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Parasitology Research Dec 2012Hysterothylacium zhoushanensis sp. nov. collected from the intestine of the flatfish Pseudorhombus oligodon (Bleeker) (Pleuronectiformes: Paralichthyidae) in the East...
Morphological and genetic characterization of Hysterothylacium zhoushanensis sp. nov. (Ascaridida: Anisakidae) from the flatfish Pseudorhombus oligodon (Bleeker) (Pleuronectiformes: Paralichthyidae) in the East China Sea.
Hysterothylacium zhoushanensis sp. nov. collected from the intestine of the flatfish Pseudorhombus oligodon (Bleeker) (Pleuronectiformes: Paralichthyidae) in the East China Sea is described and illustrated by light and scanning electron microscopy. The new species can be easily distinguished from its congeners by the presence of remarkable lateral alae, the very short intestinal caecum, the unusually long ventricular appendix (ratio of intestinal caecum to ventricular appendix 1:8.74-23.8), the short spicules (0.58-0.81 mm long, representing 1.70-2.08 % of body length) and the number and arrangement of male caudal papillae (35-42 pairs in total, arranged as 26-32 pairs of precloacal, two pairs of paracloacal and six to eight pairs of postcloacal). In addition, the adults and the putative third-stage larvae identified morphologically of the new species are characterised by sequencing and analysing the internal transcribed spacer (ITS) of the ribosomal DNA. The result reveals that they are homogeneous genetically, and all belong to the same species. Molecular analysis by comparing the ITS gene of H. zhoushanensis sp. nov. with these species of Hysterothylacium available in GenBank also seem to support the validity of the new species based on the morphological observation.
Topics: Animals; Aquatic Organisms; Ascaridoidea; China; DNA, Helminth; DNA, Ribosomal Spacer; Flatfishes; Gastrointestinal Tract; Microscopy; Molecular Sequence Data; Seawater; Sequence Analysis, DNA
PubMed: 22955500
DOI: 10.1007/s00436-012-3095-3 -
Parasitology Feb 2024Species of (Nematoda: Ascarididae) are of great veterinary and zoonotic significance, owing to cause Baylisascariosis or Baylisascariasis in wildlife, captive animals...
Morphology and ASAP analysis of the important zoonotic nematode parasite (Stefahski and Zarnowski, 1951), with molecular phylogenetic relationships of species (Nematoda: Ascaridida).
Species of (Nematoda: Ascarididae) are of great veterinary and zoonotic significance, owing to cause Baylisascariosis or Baylisascariasis in wildlife, captive animals and humans. However, the phylogenetic relationships of the current 10 species remain unclear. Moreover, our current knowledge of the detailed morphology and morphometrics of the important zoonotic species is still insufficient. The taxonomical status of and remains under debate. In the present study, the detailed morphology of was studied using light and scanning electron microscopy based on newly collected specimens from the raccoon (Linnaeus) in China. The results of the ASAP analysis and Bayesian inference (BI) using the 28S, ITS, 1 and 2 genetic markers did not support that and represent two distinct species. Integrative morphological and molecular assessment challenged the validity of , and suggested that seems to represent a synonym of Molecular phylogenetic results indicated that the species of were grouped into 4 clades according to their host specificity. The present study provided new insights into the taxonomic status of and preliminarily clarified the phylogenetic relationships of species.
