coast, a new species of Filisoma was found and is described herein based on morphological, genetic, and ultrastructural data. Methods Fish were obtained off Rio de Janeiro coast, Brazil. The parasites found in the intestine were measured and drawings were made with a drawing tube. Type specimens were deposited at the Helminthological Collection of Oswaldo Cruz Institute (CHIOC). The ultrastructure was studied using scanning electron microscope. The genetic analysis included the study of the partial sequences of 18S, ITS1, 5.8S and 28S rDNA, and the mitochondrial cytochrome c oxidase 1 gene (cox 1), with phylogenetic reconstructions based on the maximum likelihood analysis. Results Filisoma caudata n. sp. is characterized by a proboscis with 16‒18 longitudinal rows of 38‒45 hooks each. Hooks are uniform in shape dorsoventrally, gradually decreasing in size towards the base of the proboscis. Anterior hooks are 30‒45 μ long, middle hooks 30‒35 μ long and 5 basal transversal hooks 20‒30 μ long. The new species is differentiated from the closest species Filisoma filiformis Weaver and Smales, 2013 by the size and distribution of hooks, apart from having a subterminal vulva and a curved posterior trunk end (tail) measuring 500‒1,000 long. Phylogenetic analysis based on 18S, 28S rDNA and mtDNA-cox1 markers grouped the new species with Filisoma bucerium Van Cleave, 1940 and Filisoma rizalinum Tubangui and Masiluñgan, 1946 showing a close relationship between these species of Cavisomidae Meyer, 1932 and Echinorhynchidae Cobbold, 1879; the latter represented by species of Acanthocephalus Koelreuther, 1771. The new species can be differentiated from others on morphological and molecular basis. A key to the 13 species of Filisoma Van Cleave, 1928 is provided. Conclusion Filisoma caudata n. sp. is described herein based on morphological, genetic, and ultrastructural data. The topologies of obtained phylogenies suggest that species of Echinorhynchidae should be reevaluated since the family is considered paraphyletic in all analyses conducted.

It is reported the case of an adult titi monkey (Plecturocebus oenante) parasitized with Prosthenorchis elegans, which died at the end of December 2019. The animal was in a wildlife rescue centre located on the banks of the Shilcayo Quebrada, the entrance gate of the national park "Cordillera Escalera", in San Martín, Peru. The animal, living in semi-captivity, did not show clinical signs, but it collapsed from a height of 5 m. At necropsy, abdominal exudate, perforation at the level of the small intestine, congestion of blood vessels and mesenteric lymphadenopathy, nodulations in the intestinal wall and a severe infection of white and round parasites were evidenced. The coproparasitological examination revealed characteristic eggs of the genus Prosthenorchis and the analysis of the adult parasite revealed the cranial hooks and characteristic structures of the species Prosthenorchis elegans, a parasite found in neotropical primates. This case is reported not as an accidental necropsy finding, but one which cause of death was as a consequence of septic shock due to a generalized peritonitis caused by a severe parasitic infection of this Acantocephalus that generated an intestinal perforation., Se reporta el caso de un mono tocón adulto, macho (Plecturocebus oenante) parasitado con Prosthenorchis elegans, fallecido a fines de diciembre de 2019, en un centro de custodia de fauna silvestre ubicado a orillas de la Quebrada Shilcayo, puerta de entrada del Área de Conservación Regional “Cordillera Escalera”, San Martín, Perú. El animal, en semi-cautividad, no presentó signos clínicos, pero se desplomó desde una altura de 5 m. A la necropsia, se evidenció exudado abdominal, perforación a nivel del intestino delgado, congestión de vasos sanguíneos y linfoadenopatía mesentérica, nodulaciones en pared intestinal y una severa infección de parásitos blanquecinos y redondos. Al examen coproparasitológico, se evidenciaron huevos característicos del género Prosthenorchis y al análisis del parásito adulto se observaron las ganchos craneales y estructuras características de la especie Prosthenorchis elegans, parásito encontrado en primates neotropicales. Se reporta este caso, no como un hallazgo accidental de necropsia, sino cuya causa de muerte fue a consecuencia de un shock séptico, consecuente de la peritonitis generalizada causado por una severa infección parasitaria de este acantocéfalo que generó una perforación a nivel intestinal.

Quince ejemplares del sapo bufonido Rhinella icterica (Spix, 1824), 7 machos y 8 hembras, colectados en elmunicipio de Botucatu, Estado de São Paulo, Brasil, desde marzo del 2002 hasta enero del 2003, fueronanalizados en busca de helmintos parásitos. Todos los sapos estaban infectadas con al menos un parásito(prevalencia global = 100%). Cinco especies de helmintos fueron encontradas, entre ellas cuatro especies de nematodos, Rhabdias fuelleborniTravassos, 1926, Oswaldocruzia subauricularis (Rudolphi, 1819), gen. sp. no identificada Cosmocercidae Travassos, 1925 y larvas de Physaloptera Rudolphi, 1819, y una especieacantocéfalo, Acanthocephalus saopaulensis Smales, 2007. Rhabdias fuelleborni y A. saopaulensis fueronlas especies más abundantes. Aexcepción de las larvas de Physalopteridae, todos los helmintos presentaron una alta prevalencia (> 70%). Todas las especies de helmintos presentaron una tendencia hacia un patrón más agregado de distribución en los hospederos muestreados.

Neoechinorhynchus cylindratus Van Cleave (Zoo Anz 43: 177–1990, 1913) Van Cleave (Ill Natl Hist Surv Bull 13:225–257, 1919) is a North American acanthocephalan originally described from Micropterus salmoides (Lacepede) in Pelican Lake, Minnesota. It is common in Centrarchids but also not infrequent in fishes of other families. A unique population of N. cylindratus was discovered in Peru. It needed to be described and its introduction into Peru investigated. Standard processing of specimens and staining in Borax carmine and fast green for creating whole mounts were employed. Literature sources were available from the OMA personal collection. The descriptive accounts of N. cylindratus have been rather stable over the years since its original description. It has been, however, oddly identified from Gambusia affinis (Baird and Girard) in Peru. Females of the Peruvian specimens were, however, not typical in having a terminal-near terminal gonopore at odds with the sub-ventral position characteristic of the usual populations of N. cylindratus in North America. We describe the Peruvian material and outline the distinct morphological variations from the North American populations in the position of the female gonopore, among other characters. We also explain its introduction into Peru and the translocation of the position of female gonopore to the terminal position. The translocation to the terminal position of the female gonopore in the Peruvian material is attributed to host related developmental factors. The route of introduction of N. cylindratus into Peru through the introduction of G. affinis from the United States has been accounted for. It may be comparable to the introduction of the same acanthocephalan species into northern Mexico via the documented introduction of its primary host, M. salmoides, also from the United States into Mexico in 1930. The introduction of Acanthocephalus dirus Van Cleave (Ill Natl Hist Surv Bull 13:225–257, 1919) (Van Cleave and Townsend, 1936) into Mexico is also discussed.

