Tapeworms of the genus Spirometra Faust, Campbell et Kellogg, 1929 have long been known as intestinal parasites of carnivores and their larvae (spargana) have been found in various vertebrates. Nevertheless, their species diversity, host associations and geographical distribution remain poorly understood. Molecular data clearly confirm the validity of the genus, which has been synonymised by several authors with Diphyllobothrium Cobbold, 1858. Despite morphological similarities between the species of the two genera, they are not closely related and also differ in their life cycle. The present review provides a list of the species recognised as valid and additional genotypes that may represent other species, with a basic characterisation of each taxon and comments on their validity, the probable range of definitive and intermediate hosts, and their distribution. The existing taxonomic problems and the insufficient knowledge of the host specificity and distribution of Spirometra tapeworms can only be solved by combining molecular and morphological data, i.e. by comparing genetically characterised specimens with corresponding morphological vouchers (hologenophores). Further targeted sampling and surveys are required to clarify the distribution and host associations.

• Keywords
• Broad tapeworms, Diversity, Geographical distribution, Host range, Molecular phylogeny, Sparganosis, Zoonosis,
• Publication type
• Journal Article MeSH
• Review MeSH

The global threat of neglected tropical diseases (NTDs) constitutes a public health issue in underdeveloped countries. Zoonotic helminthiases are the most common human NTD agents in developing countries in sub-Saharan Africa, Asia, and the Americas, causing a global burden of disease that exceeds that of more recognized infectious diseases such as malaria and tuberculosis. Wild canids are well-known mammals that act as natural reservoirs of zoonotic-relevant helminthiasis worldwide, thus playing a pivotal role in their epidemiology and transmission to humans. Here we evaluate the occurrence of zoonotic gastrointestinal helminths in two Neotropical wild canid species from the Amazonian and Andean regions of Colombia, i.e., the bush dog (Speothos venaticus) and the crab-eating fox (Cerdocyon thous). We recovered tapeworm proglottids from bush dog fecal samples and identified them molecularly as the canine-specific lineage of Dipylidium caninum by using cytochrome c oxidase subunit I (cox1) gene sequences. Moreover, examination of a crab-eating fox during necropsy revealed the presence of non-embryonated eggs of the neglected nematode Lagochilascaris cf. minor, in addition to eggs and gravid proglottids of the cestode Spirometra mansoni. These findings represent the first report of zoonotic-relevant cestodes, i.e., D. caninum ("canine genotype"), S. mansoni, and the nematode L. cf. minor, in bush dogs and crab-eating foxes as final hosts. The occurrence of these zoonotic helminthiases in wild canid species calls for regular monitoring programs to better understand the epidemiology and transmission routes of neglected dipylidiasis, lagochilascariosis, and sparganosis in South America.

• Keywords
• Neotropics, dipylidiasis, lagochilascariosis, neglected, sparganosis, wild canids, zoonosis,
• Publication type
• Journal Article MeSH

The tapeworms of fishes (Chondrichthyes and Actinopterygii) account one-third (1670 from around 5000) of the total tapeworm (Platyhelminthes: Cestoda) species diversity. In total 1186 species from 9 orders occur as adults in elasmobranchs (sharks, rays and chimaeras), and 484 species from 8 orders mature in ray-finned fishes (referred to here as teleosts). Teleost tapeworms are dominated by freshwater species (78%), but only 3% of elasmobranch tapeworms are known from freshwater rays of South America and Asia (Borneo). In the last 2 decades, vast progress has been made in understanding species diversity, host associations and interrelationships among fish tapeworms. In total, 172 new species have been described since 2017 (149 from elasmobranchs and 23 from teleosts; invalidly described taxa are not included, especially those from the Oriental region). Molecular data, however, largely limited to a few molecular markers (mainly 28S rDNA, but also 18S and cox1), are available for about 40% of fish tapeworm species. They allowed us to significantly improve our understanding of their interrelationships, including proposals of a new, more natural classification at the higher-taxonomy level (orders and families) as well as at the lower-taxonomy level (genera). In this review, we summarize the main advances and provide perspectives for future research.