Topics: Animals; Humans; Ascaridida; Phylogeny; Parasites; Bayes Theorem; Ascaridoidea; Raccoons
PubMed: 38087962
DOI: 10.1017/S0031182023001312 -
Advances in Parasitology 2020This review describes the morphology and ultrastructure of the third-stage larva of Toxocara canis, the larval stage that hatches from the egg and persists in the... (Review)
Review
This review describes the morphology and ultrastructure of the third-stage larva of Toxocara canis, the larval stage that hatches from the egg and persists in the tissues of various paratenic hosts including infected humans. This larva remains unchanged as it passes from host to host and lives for extended periods in this same body form until it makes its way to the gastro-intestinal tract of its final host. There has been less work on the anatomy and ultrastructure of the larva of Toxocara cati, but overall, it appears very similar to that of T. canis with the only apparent difference being that the larva is a few microns thinner in diameter. The paper describes the anatomy and ultrastructure of the larva and the various major structures of the various body systems including the cuticle, hypodermis, the nervous tissue, oesophagus and the lumen-free intestine, and the large excretory gland cell that fills much of the pseudocoel and which appears to be the source of the components that are recognized immunologically by the infected host. It is suggested that further detailed studies on the larva could provide significant information that would allow a greater understanding of how the larva persists within these hosts and may provide information that would make the larva an excellent link to work on nematode anatomy that would link the work being done with this model system to that of Caenorhabditis elegans and the large amount of historical work already performed on adult ascaridoid nematodes.
Topics: Animals; Humans; Larva; Toxocara; Toxocara canis
PubMed: 32381209
DOI: 10.1016/bs.apar.2020.03.002 -
Parasitology Oct 1986The genetic structure of Anisakis physeteris from the Mediterranean Sea has been analysed electrophoretically at 22 enzyme loci. The samples studied, although differing...
The genetic structure of Anisakis physeteris from the Mediterranean Sea has been analysed electrophoretically at 22 enzyme loci. The samples studied, although differing in the life-stage (larvae and adults), and in the host (the fishes Micromesistius poutassou and Trachurus trachurus, and the sperm whale Physeter macrocephalus) were genetically homogeneous. Of these loci 11 (Ldh, Sod, Np, Adk-2, Pgm-1, Est-1, Est-2, Acph-1, Acph-2, Lap-2 and Ca) were found to be monomorphic, while the other 11 (Sdh, Mdh, Idh, 6-Pgdh, G3pdh, Got, Adk-1, Pgm-2, Lap-1, Mpi and Gpi) showed from 2 to 7 alleles. The following values of genetic variability were estimated: He = 0.11, P = 0.50, A = 1.95. Distinct alleles were found between A. physeteris and the A. simplex complex at 19 out of the 22 loci studied, and only few rare alleles were shared at the remaining 3 loci. The genetic divergence between A. physeteris and A. simplex A and B is therefore very high, the values of Nei's index D being 7.384 and 6.443 respectively (I = 0.001 and 0.002). The assignation of A. physeteris and the A. simplex complex to two distinct subgenera, Skrjabinisakis and Anisakis, as proposed by Mosgovoy on a morphological basis, appears to be fully justified according to our genetic data.
Topics: Alleles; Animals; Ascaridoidea; Cetacea; Electrophoresis; Fish Diseases; Fishes; Isoenzymes; Mediterranean Sea; Nematode Infections; Whales
PubMed: 3785976
DOI: 10.1017/s0031182000051544 -
Parasitology Research Apr 2014The tanaka's snailfish Liparis tanakae (Gilbert & Burke) (Scorpaeniformes: Liparidae) is an economically important marine fish species in China. However, the helminth...
The tanaka's snailfish Liparis tanakae (Gilbert & Burke) (Scorpaeniformes: Liparidae) is an economically important marine fish species in China. However, the helminth parasites of this fish are still poorly known. During a helminthological survey of Chinese marine fishes from 2011 to 2012, we revealed that L. tanakae was heavily infected with third-stage larvae and adults of ascaridoid nematodes (total prevalence 100% and mean intensity 82.3 nematodes per fish). Four species of third-stage larvae Hysterothylacium liparis Li, Xu & Zhang, 2007, H. aduncum (Rudolphi, 1802), Hysterothylacium fabri (Rudolphi, 1819), and Anisakis pegreffii (Campana-Rouget & Biocca, 1955) and a single species of adults H. liparis were differentiated and identified by morphological and molecular methods. The detailed morphology of the four species of third-stage larvae was also studied using light microscopy and scanning electron microscopy. The morphological and molecular characterization of the third-stage larvae of H. liparis was reported. Liparis tanakae represents a new host record for A. pegreffii and H. fabri. In addition, a new name, Hysterothylacium zhoushanense nom. nov. was also given to Hysterothylacium zhoushanensis Li, Liu & Zhang, 2012 to make the latinized specific epithet agree with this neuter generic name.