This study investigates the gastroenteric parasites community of 336 black grouse Lyrurus tetrix, covering a wide part of the totality of the species range in the French Alps and characterized by a long-term sampling (1986–2019). Parasite community was described using common epidemiological descriptors. Additionally, for the most prevalent parasite, a species distribution model (SDM) was built to understand the main factors influencing parasite occurrence. Ascaridia compar, Capillaria caudinflata, cestodes (Raillietina urogalli, R.cesticillus, and Hymenolepis microps), Eimeria sp. (E. lyruri and E.nadsoni), Corrigia corrigia and Acanthocephalus sp. The most prevalent species was C.caudinflata (P: 33%,CI95%: 28–38), whereas the lowest prevalence was recorded for Acantocephalus sp. (P:0.3%,CI95%:-0.3–0.9).The selected SDM for C.caudinflata includes only 3 variables: BIO11 (Mean Temperature of Coldest Quarter), the latitude of sampled animals and the distance from ski tour way. The distribution of C.caudinflata in the French Alps presents sharply defined areas where there are optimal environmental conditions for maintaining the life cycle of this parasite. These are the colder areas, characterized by higher latitude values and close to the ski tour ways. This study provides a valuable contribution to the scarce literature on wild Galliformes, describing the composition of the gastrointestinal parasite community of the black grouse.

Four species of acanthocephalans are reported from gobies of the genus Rhinogobius in western and central Japan: Acanthocephalus gotoi Van Cleave, 1925 from Rhinogobius similis in the Kamo River (Hiroshima Prefecture) and Rhinogobius sp. OR (=orange type) in the Sōja River (Ehime Prefecture) and the Hiwatashi River (Kōchi Prefecture); Acanthocephalus longiacanthus Katahira and Nagasawa, 2014 from Rhinogobius nagoyae and Rhinogobius sp. OR in the Tenchi River (Hiroshima Prefecture), Rhinogobius fluviatilis in the Kamo River, and Rhinogobius sp. OR in the Sōja and Hiwatashi rivers; Acanthocephalus minor Yamaguti, 1935 from Rhinogobius flumineus in the Aruji River (Hiroshima Prefecture); and Southwellina hispida (Van Cleave, 1925) from Rhinogobius flumineus in the Aruji River and the Shika River (Kyōto Prefecture). All these collections represent new host records for the acanthocephalans. New prefecture records are A. gotoi and A. longiacanthus from Hiroshima and Kochi prefectures, and A. minor and S. hispida from Hiroshima Prefecture. Based on the previous and present papers published between the years 1935 and 2018, 48 nominal and some unidentified species of the parasites have been reported from the Japanese Rhinogobius spp. The nominal species include: 3 species in the Myxozoa (Cnidaria); 1 species in the Monogenea; 16 species in the Trematoda; 4 species in the Cestoda (all Platyhelminthes); 3 species in the Nematoda; 5 species in the Acanthocephala; 15 species in the Bivalvia (Mollusca); and 1 species in the Copepoda (Arthropoda).

Three species of acanthocephalans are described from fishes caught in the Pacific coast off eastern Vietnam and from amphibians in the midlands in 2016: (1) Acanthocephalus parallelcementglandatus Amin, Heckmann, Ha, 2014 (Echinorhynchidae), described from 1 male specimen is now fully described from males and females collected from 2 species of amphibians, the similar frog Hylarana attigua Inger, Orlov, Darevsky and the odorous frog Odorrana sp. Fei, Ye, Huang (Ranidae) in Huong Thuy, Hue City and Chu Yang Sin Park, central Vietnam, respectively, as well as from the needlefish Tylosurus sp. Cocco (Belonidae) in Binh Thuân in the Pacific South. The allotype female is designated. Neoechinorhynchus (N.) pennahia Amin, Ha, Ha, 2011 described from 1 female specimen is now fully described from males and females collected from the Toli shad (Chinese herring), Tenualosa toli (Valenciennes) (Clupeidae) in the Pacific north coast off Haiphong. The allotype male is designated. One specimen of Neoechinorhynchus (Neoechinorhynchus) longnucleatus Amin, Ha, Ha, 2011 is also reported from the common ponyfish, Leiognathus equulus (Forssskål) (Leiognathidae) in the Pacific south coast of Nha Trang and its ecology briefly discussed.

Two genera, Callipeltis Steven (Rubiaceae) and Acanthocephalus Kar. & Kir. (Asteraceae), together with five species, Callipeltis cucullaris (L.) DC., Acanthocephalus benthamianus Regel, Galium verticillatum Danthoine ex Lam. (Rubiaceae), Nonea turcomanica Popov (Boraginaceae), and Erysimum croceum Popov (Brassicaceae), are reported as new records to China.

SUMMARYThe acanthocephalan fauna of Australian freshwater fishes was documented from field surveys, a literature survey and examination of specimens registered in Australian museums. From the 4030 fishes, representing 78 of the 354 Australian freshwater fish species (22%), examined for infection seven species of acanthocephalan were recovered. These species comprised five endemic species, three in endemic genera, two species in cosmopolitan genera, one species not fully identified and 1 putative exotic species recovered from eight species of fish. Of theseEdmonsacanthus blairifromMelanotaenia splendida,was the only acanthocephalan found at a relatively high prevalence of 38·6%. These findings are indicative of a highly endemic and possibly depauperate acanthocephalan fauna. Species richness was higher in the tropical regions than the temperate regions of the country. Exotic acanthocephalan species have either not been introduced with their exotic hosts or have been unable to establish their life cycles in Australian conditions. Consequently, acanthocephalans have not yet invaded endemic Australian fish hosts.

Acanthocephalus balkanicus Batchvarov et Combes, 1974 was incompletely described from the northern crested newt, Triturus cristatus (Laurenti) (Amphibia: Salamandridae), a possible synonym of the Balkan crested newt, Triturus ivanbureschi Arntzen et Wielstra, from a pond in village of Pesnopoy, southern Bulgaria. We provide a full description of adult males and females of the same taxon from the olm, Proteus anguinus Laurenti (Amphibia: Proteidae), the only exclusively aquatic cave-dwelling vertebrate in Europe, captured in Postojna-Planina Cave System in Slovenia. Cystacanths were also collected from the cave ecomorph of Asellus aquaticus (Linnaeus) (Crustacea: Asellidae) in the same location. Molecular analysis of specimens from Slovenia revealed that they are genetically almost identical to those of Acanthocephalus anguillae (Müller, 1780), a common parasite of European freshwater fishes. We propose to recognise the morphological and host differences by describing A. balkanicus as a new subspecies of A. anguillae. Acanthocephalus anguillae balkanicus is rather small and cylindrical with cylindrical proboscis having 10 rows of 6 hooks with simple roots each, long neck, large balloon-shaped lemnisci, small spherical anterior testis, and 6 club-shaped cement glands in 3 pairs. SEM images reveal more morphological details and the X-ray scans of gallium cut hooks shows considerably higher levels of phosphorus and calcium in adult hooks than in cystacanth hooks, especially in basal areas. Sulfur levels were higher in the arch and basal area of cystacanth hooks than adult hooks. Considering that both definitive and intermediate hosts of the Slovenian population of this acanthocephalan are bound to cave life, it is possible that its entire life cycle is uniquely completed underground.

