BACKGROUND: The family Toxocaridae is a group of zooparasitic nematodes of veterinary, medical and economic significance. However, the evolutionary relationship of Porrocaecum and Toxocara, both genera currently classified in Toxocaridae, and the monophyly of the Toxocaridae remain under debate. Moreover, the validity of the subgenus Laymanicaecum in the genus Porrocaecum is open to question. Due to the scarcity of an available genetic database, molecular identification of Porrocaecum nematodes is still in its infancy. METHODS: A number of Porrocaecum nematodes collected from the Eurasian marsh harrier Circus aeruginosus (Linnaeus) (Falconiformes: Accipitridae) in the Czech Republic were identified using integrated morphological methods (light and scanning electron microscopy) and molecular techniques (sequencing and analyzing the nuclear 18S, 28S and ITS regions). The complete mitochondrial genomes of the collected nematode specimens and of Porrocaecum (Laymanicaecum) reticulatum (Linstow, 1899) were sequenced and annotated for the first time. Phylogenetic analyses of ascaridoid nematodes based on the amino acid sequences of 12 protein-coding genes of mitochondrial genomes were performed using maximum likelihood and Bayesian inference. RESULTS: A new species of Porrocaecum, named P. moraveci n. sp., is described based on the morphological and genetic evidence. The mitogenomes of P. moraveci n. sp. and P. reticulatum both contain 36 genes and are 14,517 and 14,210 bp in length, respectively. Comparative mitogenomics revealed that P. moraveci n. sp. represents the first known species with three non-coding regions and that P. reticulatum has the lowest overall A + T content in the mitogenomes of ascaridoid nematodes tested to date. Phylogenetic analyses showed the representatives of Toxocara clustered together with species of the family Ascarididae rather than with Porrocaecum and that P. moraveci n. sp. is a sister to P. reticulatum. CONCLUSIONS: The characterization of the complete mitochondrial genomes of P. moraveci n. sp. and P. reticulatum is reported for the first time. Mitogenomic phylogeny analyses indicated that the family Toxocaridae is non-monophyletic and that the genera Porrocaecum and Toxocara do not have an affinity. The validity of the subgenus Laymanicaecum in Porrocaecum was also rejected. Our results suggest that: (i) Toxocaridae should be degraded to a subfamily of the Ascarididae that includes only the genus Toxocara; and (ii) the subfamily Porrocaecinae should be resurrected to include only the genus Porrocaecum. The present study enriches the database of ascaridoid mitogenomes and provides a new insight into the systematics of the superfamily Ascaridoidea.

• Klíčová slova
• Ascaridomorpha, Birds, Integrated taxonomy, Mitochondrial genome, New species, Parasitic nematodes, Phylogeny,
• MeSH
• Ascaridoidea * genetika   MeSH
• Bayesova věta MeSH
• biologická evoluce MeSH
• fylogeneze MeSH
• genom mitochondriální * MeSH
• ptáci genetika   MeSH
• Toxocara genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• dopisy MeSH

Trichuris sp. individuals were collected from Myocastor coypus from fancy breeder farms in the Czech Republic. Using morphological and biometrical methods, 30 female and 30 male nematodes were identified as Trichuris myocastoris. This paper presents the first molecular description of this species. The ribosomal DNA (rDNA) region, consisting of internal transcribed spacer (ITS)-1, 5.8 gene and ITS-2, was sequenced. Based on an analysis of 651 bp, T. myocastoris was found to be different from any other Trichuris species for which published sequencing of the ITS region is available. The phylogenetic relationships were estimated using the maximum parsimony methods and Bayesian analyses. T. myocastoris was found to be significantly closely related to Trichuris of rodents than those of ruminants.