• Keywords
• DNA sequencing, Distribution, elasmobranchs, host associations, pathogens, phylogenetic relationships, ray-finned fish, species diversity, taxonomy,
• MeSH
• Cestoda * genetics   MeSH
• Cestode Infections * epidemiology   veterinary   MeSH
• Diphyllobothrium * MeSH
• Elasmobranchii * MeSH
• Phylogeny MeSH
• Fish Diseases * epidemiology   MeSH
• Fishes MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Review MeSH

The geographic distribution of Spirometra erinaceieuropaei (Cestoda: Diphyllobothriidea), the causative agent of food/water-borne sparganosis, is restricted to Europe, where infected canids, felids, mustelids, suids, and reptiles have been documented from Poland, Ukraine, Belarus, Russia, Serbia, Estonia, Latvia, and Finland. The main objective of the current study was to map the molecular divergence of S. erinaceieuropaei from Finland using the complete sequences of the mitochondrial cytochrome c oxidase subunit 1 gene (cox1 mtDNA). Seven cox1 haplotypes were determined in 15 tapeworms from Eurasian lynx (Lynx lynx) from three localities in southern Finland. In addition, the first inter-population study of S. erinaceieuropaei based on currently obtained data on cox1 from Finland and previously published data from Finland, Latvia, Ukraine, and Poland, was performed. The haplotype network showed a star-like pattern without specific subdivision of lineages according to the locality. Samples from Finland, Latvia, and Poland shared several haplotypes and formed the common Baltic lineage. The haplotype of S. erinaceieuropaei from Ukraine was unique and placed on a separate mutational pathway, suggesting a different lineage of the parasite.

TITLE: Interrelations génétiques de Spirometra erinaceieuropaei (Cestoda, Diphyllobothriidea), l’agent causal de la sparganose en Europe. ABSTRACT: La distribution géographique de Spirometra erinaceieuropaei (Cestoda : Diphyllobothriidea), l’agent causal de la sparganose d’origine alimentaire/hydrique, est limitée à l’Europe, où des canidés, félidés, mustélidés, suidés et reptiles infectés ont été documentés en Pologne, Ukraine, Biélorussie, Russie, Serbie, Estonie, Lettonie et Finlande. L’objectif principal de la présente étude était de cartographier la divergence moléculaire de S. erinaceieuropaei de Finlande à l’aide des séquences complètes du gène mitochondrial de la sous-unité 1 de la cytochrome c oxydase (ADNmt cox1). Sept haplotypes cox1 ont été déterminés chez quinze cestodes du Lynx d’Eurasie (Lynx lynx) de trois localités du sud de la Finlande. En outre, la première étude inter-populationnelle de S. erinaceieuropaei basée sur les données actuellement obtenues sur cox1 de Finlande et sur des données précédemment publiées de Finlande, Lettonie, Ukraine et Pologne, a été réalisée. Le réseau d’haplotypes a montré un motif en étoile sans subdivision spécifique des lignées selon la localité. Des échantillons de Finlande, Lettonie et Pologne partagent plusieurs haplotypes et forment la lignée commune de la Baltique. L’haplotype de S. erinaceieuropaei d’Ukraine est unique et placé sur une voie de mutation distincte suggérant une lignée différente du parasite.