Acanthocephalus tumescens (syn. Echinorynchus tumescens Linstow, 1896) Actinopterygii Aplochiton zebra Jenyns (Osmeriformes, Galaxiidae). SI: intestine. SD: adult. L: Chubut Province: Puelo Lake, Epuy��n Lake, Cholila Lake and Rivadavia Lake. R: Fernandez et al. (2012). C: vouchers (MACN-Pa 530/1��� 2). Galaxias maculatus (Jenyns) (Osmeriformes, Galaxiidae). SI: intestine. SD: adult. L: Neuqu��n Province: Pulmar�� Lake (39��08���S��� 71��05���S), ��orquinco Lake (39��09���S��� 71��17���S), Carilafqu��n Lake (39��49���S��� 71��39���S), Currhu�� Chico Lake (39��54���S��� 71��20���S), Meliquina Lake (40��23���S��� 71��17���S), Espejo Chico Lake (40��35���S��� 71��44���S), Espejo Lake (40��41���S��� 71��40���S), Correntoso Lake (40��44���S��� 71��39���S), Nahuel Huapi Lake (41��04���S, 71��25���W��� 41��06���S, 71��40���W); R��o Negro Province: Guti��rrez Lake (41��05���S, 71��25���W), Morenito Lake (41��05���S��� 71��31���S), Mall��n Ingeniero Lake (41��15���S��� 71��40���S), Mascardi Lake (41��17���S, 71��34���W), Moreno Lake (41��18���S, 71��42���W), Los C��sares Lake (41��19���S��� 71��43���S), Roca Lake (41��21���S��� 71��25���S), Guillelmo Lake (41��22���S��� 71��30���S), Hess Lake (41��22���S��� 71��43���S), Los Moscos Lake (41��22���S��� 71��36���S), Steffen Lake (41��31���S��� 71��33���S); Santa Cruz Province: Santa Cruz River (50��00���S��� 69��00���S),Argentino Lake (52��20���S��� 72��20���S). R: Ortubay et al. (1994), Semenas and Trejo (1997), Trejo et al. (2000), Rauque et al. (2002), Revenga et al. (2005), Viozzi et al. (2009), Fernandez (2011), Paterson et al. (2013), Fernandez et al. (2015a,b). C: vouchers (MACN-Pa 386, 461/1���2; UNCo-Pa accession numbers not provided by Semenas and Trejo 1997). Galaxias platei Steindachner (Osmeriformes, Galaxiidae). SI: intestine. SD: adult. L: R��o Negro Province: Los C��sares Lagoon (41��18���S, 71��42���W), Moreno Lake (41��18���S, 71��42���W); Chubut Province: Esperanza Lake (42��13���S, 71��50���W), Cholila Lake (42��27���S, 71��40���W); Santa Cruz Province: Pueyrred��n Lake (47��16���S, 72��00���W); Tierra del Fuego Province: Yehu��n Lake (54��25���S, 67��40���W). R: Ortubay et al. (1994), Rauque et al. (2003, 2006), Paterson et al. (2013). Odontesthes hatcheri (Eigenmann) (Atheriniformes, Atherinopsidae) (type host). SI: intestine. SD: adult. L: R��o Negro Province: Morenito Lake (41��02���S, 68��34���W), Carrilafquen Chica Lake (41��12���S, 69��25���W); Chubut Province: Rivadavia Lake (42��36���S, 71��39���W), Terrapl��n Lagoon (42��59���S, 71��32���W); Tierra del Fuego Province: Ushuaia. C: syntype (ZMH V 4083). R: Linstow (1896), Porta (1905), Ortubay et al. (1994), Flores et al. (2016) (see note below). Olivaichthys viedmensis (MacDonagh) (Siluriformes, Diplomystidae). SI: intestine. SD: adult. L: R��o Negro Province: Nahuel Huapi Lake (41��03���S, 71��25���W), Moreno Lake (41��18���S, 71��42���W), Hess Lake (41��22���S, 71��43���W), Limay River. R: Ortubay et al. (1994), Rauque et al. (2003). Oncorhynchus mykiss (Walbaum) (Salmoniformes, Salmonidae). SI: intestine. SD: adult. L: Rio Negro Province: Alicur�� Reservoir (40��40���S, 71��00���W), Nahuel Huapi Lake (41��03���S, 71��25���W), Moreno Lake (41��18���S, 71��42���W), Hess Lake (41��22���S, 71��43���W), Castilla Creek, Limay River, ��irihuau River; Chubut Province: Cholila Lake (42��27���S, 71��40���W), Futalaufquen Lake (42��50���S, 71��40���W), Terrapl��n Lagoon (42��59���S, 71��32���W), Tres Lake (44��15���S, 71��34���W), Fontana Lake (44��55���S, 71��30���W), Musters Lake (45��30���S, 69��10���W), Grande/Futaleuf�� River, Corcovado/Carrenleuf�� River; Santa Cruz Province: Santa Cruz River. R: Ortubay et al. (1994), Rauque et al. (2002, 2003, 2006, 2018), Tanzola et al. (2009), Fernandez (2011), Paterson et al. (2013) (see note below). Percichthys trucha (Valenciennes) (Perciformes, Percichthyidae). SI: intestine. SD: adult. L: R��o Negro Province: Alicur�� Reservoir (40��40���S, 71��00���W), Nahuel Huapi Lake (41��03���S, 71��25���W), Moreno Lake (41��18���S, 71��42���W), Hess Lake (41��22���S, 71��43���W), Limay River; Chubut Province: Cholila Lake (42��27���S, 71��40���W), Terrapl��n Lagoon (42��59���S, 71��32���W), Musters Lake (45��30���S, 69��10���W); Santa Cruz Province: Santa Cruz River. R: Ortubay et al. (1994), Rauque et al. (2003, 2006), Paterson et al. (2013) (see note below). Salmo salar Linnaeus (Salmoniformes, Salmonidae). SI: intestine. SD: adult. L: Chubut Province: Cholila Lake (42��27���S, 71��40���W). R: Ortubay et al. (1994). Salmo trutta Linnaeus (Salmoniformes, Salmonidae). SI: intestine. SD: adult. L: R��o Negro Province: Nahuel Huapi Lake (41��03���S, 71��25���W), Hess Lake (41��22���S, 71��43���W),Limay River; Chubut Province: Futalaufquen Lake (42��50���S, 71��40���W), Amutui-Quimei Reservoir (43��03���S, 71��45���W). R: Ortubay et al. (1994), Rauque et al. (2018). Salvelinus fontinalis (Mitchill) (Salmoniformes, Salmonidae). SI: intestine. SD: adult. L: R��o Negro Province: Moreno Lake (41��18���S, 71��42���W); Chubut Province: Cholila Lake (42��27���S, 71��40���W), Terrapl��n Lagoon (42��59���S, 71��32���W),General Vintter Lake (43��52���S, 71��30���W),Fontana Lake (44��55���S, 71��30���W), Corcovado/ Carrenleuf�� River; R: Ortubay et al. (1994), Rauque et al. (2003, 2018). Salvelinus namaycush (Walbaum) (Salmoniformes, Salmonidae). SI: intestine. SD: adult. L: Santa Cruz Province: Argentino Lake (50��25���S, 72��50���W). R: Ortubay et al. (1994). Note. Linstow (1896) described Acanthocephalus tumescens from Odontesthes hatcheri [syn. Basilichthys microlepidotus] from Ushuaia, Tierra del Fuego. The type-locality of A. tumescens was obtained from the specimens examined by Linstow (1896) and desposited at the ZMH. Odontesthes hatcheri is distributed to the continental Andean Region of southern South America (Conte-Grand et al. 2015 and references therein). Therefore, it is possible that the type host for Acanthocephalus tumescens could be other similar marine silverside species (see note for Heterosentis heteracanthus above). Ortubay et al. (1994) reported adult specimens of Acanthocephalus tumescens in the intestine of Percichthys colhuapiensis MacDonagh from Musters Lake. Percichthys colhuapiensis is considered a morphotype of Percichthys trucha (see Ruzzante et al. 2011). Rauque et al. (2002) and Fernandez (2011) experimentally infected rainbow trout Oncorhynchus mykiss with specimens of Acanthocephalus tumescens collected from Galaxias maculatus from Mascardi Lake, R��o Negro Province. Fernandez (2011) experimentally infected Oncorhynchus mykiss with Acanthocephalus tumescens by feading rainbow trout with naturally infected Galaxias maculatus from Moreno Lake, Espejo Lake and Guti��rrez Lake, R��o Negro Province. Malacostraca Hyalella patagonica (Cunningham) (Amphipoda, Hyalellidae). SI: hemocoel. SD: cystacanth. L: R��o Negro Province: Moreno Lake (41��05���S, 71��19���W), Guti��rrez Lake (41��12���S, 71��26���W), Mascardi Lake (41��17���S, 71��38���W). R: Rauque and Semenas (2007, 2009, 2011), Rauque and de los R��os Escalante (2013). Hyalella sp. (Amphipoda, Hyalellidae). SI: hemocoel. SD: cystacanth. L: Neuqu��n Province: Espejo Lake (40��41���S, 71��40���W); R��o Negro Province: Mascardi Lake (41��17���S, 71��38���W); Los C��sares Lagoon (41��19���S, 71��43���W), Roca Lake (41��21���S, 71��25���W), Guillelmo Lake (41��22���S, 71��30���W); Chubut Province: Epuy��n Lake (42��11���S, 71��30���W), Rivadavia Lake (42��36���S, 71��39���W), Verde Lake (42��43���S, 71��43���W). R: Rauque (2013)., Published as part of Hern��ndez-Orts, Jes��s S., Kuchta, Roman, Semenas, Liliana, Crespo, Enrique A., Gonz��lez, Ra��l A. & Aznar, Francisco J., 2019, An annotated list of the Acanthocephala from Argentina, pp. 1-64 in Zootaxa 4663 (1) on pages 16-17, DOI: 10.11646/zootaxa.4663.1.1, http://zenodo.org/record/3772372, {"references":["Linstow, O. (1896) Nemathelminthen. Ergebnisse der Hamburger Magalhaensische Sammelreise 1892 / 93, 3, 1 - 22.","Fernandez, V., Semenas, L. & Viozzi, G. (2012) Parasites of the \" Peladilla \" Aplochiton zebra (Osmeriformes: Galaxiidae), from Patagonia (Argentina and Chile). Comparative Parasitology, 79 (2), 231 - 237. https: // doi. org / 10.1654 / 4561.1","Ortubay, S., Semenas, L. G., Ubeda, C. A., Quaggiotto, A. & Viozzi, G. (1994) Catalogo de peces dulceacuicolas de la Patagonia Argentina y sus parasitos metazoos. Direccion de Pesca de la Provincia de Rio Negro, San Carlos de Bariloche, 110 pp.","Semenas, L. & Trejo, A. (1997) Redescription of Acanthocephalus tumescens (von Linstow, 1896) (Palaeacanthocephala: Echinorhynchidae) in Galaxias maculatus (Pisces: Galaxiidae) in Patagonia (Argentina). Systematic Parasitology, 36 (1), 13 - 16. https: // doi. org / 10.1023 / A: 1005725919148","Trejo, A., Semenas, L. & Viozzi, G. (2000) Acanthocephalus tumescens (Acanthocephala, Echinorhynchidae) in Galaxias maculatus (Pisces, Galaxiidae) of Lake Gutierrez, Patagonia, Argentina. Journal of Parasitology, 86 (1), 188 - 191. https: // doi. org / 10.2307 / 3284938","Rauque, C. A., Semenas, L. G. & Viozzi, G. P. (2002) Post-cyclic transmission in Acanthocephalus tumescens (Acanthocephala: Echinorhynchidae). Folia Parasitologica, 49 (2), 127 - 130. https: // doi. org / 10.14411 / fp. 2002.023","Revenga, J. E., Torres, P. F. & Baiz, M. (2005) Impact of a caged-trout farm on parasites of Galaxias maculatus in Lake Moreno, southern Argentina. Journal of Parasitology, 91 (3), 707 - 709. https: // doi. org / 10.1645 / GE- 441 R","Viozzi, G., Semenas, L., Brugni, N. & Flores, V. R. (2009) Metazoan parasites of Galaxias maculatus (Osmeriformes: Galaxiidae) from Argentinean Patagonia. Comparative Parasitology, 76 (2), 229 - 239. https: // doi. org / 10.1654 / 4328.1","Fernandez, M. V. (2011) Influencia de las caracteristicas de los lagos y la piscivoria en la estructuracion de las comunidades de helmintos de galaxidos presa. PhD thesis. Universidad Nacional del Comahue, Bariloche, 181 pp.","Paterson, R. A., Rauque, C. A., Fernandez, M. V., Townsend, C. R., Poulin, R. & Tompkins, D. M. (2013) Native fish avoid parasite spillback from multiple exotic hosts: consequences of host density and parasite competency. Biological Invasions, 15 (10), 2205 - 2218. https: // doi. org / 10.1007 / s 10530 - 013 - 0445 - 8","Fernandez, V., Garibotti, G., Semenas, L. & Viozzi, G. (2015 a) Influence of biotic and abiotic factors on the metazoan parasite communities of a native prey fish: study in 28 Andean Patagonian lakes. Ecologia Austral, 25 (3), 221 - 230.","Rauque, C. A., Viozzi, G. P. & Semenas, L. G. (2003) Component population study of Acanthocephalus tumescens (Acanthocephala) in fishes from Lake Moreno, Argentina. Folia Parasitologica, 50 (1), 72 - 78. https: // doi. org / 10.14411 / fp. 2003.013","Rauque, C. A., Semenas, L. G. & Viozzi, G. P. (2006) Seasonality of recruitment and reproduction of Acanthocephalus tumescens (Acanthocephala) in fishes from Lake Moreno (Patagonia, Argentina). Journal of Parasitology, 92 (6), 1265 - 1269. https: // doi. org / 10.1645 / GE- 764 R 1. 1","Porta, A. (1905) Gli Echinorinchi dei Pesci. Archivio Zoologico Italiano, 2, 149 - 214.","Flores, V., Semenas, L., Rauque, C., Vega, R., Fernandez, V. & Lattuca, M. (2016) Macroparasites of silversides (Atherinopsidae: Odontesthes) in Argentina. Revista Mexicana de Biodiversidad, 87 (3), 919 - 927.","Rauque, C., Viozzi, G., Flores, V., Vega, R., Waicheim, A. & Salgado-Maldonado, G. (2018) Helminth parasites of alien freshwater fishes in Patagonia (Argentina). International Journal for Parasitology: Parasites and Wildlife, 7 (3), 369 - 379. https: // doi. org / 10.1016 / j. ijppaw. 2018.09.008","Tanzola, R. D., Semenas, L. & Viozzi, G. (2009) Manejo y estado actual del conocimiento de los parasitos de peces cultivados en Argentina. In: Tavares-Dias, M. (Ed.), Manejo e Sanidade de Peixes em Cultivo. Embrapa Amapa, Macapa, pp. 438 - 468.","Conte-Grand, C., Sommer, J., Orti, G. & Cussac, V. (2015) Populations of Odontesthes (Teleostei: Atheriniformes) in the Andean region of Southern South America: body shape and hybrid individuals. Neotropical Ichthyology, 131 (1), 137 - 150. https: // doi. org / 10.1590 / 1982 - 0224 - 20130094","Ruzzante, D. E., Walde, S. J., Macchi, P. J., Alonso, M. & Barriga, J. P. (2011) Phylogeography and phenotypic diversification in the Patagonian fish Percichthys trucha: the roles of Quaternary glacial cycles and natural selection. Biological Journal of the Linnean Society, 103 (2), 514 - 529. https: // doi. org / 10.1111 / j. 1095 - 8312.2011.01682. x","Rauque, C. A. & Semenas, L. (2007) Infection pattern of two sympatric acanthocephalan species in the amphipod Hyalella patagonica (Amphipoda: Hyalellidae) from Lake Mascardi (Patagonia, Argentina). Parasitology Research, 100 (6), 1271 - 1276. https: // doi. org / 10.1007 / s 00436 - 006 - 0420 - 8","Rauque, C. A. & Semenas, L. (2009) Effects of two acanthocephalan species on the reproduction of Hyalella patagonica (Amphipoda, Hyalellidae) in an Andean Patagonian Lake (Argentina). Journal of Invertebrate Pathology, 100 (1), 35 - 39. https: // doi. org / 10.1016 / j. jip. 2008.10.001","Rauque, C. A. & Semenas, L. (2011) Parasite volume as an indicator of competition: the case of Acanthocephalus tumescens and Pseudocorynosoma sp. (Acanthocephala) in their intermediate host. Journal of Parasitology, 97 (6), 999 - 1002. https: // doi. org / 10.1645 / GE- 2823.1"]}