• Klíčová slova
• ITS1-5.8S-ITS2, Myocastor coypus, Parasites, Trichuris myocastoris, rDNA,
• MeSH
• Bayesova věta MeSH
• DNA helmintů chemie   genetika   MeSH
• fylogeneze MeSH
• lidé MeSH
• mezerníky ribozomální DNA chemie   genetika   MeSH
• ribozomální DNA chemie   genetika   MeSH
• sekvence nukleotidů MeSH
• trichurióza epidemiologie   veterinární   virologie   MeSH
• Trichuris * anatomie a histologie   klasifikace   genetika   izolace a purifikace   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Česká republika epidemiologie   MeSH
• Názvy látek
• DNA helmintů MeSH
• mezerníky ribozomální DNA MeSH
• ribozomální DNA MeSH

Trichuris nematodes were isolated from roe deer (Capreolus capreolus). At first, nematodes were determined using morphological and biometrical methods. Subsequently genomic DNA was isolated and the ITS1-5.8S-ITS2 segment from ribosomal DNA (RNA) was amplified and sequenced using PCR techniques. With u sing morphological and biometrical methods, female nematodes were identified as Trichuris globulosa, and the only male was identified as Trichuris ovis. The females were classified into four morphotypes. However, analysis of the internal transcribed spacers (ITS1-5.8S-ITS2) of specimens did not confirm this classification. Moreover, the female individuals morphologically determined as T. globulosa were molecularly identified as Trichuris discolor. In the case of the only male molecular analysis match the result of the molecular identification. Furthermore, a comparative phylogenetic study was carried out with the ITS1 and ITS2 sequences of the Trichuris species from various hosts. A comparison of biometric information from T. discolor individuals from this study was also conducted.

• MeSH
• DNA helmintů chemie   genetika   MeSH
• fylogeneze MeSH
• mezerníky ribozomální DNA chemie   genetika   MeSH
• mikroskopie MeSH
• molekulární sekvence - údaje MeSH
• ribozomální DNA chemie   genetika   MeSH
• RNA ribozomální 5.8S genetika   MeSH
• sekvenční analýza DNA MeSH
• shluková analýza MeSH
• trichurióza parazitologie   veterinární   MeSH
• Trichuris anatomie a histologie   klasifikace   genetika   izolace a purifikace   MeSH
• vysoká zvěř parazitologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA helmintů MeSH
• mezerníky ribozomální DNA MeSH
• ribozomální DNA MeSH
• RNA ribozomální 5.8S MeSH

Polymerase chain reaction-restriction fragment length polymorphism) was performed on the cistron of rDNA in the two groups of infective larvae Trichostrongylus colubriformis-the population with and without ability to undergo arrested development. General primers designed by Caenorhabditis elegans rDNA were used for the amplification of the rDNA cistron between genes 18S and 28S. Amplified fragments were digested by using a series of restriction endonucleases. Hinc II restriction profiles unique for each T. colubriformis populations were observed, and therefore enzyme Hinc II appears to be useful for the determination of populations with and without the ability to undergo arrested development. Molecular markers of arrested development ability have not been studied on this part of rDNA before.

• MeSH
• chov zvířat MeSH
• DNA helmintů analýza   MeSH
• kozy MeSH
• larva genetika   růst a vývoj   MeSH
• nemoci koz parazitologie   MeSH
• polymerázová řetězová reakce MeSH
• polymorfismus délky restrikčních fragmentů MeSH
• polymorfismus genetický * MeSH
• restrikční endonukleasy typu II metabolismus   MeSH
• ribozomální DNA genetika   MeSH
• RNA ribozomální 18S genetika   MeSH
• RNA ribozomální 28S genetika   MeSH
• trichostrongylóza parazitologie   veterinární   MeSH
• Trichostrongylus klasifikace   genetika   růst a vývoj   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• hodnotící studie MeSH
• práce podpořená grantem MeSH
• Názvy látek
• DNA helmintů MeSH
• GTYRAC-specific type II deoxyribonucleases MeSH Prohlížeč
• restrikční endonukleasy typu II MeSH
• ribozomální DNA MeSH
• RNA ribozomální 18S MeSH
• RNA ribozomální 28S MeSH