• Keywords
• Food/water-borne zoonosis, Genetic lineages, Molecular genotyping, Sparganosis in Finland, cox1 haplotypes,
• MeSH
• Phylogeny MeSH
• DNA, Mitochondrial genetics   MeSH
• Sparganosis * veterinary   MeSH
• Spirometra * genetics   MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Geographicals
• Europe MeSH
• Names of Substances
• DNA, Mitochondrial MeSH

The large-sized tapeworm Dibothriocephalus latus is known as the broad or fish-borne cestode of mammals that is capable to infect humans and cause diphyllobothriosis. Recently, molecular data on D. latus has been accumulating in the literature and a complete genome sequence has been published; however, little is known about the karyotype and chromosome architecture. In this study, an in-depth karyological analysis of 2 D. latus specimens was carried out. The plerocercoids originated from a perch caught in subalpine Lake Iseo (Italy) and the tapeworms were reared in hamsters. Both specimens contained cells with a highly variable number of chromosomes ranging from18 to 27. Nevertheless, the largest portion of mitotic figures (47%) showed a number corresponding to the triploid set, 3n = 27. Accordingly, the karyotype of the analyzed specimens consisted of 9 triplets of metacentric chromosomes. Fluorescence in situ hybridization (FISH) with the 18S rDNA probe clearly demonstrated the presence of 3 clusters of hybridization signals on the triplet of chromosome 7, thus confirming the triploid status of the specimens. FISH with a telomeric (TTAGGG)n probe confined hybridization signals exclusively to the terminal chromosomal regions, supporting the earlier findings that this repetitive motif is a conserved feature of tapeworm telomeres.

• Keywords
• 18S rDNA, parthenogenesis, polyploidization, telomeres, triploid,
• MeSH
• Chromosomes genetics   MeSH
• Cytogenetic Analysis MeSH
• Diphyllobothriasis parasitology   MeSH
• Diphyllobothrium genetics   metabolism   MeSH
• In Situ Hybridization, Fluorescence MeSH
• Karyotype MeSH
• RNA, Helminth analysis   MeSH
• RNA, Ribosomal, 18S analysis   MeSH
• Triploidy * MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Names of Substances
• RNA, Helminth MeSH
• RNA, Ribosomal, 18S MeSH

BACKGROUND: The systematic of several marine diphyllobothriid tapeworms of pinnipeds has been revised in recent years. However, 20 species of Diphyllobothrium from phocids and otariids are still recognized as incertae sedis. We describe a new species of Diphyllobothrium from the intestine of California sea lions Zalophus californianus (Lesson) (type-host) and South American sea lions Otaria flavescens (Shaw). METHODS: Zalophus californianus from the Pacific coast of the USA and O. flavescens from Peru and Argentina were screened for parasites. Partial fragments of the large ribosomal subunit gene (lsrDNA) and the cytochrome c oxidase subunit 1 (cox1) mitochondrial gene were amplified for 22 isolates. Properly fixed material from California sea lions was examined using light and scanning electron microscopy. RESULTS: A total of four lsrDNA and 21 cox1 sequences were generated and aligned with published sequences of other diphyllobothriid taxa. Based on cox1 sequences, four diphyllobothriid tapeworms from O. flavescens in Peru were found to be conspecific with Adenocephalus pacificus Nybelin, 1931. The other newly generated sequences fall into a well-supported clade with sequences of a putative new species previously identified as Diphyllobothrium sp. 1. from Z. californianus and O. flavescens. A new species, Diphyllobothrium sprakeri n. sp., is proposed for tapeworms of this clade. CONCLUSIONS: Diphyllobothrium sprakeri n. sp. is the first diphyllobothriid species described from Z. californianus from the Pacific coast of North America, but O. flavescens from Argentina, Chile and Peru was confirmed as an additional host. The present study molecularly confirmed the first coinfection of two diphyllobothriid species in sea lions from the Southern Hemisphere.

• Keywords
• Helminths, Otaria flavescens, Otariidae, Parasites, Pinnipedia, Zalophus californianus, cox1, lsrDNA,
• MeSH
• Diphyllobothriasis veterinary   MeSH
• Diphyllobothrium anatomy & histology   classification   genetics   isolation & purification   MeSH
• Phylogeny MeSH
• Sea Lions parasitology   MeSH
• Genes, Mitochondrial MeSH
• Intestines parasitology   MeSH
• Animals MeSH
• Check Tag
• Male MeSH
• Female MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Geographicals
• South America MeSH
• North America MeSH