Purpose The study aims to characterise and compare the helminth assemblages and helminth infracommunities in the marsh frog, Pelophylax ridibundus and the edible frog, P. esculentus collected in the northern part of Ukraine. Methods Occurrence and abundance of the helminths were analysed by calculating the prevalence, intensity, and mean abundance of infection; similarities between the infracommunities were estimated by the Bray–Curtis index and visualised using nMDS plots. Dissimilarities were estimated using the ANOSIM and SIMPER routines. Results In total, 27 helminth species were found in 143 frogs. Pelophylax ridibundus (n = 86) harboured 20 species of helminths, 24 species were found in P. esculentus (n = 57), and 17 species were shared by the two hosts. Oswaldocruzia bialata and larval Strigea sp. were absent in P. ridibundus, while they reached the prevalence of 30% and 10%, respectively, in P. esculentus. Cosmocerca ornata, Diplodiscus subclavatus, Opisthioglyphe ranae, and Codonocephalus urniger had significantly larger prevalence in P. ridibundus, whereas Haematoloechus asper was found to be more prevalent in P. esculentus. Acanthocephalus ranae, Icosiella neglecta, Haematoloechus variegatus, Pleurogenes claviger, Pleurogenoides medians, and Prosotocus confusus were equally common in both hosts. Helminth infracommunities in the two hosts had identical species richness (1–10 species, 4 on average); abundance was significantly higher in P. ridibundus. Conclusions Helminth assemblages of the two hosts in northern Ukraine are rather similar; however, small but significant differences were found in their species composition, parameters of infection in some species, and structure of helminth infracommunities

Acanthocephalans of the order Echinorhynchida are one of the most diverse groups in their phylum, with approximately 470 species classified into 11 families that largely consist of parasites of freshwater, brackish and marine fishes and, sporadically, reptiles and amphibians distributed worldwide. Previous phylogenies inferred with molecular data have supported the paraphyly or polyphyly of some families, suggesting that most of them have been diagnosed based on unique combinations of characters, rather than shared derivative features. We expand the taxonomic sampling of several genera such as Acanthocephalus, Echinorhynchus and Pseudoacanthocephalus of Echinorhynchidae from diverse biogeographical zones in the Americas, Europe and Asia with the aim of testing the monophyly of the family by using two molecular markers. Sequences from small (SSU) and large (LSU) subunits of ribosomal DNA were obtained for six species representing the genera Acanthocephalus and Echinorhynchus from the Neotropical, Nearctic, Palearctic and Oriental regions. These sequences were aligned with other sequences available in the GenBank dataset from Echinorhynchidae. Phylogenetic trees inferred with the combined (SSU + LSU) and the individual data sets consistently placed the genera Acanthocephalus, Pseudoacanthocephalus and Echinorhynchus into three independent lineages. Two families, Paracanthocephalidae Golvan, 1960, and Pseudoacanthocephalidae Petrochenko, 1956, were resurrected to accommodate the genera Acanthocephalus and Pseudoacanthocephalus, respectively. The species of the genus Acanthocephalus from the Nearctic, Palearctic and Oriental biogeographic regions formed a clade that was well supported. However, Acanthocephalus amini from the Neotropical region was nested inside Arhythmacanthidae. Therefore, the genus Calakmulrhynchus was created to accommodate A. amini and resolve the paraphyly of Acanthocephalus. Finally, the diagnoses of the families Echinorhynchidae and Arhythmacanthidae were amended. The molecular phylogenies should be used as a taxonomic framework to find shared derived characters (synapomorphies) and build a more robust classification scheme that reflects the evolutionary history of the acanthocephalans.

Objective To describe the pathological manifestation of the Acanthocephalus dirus ( A. dirus ) infestation in Thunnus albacares ( T. albacares ) from southeast coast of India. Methods The parasite-infested fishes were collected from Nagapattinam landing centre of Tamil Nadu from southeast coast of India. The Acanthocephala morphology, gross pathology, histopathology and histochemistry were investigated. Results T. albacares were severely infested with A. dirus , the group of Acanthocephala attached to the posterior region of the intestine. The adult worm proboscis was cylindrical and the length and width ranging between 2.7–6.4 mm and 0.8–1.3 mm, respectively. Histopathologically, the infested intestinal mucosal epithelium, stratum granulosum, lamina propria, muscular and serosa layers were highly degraded. The lesions were infiltrating with basophil-like inflammatory cells. The parasite-affected lesions were histochemically positive for alcian blue, azo dye, toluidine blue and oil red O. Conclusions This is the new host for the parasite A. dirus in T. albacares . On the basis of histological and histochemical findings, the lesions were highly damaged due to the parasitic infestation. The high density of the parasite and severe penetration of the proboscis into the intestinal tissues are the main reason for the pathogenicity in the host.

The acanthocephalan Acanthocephalus dirus is a trophically transmitted parasite that infects freshwater isopods as intermediate hosts and fish as definitive hosts. Using a laboratory-based experiment, we examined if parasite infection was associated with changes in mating behaviour, refuge use and neurochemical levels of infected isopods (Caecidotea intermedius). Infected isopods were less likely to engage in mating behaviour and more likely to be located in the open than uninfected isopods. Infected isopods also contained lower levels of serotonin (5-HT) and dopamine (DA) and had a greater mass of neural tissue (CNS) than uninfected isopods. We propose that the parasite-related changes in mating behaviour and refuge use may be modulated by the serotonergic and dopaminergic systems. We also suggest that the parasites could potentially be modulating these behavioural changes by exploiting the neural-immune system of the hosts through their neuroinflammatory responses.

This study was conducted at Lake Hashenge, Tigray, Ethiopia from the period of November to April 2009 to identify parasites of fish. The objective of this study was to identify parasite of fish at Lake Hashenge to determine the prevalence of parasitic disease of fish, to have baseline information fish parasite in The lake Hashenge. A total of 442 different species of were sampled. These include 217 of Mirror carp and 225 of Oreochromis niloticus. The fish were thoroughly examined both externally and internally for the presence of parasites. The major parasites identified were CLinostomum species from 96(44.2%) of Mirror carp and 64(28.4%) of Orechromis niloticus. Clinostomum species were recovered from the feaces of the fish (gastrointestinal tract). The nematode genera of capillaria identified from the GIT of 13(6%) Mirror carp and 14(6.2%) Oreochromis niloticus. The genera of Acanthocephalus were recovered from the GIT of 29(13.4%) of mirror carp and…

Specimens of the echinorhynchid acanthocephalan Acanthocephalus minor Yamaguti, 1935 were collected from the rectum of a dark sleeper, Odontobutis obscura (Temminck and Schlegel, 1845), in an irrigation canal near Lake Biwa, Shiga Prefecture, west-central Japan. This represents a rediscovery of A. minor in the Lake Biwa basin after a gap of nearly 80 years. It appears not to be distributed in Lake Biwa proper, but to occur rarely in rivers and irrigation canals of a limited coastal area around the lake. To date, 10 nominal species of acanthocephalan in four families and three orders have been reported from fish in the Lake Biwa basin. Among these, striking morphological similarities between Acanthocephalus aculeatus Van Cleave, 1931 and its congener A. opsariichthydis Yamaguti, 1935 are noted. It is furthermore suggested that A. gotoi Van Cleave, 1925 could not maintain its population after the basin's wild population of its major host, Anguilla japonica Temminck and Schlegel, 1846, disappeared in the mid-1960s.

Between November 2012 and July 2013, 34 banded sculpins (Cottus carolinae) were collected from 5 counties of northern Arkansas and examined for helminths. Five (19%) were infected with 1 or more helminths, including 2 (6%) with the trematode Crepidostomum cooperi, 3 (9%) with the trematode Plagioporus sp., 1 (3%) with the nematode Spiroxys sp., and 1 (3%) with the acanthocephalan Acanthocephalus tahlequahensis. One (3%) was concurrently infected with C. cooperi, Plagioporus sp., and Spiroxys sp. We document new host records for each of these helminths and 2 new distributional records for C. cooperi and A. tahlequahensis.

Five helminths, including a new echinorhynchid acanthocephalan Acanthocephalus longiacanthus n. sp., are described based on specimens from the giant mottled eel Anguilla marmorata Quoy & Gaimard caught in a small river, western Japan. The new acanthocephalan is distinguished from the other congeners in terms of hook arrangement (8–9 longitudinal rows with 5–6 hooks per row) on proboscis, maximum length of hook blade (81–95 μm in male, 150–190 μm in female), lemnisci being longer than proboscis receptacle, and small-sized eggs (80–83 μm). Two monogeneans, Pseudodactylogyrus anguillae (Yin & Sproston, 1948) and P. bini (Kikuchi, 1929), and two acanthocephalans, Acanthocephalus gotoi Van Cleave, 1925 and Southwellina hispida (Van Cleave, 1925), were also found; this new material is described. The monogeneans are notorious as invasive parasites spreading worldwide via anthropogenic transportations of anguillid eels, but in Japanese waters A. marmorata appears to be an indigenous host for these parasites. Anguilla marmorata is a new host record for the acanthocephalans A. gotoi and S. hispida.

The Eurasian otter Lutra lutra (Linnaeus, 1758) is a typical representative of carnivorous mammals from the family of mustelids (Mustelidae) which are closely connected with aquatic ecosystems. Parasitofauna of the otter is poorly identified, e.g. only two specimens have been examined in Poland for the presence of parasites. Currently, three species of parasites were found in one otter: the nematode Oswaldocruzia filiformis (Goeze, 1782), the acanthocephalan Acanthocephalus ranae (Schrank, 1788) and the skin mite from the Demodecidae family. Demodex sp. is a new species to science, while O. filiformis and Demodex sp. are new parasites for the otter throughout the species range. Furthermore, A. ranae was found for the first time in the otter from the area of Poland. The recorded helminths are typical parasites of amphibians and reptiles, and their occurrence in the Eurasian otter may result from postcyclic transmission from primary hosts.

Disease mediated impacts of exotic species on their native counterparts are often ignored when parasite-free individuals are translocated. However, native parasites are frequently acquired by exotic species, thus providing a novel mechanism through which native host-parasite dynamics may be altered. In Argentina, multiple exotic salmonids are host to the native fish acanthocephalan parasite Acanthocephalus tumescens. Field evidence suggests that rainbow trout, Oncorhynchus mykiss, may be a major contributor to the native parasites population. We used a combination of experimental infections (cystacanth and post-cyclic) and dynamics population modelling to determine the extent to which additional exotic salmonid hosts may alter A. tumescens infections in native freshwater fish. Experimental cystacanth infections demonstrated that although A. tumescens established equally well in native and exotic hosts, growth and maturity was superior in exotic O. mykiss. Experimental post-cyclic infections also showed greater establishment success of A. tumescens in O. mykiss, though post-cyclic transmission did not result in greater parasite fitness in additional hosts (measured as length or maturity). Dynamic population modelling, however, suggested that exotic salmonids may have a very limited influence on the A. tumescens population overall, due to the majority of A. tumescens individuals being maintained by more abundant native hosts. This research highlights the importance of considering both a hosts relative density and its competency for parasites when evaluating whether exotic species can modify native host-parasite dynamics. Fil: Paterson, Rachel A.. University Of Otago. Dept.of Zoology; Canadá. The Queens University Of Belfast; Irlanda Fil: Rauque Perez, Carlos Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación en Biodiversidad y Medioambiente; Argentina Fil: Fernández, María Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Patagonia Norte. Instituto de Investigación En Biodiversidad y Medioambiente; Argentina Fil: Townsend, Colin R.. University Of Otago; Nueva Zelanda Fil: Poulin, Robert. University Of Otago. Department Of Zoology; Nueva Zelanda Fil: Tompkins, Daniel M.. Crown Research Institutes. Landcare Research; Nueva Zelanda

The acanthocephalan Acanthocephalus dirus is a trophically transmitted parasite that modifies both the physiology and behavior of its intermediate host (isopod) prior to transmission to its definitive host (fish). Infected isopods often contain multiple A. dirus individuals and we examined the relationships between host sharing, body size, energy content, and host modification to determine if host sharing was costly and if these costs could influence the modification of host behavior (mating behavior). Using field-based measures of parasite energy content (glycogen, lipid) and parasite body size (volume), we showed that host sharing was costly in terms of energy content but not in terms of body size. Analysis of the predictors of host behavior revealed that energy content, and body size, were not predictors of host behavior. Of the variables examined, parasite intensity was the only predictor of host behavior. Hosts that contained more parasites were less likely to be modified (i.e., less likely to undergo mating suppression). We suggest that intraspecific competition influenced parasite energy content and that the costs associated with competition are likely to shape the strategy of growth and energy allocation adopted by the parasites. These costs did not appear to have a direct effect on the modification of host mating behavior.

In total, 288 slimy sculpins, Cottus cognatus, were collected in September 2003 from 6 Lake Michigan, U.S.A., ports, along with 220 ninespine sticklebacks, Pungitius pungitius, from 3 ports. The ports included Waukegan, Illinois; Port Washington (PW) and Sturgeon Bay (SB), Wisconsin; and Manistique (MS), Frankfort (FF), Ludington (LD), and Saugatuck, Michigan. Echinorhynchus salmonis infected sculpins from 6 ports, Acanthocephalus dirus infected sculpins from 4 ports, and Neoechinorhynchus pungitius infected sculpins from 3 ports. Echinorhynchus salmonis infected significantly more sculpins at PW and at FF than at MS and LD. There were several significant differences in the intensities and abundances of E. salmonis among ports. Acanthocephalus dirus significantly infected more sculpins and had significantly higher abundances at FF than at PW, MS, and LD. Echinorhynchus salmonis, A. dirus, and N. pungitius infected sticklebacks from SB, MS, and FF. Neoechinorhynchus pungitius significantly infected more sculpins and more sticklebacks, and it had significantly higher abundances at MS than at FF. Neoechinorhynchus pungitius was the most common acanthocephalan in C. cognatus and P. pungitius at MS. These acanthocephalan species infecting C. cognatus and P. pungitius corresponded in their occurrence to those organisms that serve as their intermediate hosts found in the stomachs of both fish species. Potential changes in the diet of C. cognatus played a role in significant differences found for E. salmonis and N. pungitius at MS. One of these acanthocephalan species was always the most numerous helminth species found in the digestive tracts of P. pungitius and C. cognatus from these Lake Michigan ports.

In acanthocephalans, dispersal typically occurs when eggs that have been released in the intestines of definitive hosts are expelled with the feces. We examined whether the acanthocephalan Acanthocephalus dirus adopts a strategy of dispersal in which eggs are carried into the environment by gravid females. Using a combination of field surveys and lab-based experiments, we showed that the A. dirus female retained eggs as they passed out of the intestines and that these eggs could develop in intermediate hosts (sediment-dwelling isopods). Lab-based behavioral experiments revealed that the bodies of gravid females were attractive to foraging isopods. We propose that a strategy of egg dispersal could occur in A. dirus in which eggs are carried into the environment by females. This strategy could increase transmission success by dispersing eggs closer to the sediment, rather than in the water column, and by directing the feeding behavior of target hosts.

This study was undertaken to identify the community composition, structure, and dynamics of helminths infecting the gastrointestinal tract (GIT) of lake whitefish (Coregonus clupeaformis) collected from 4 sites in northern lakes Huron (Cheboygan and De Tour Village) and Michigan (Big Bay de Noc and Naubinway) from fall 2003 through summer 2006. A total of 21,203 helminths was retrieved from the GITs of 1,284 lake whitefish. Approximately 42% (SE = 1.4%) of the examined lake whitefish were infected with at least 1 helminth species in their GIT, with a mean intensity of 39.4 worms/fish (SE = 0.3) and a mean abundance of 16.4 worms/fish (SE = 0.1). Collected helminths appeared to be generalists and consisted of 2 phyla (Acanthocephala and Cestoda) and 5 species (Acanthocephalus dirus, Neoechinorhynchus tumidus, Echinorhynchus salmonis, Cyathocephalus truncatus, and Bothriocephalus sp.). Lake whitefish from Lake Huron on average had greater infection prevalences, abundances, and intensities than did fish from Lake Michigan. Infection parameters for each of the helminth species generally followed the same pattern observed for the combined data. Acanthocephalus dirus was the most prevalent and abundant helminth in lake whitefish GITs, although intensity of infection was the greatest for C. truncatus. Helminth infection parameters often peaked in the spring while diversity was greatest in the winter samples. There was substantial temporal variability in helminth infections with prevalences, abundances, and intensities often fluctuating widely on consecutive sampling occasions. Analysis of the GIT helminth community composition suggested that 3 (Big Bay de Noc, De Tour Village, and Cheboygan) of the 4 primary spawning sites, overall, had similar community compositions. The reason for the observed spatial and temporal variability in the lake whitefish GIT helminth infections remains to be elucidated. The findings of this study represent the most comprehensive parasitological study ever conducted on lake whitefish in the Great Lakes and will provide valuable information for future comparisons.

In this research, two bufonid toad species (Bufo bufo and Bufo (Pseudepidalea) viridis) were collected in Denizli province (Inner-west Anatolia Region — the eastern part of Aegean Region) Turkey between 2006 and 2009 and examined first time for helminths. Of 6 Bufo bufo, 5 (97.87 %) were infected with one or more helminths, of 47 Bufo viridis 46 (87.91 %) were infected with one or more helminths. The helminth fauna of Bufo bufo included 5 species of which were 4 species of nematodes (Rhabdias bufonis, Oswadocruzia filiformis, Cosmocerca ornata, and Oxysomatium brevicaudatum), and 1 species of acanthocephalan (Acanthocephalus ranae). The helminth fauna of Bufo (Pseudepidalea) viridis comprised 7 species with 1 species of monogenean (Polystoma viridis), 1 species of cestoda (Nematotaenia dispar), and 5 species of nematodes (R. bufonis, O. filiformis, C. ornata, C. commutata, and O. brevicaudatum). R. bufonis, O. filiformis, C. ornata, and O. brevicaudatum were observed in both bufonid toads.

Parasitic fauna of water frogs was mainly studied in the second half of the 20th century. However, these studies were done without differentiation into species and hybrids and pooled the 3 taxa as “water frogs” or “green frogs”. The aim of this study was to make an inventory of helminth species as well as their prevalence and intensity of infection in the two parental species (Pelophylax ridibundus and P. lessonae) and the hybrid (P. esculentus) of water frogs from 3 big populations composed of hundreds or thousands of individuals inhabited natural and seminatural landscapes in Poland. Eight helminth species were found: Polystoma integerrimum, Diplodiscus subclavatus, Opisthoglyphe ranae, Gorgodera cygnoides, Haematoloechus variegatus, Oswaldocruzia filiformis, Cosmocerca ornata and Acanthocephalus ranae. The results were compared with data from other, polish and European studies. Additionally we compared the level of infection among water frog taxa.

This study gathered the largest amount of evidence available concerning the presence of helminths in the Hoplias malabaricus species (Trahira, traira in Portuguese) from limnic ecosystems in South America. At least 18 species of helminths belonging to 15 genera, 14 families, 10 orders, and 8 classes were found. The greatest diversity of parasitic species was observed among the Digeneans and acanthocephalus. Throughout the text, helminths are presented in four sections corresponding to their phyla: Platyhelminthes, Acanthocephala, Nematoda, and Annelida. The different niches occupied by the Trahira in the heteroxenic helminth cycles are also analyzed, verifying whether this fish acts as an intermediate or a definitive host.

In this report, European common toads; Bufo bufo, European green toads Bufo viridis and marsh frogs Rana ridibunda were collected in Amasya, Çorum, and Tokat Provinces (Middle Black Sea Region of Turkey) 2005 and 2006 and examined for helminths. Two of 2 (100 %) Bufo bufo and 8 of 8 (100 %) Bufo viridis and 57 of 63 (90.5 %) Rana ridibunda were infected with 1 or more helminths. The helminths of B. bufo included Oswaldocruzia filiformis and Oxysomatium brevicaudatum. The helminth fauna of B. viridis comprised 5 species: 1 species of trematode (Pleurogenoides medians), 1 species of cestode (Nematotaenia dispar) and 3 species of nematodes, (Oswaldocruzia filiformis, Cosmocerca ornata, and Oxysomatium brevicaudatum), while the helminth fauna of Rana ridibunda comprised 9 species: 4 species of trematodes (Gorgodera cygnoides, Gorgoderina vitelliloba, Haematoloechus breviansa, and Opisthioglyphe ranae), 3 species of nematodes Oswaldocruzia filiformis, Cosmocerca ornata, and Oxysomatium brevicaudatum), and 2 species of acanthocephalans (Pomphorhynchus laevis and Acanthocephalus ranae). Oswaldocruzia filiformis, Cosmocerca ornata, and Oxysomatium brevicaudatum were collected from all three host species. In addition, Pleurogenoides medians represents a new host record for Bufo viridis in Turkey.

Helminth parasite fauna in anuran amphibia were investigated during the general faunistic surveys of Kalesar Wildlife Sanctuary, situated in Haryana state. Three species of amphibian hosts were found to harbour 12 genera of helminth parasites. The prevalence, intensity and abundance were studied. Euphlyctis cyanophlyctis harboured maximum parasite species followed by Fejervarya limnocharis and Duttaphrynus melanostictus. In E. cyanophlyctis, among nematode parasites, the genus Camallanus was most prevalent followed by Cosmocerca and Cosmocercoides, whereas, Rhabdias and Aplectana were the least prevalent genera. Among trematode parasites, Ganeo was the most prevalent genus and least was Diplodiscus. Acanthocephalus was recovered only once and no cestode infection was found. In F. limnocharis, the most prevalent nematode genus was Oxysomatium, followed by Cosmocerca and the only trematode recorded was Ganeo, whereas, cestode Proteocephalus was also recovered once. In D. melanostictus, only two nematode genera were recovered of which Oxysomatium was dominant followed by Cosmocerca. The helminth parasite community in anuran amphibia of Kalesar WLS comprised 52.9% of nematodes, 46.2% of trematodes, 0.58% cestodes and 0.29% acanthocephala.

The digestive tracts of 29 Hemidactylus bowringii from Hong Kong, China were examined for helminths. One species of Cestoda, Oochoristica javaensis, two species of Nematoda, Parapharyngodon maplestoni and Spauligodon hemidactylus, and one species of Acanthocephala, Acanthocephalus bufonis, were found. These helminths are opportunistic generalists that infect other lizard species and each species represents a new helminth record for H. bowringii. Hong Kong, China is a new locality record for O. javaensis, P. maplestoni, and S. hemidactylus.

Acanthocephalus lutzi (Hamann, 1891) is proposed to be transferred to the genus Pseudoacanthocephalus Petrochenko, 1956 based on the type material from Rhinella marina (L.) from Brazil and recently collected material from R. arenarum (Hensel) from Argentina. Pseudoacanthocephalus is characterised by the following features: a cylindrical trunk without spines, a cylindrical proboscis, testes in tandem, a compact cluster of cement glands, a nearly terminal male genital pore, a ventral and sub-terminal female genital pore, and egg without polar prolongations, containing a holoechinate acanthor. Pseudoacanthocephalus lutzi comb. n. has a proboscis armature of 14-18 longitudinal rows of 5-8 hooks each, with all roots formed by a posteriorly directed longitudinal spatulate sheet having a central rib, and an inconspicuous sheet directed anteriorly; a variable number (4, 5 or 6) of cement glands; a cerebral ganglion located near the base of the proboscis receptacle; digitiform to claviform lemnisci, as long as, or slightly shorter or slightly longer than the proboscis receptacle; a sigmoid-shaped posterior end in males; an egg with a conspicuous fibrillar coat; and one of the larval hooks more robust and different in shape than the others. Additionally, the type material of Acanthocephalus saopaulensis Smales, 2007 from Rhinella icterica (Spix) from Brazil and a paratype of A. caspanensis Fernández et Ibarra Vidal, 1992 from R. spinulosa (Wiegmann) from Chile were studied. Acanthocephalus saopaulensis is considered conspecific with P. lutzi and A. caspanensis is transferred to Pseudoacanthocephalus because it possesses all the characters of the genus mentioned above. The use of characters such as egg morphology and host ecology for distinguishing Acanthocephalus from Pseudoacanthocephalus is also discussed.

A total of 33 agile frogs (Rana dalmatina) were collected from 7 localities in Edirne, Bursa and Adapazarı Provinces (Northwest of Turkey), between 1987–2007 and examined for the first time for helminths. R. dalmatina harbored one species of Monogenea (Polystoma sp.), 3 species of Digenea (Diplodiscus subclavatus, Pleurogenoides medians, and Pleurogenes claviger), 4 species of Nematoda (Rhabdias bufonis, Oswaldocruzia filiformis, Cosmocerca ornata, and Oxysomatium brevicaudatum) and one species of Acanthocephala (Acanthocephalus ranae). All helminths represent new host records for Rana dalmatina in Turkey.

Two hundred eighty-eight ranid frogs from Papua New Guinea collected from 2002 to 2005 were examined for endoparasites: Platymantis adiastolus, P. boulengeri, P. browni, P. gilliardi, P. papuensis, P. schmidti, Rana daemeli, R. garritor, R. jimiensis, R. milneana, and R. papua. Found were one species of Cestoda (as cysticerci), three species of Digenea (Opisthioglyphe cophixali, Diplodiscus amphichrus, and Mesocoelium monas), 18 species of Nematoda (adults of Abbreviata oligopapillata, Aplectana krausi, Aplectana macintoshii, Aplectana zweifeli, Cosmocerca novaeguineae, C. tyleri, Desmognathinema papuensis, Falcaustra papuensis, Icosiella papuensis, Meteterakis crombiei, Ochoterenella papuensis, Paracapillaria spratti, Pseudorictularia dipsarilis, Rhabdias australiensis, Seuratascaris numidica, larvae of Abbreviata sp., and Ascaridae gen. sp.), two species of Acanthocephala (Acanthocephalus bufonis and cystacanths of a second species), and one species of Pentastomida (nymphs of Kiricephalus sp.). Sixty-seven new host records, one new country record, and several new island records are reported. Nematodes composed 18/24 (75%) of the species present. Thirteen of the 24 endoparasite species found currently appear to be endemic to Papua New Guinea.

The helminth fauna of lungs, small intestine, and rectum of 83 female specimens of Pelophylax kl. esculentus was investigated. Three helminth groups, Trematoda, Nematoda, and Acanthocephala were recorded. The sample was dominated by the class Trematoda. This class was represented by 8 adult and 2 larval species. Opisthioglyphe ranae and Pleurogenoides medians were the dominant fluke species. The data show the occurrence of Acanthocephalus ranae in frogs inhabiting Vojvodina Province. The most frequent Nematoda was Oswaldocruzia filiformis. The greatest number of parasitic species and individuals was isolated from the small intestine. Infestation of individual parasitic groups was greater than that of mixed groups. The most frequent combination was T/N while analysed organs were most frequently invaded by a parasitic species only. Antagonism between genus Rhabdias and Haematoloechus and between species Aplectana acuminata and Opisthioglyphe ranae was ascertained.