Topics: Animals; Anisakiasis; Anisakis; Ascaridida Infections; Ascaridoidea; China; DNA, Ribosomal Spacer; Female; Fishes; Larva; Male
PubMed: 24464274
DOI: 10.1007/s00436-014-3767-2 -
The Journal of Parasitology Aug 2007Aplectana tarija n. sp. and Cosmocercoides lilloi n. sp., intestinal parasites of the toad Chaunus arenarum, are described. Of the 41 nominal species of Aplectana, A....
Aplectana tarija n. sp. and Cosmocercoides lilloi n. sp., intestinal parasites of the toad Chaunus arenarum, are described. Of the 41 nominal species of Aplectana, A. tarija n. sp. represents the 22nd Neotropical species and the second species reported from Argentina. Of the 14 nominal species of Cosmocercoides, C. lilloi n. sp. represents the 15th species and the first species reported from South America.
Topics: Animals; Argentina; Ascaridida; Ascaridida Infections; Bufo arenarum; Female; Intestinal Diseases, Parasitic; Intestine, Large; Male; Prevalence
PubMed: 17918375
DOI: 10.1645/GE-1131R.1 -
Acta Parasitologica Mar 2014Toxascaris leonina (Linstow, 1902) is a most common intestinal parasite of various animals in Felidae and Canidae. In the present paper, light and scanning electron...
Toxascaris leonina (Linstow, 1902) is a most common intestinal parasite of various animals in Felidae and Canidae. In the present paper, light and scanning electron microscopy (SEM) were used to study the morphological aspects of adult worms of this nematode in detail, based on the material collected from Panthera leo (Linnaeus) and Felis lynx (Linnaeus) (Carnivora: Felidae) in China. The results showed that there were some morphometric differences between the present material and the previous studies, including the body size, the width and length of cervical alae, the number of denticles on each lip and the tail length of the female. Previously unreported morphological features were also revealed. These supplementary morphological and morphometric data contributed to a more accurate identification of this worldwide distributed ascarid nematode.
Topics: Animal Structures; Animals; Biometry; China; Female; Lions; Lynx; Male; Microscopy; Toxascaris
PubMed: 26204033
DOI: 10.1515/ap-2015-0020 -
Parasitology Research Jul 2016Strongyluris calotis is a heterakid nematode in the large intestine of agamid lizards (Reptilia: Sauria: Agamidae) from the Oriental Region. The standard light...
Strongyluris calotis is a heterakid nematode in the large intestine of agamid lizards (Reptilia: Sauria: Agamidae) from the Oriental Region. The standard light microscopic definition of the species counts the "caudal papillae" as 10 pairs on male worms. However, previous work from our group using scanning electron microscopy (SEM) on the heterakid from agamid lizards in Japan, Taiwan, and Singapore revealed that this counting contained a pair of phasmids and that two pairs of postcloacal papillae were completely fused to form a pair of united papillae, thus resulting in "10 pairs." In the present study, we examined S. calotis specimens from the Emma Gray's forest lizard, Calotes emma (Agamidae), living in the plain forest at low altitude, and the Vietnam false bloodsucker, Pseudocalotes brevipes (Agamidae), living in the mountainous forest at high altitude in the northern part of Vietnam. Using SEM, the arrangement of caudal papillae in male worms from an Emma Gray's forest lizard was found to be comparable to classical S. calotis specimens from agamid lizards collected in Japan, Taiwan, and Singapore. However, male worms from Vietnam false bloodsuckers did not have a pair of united papillae but had 10 pairs of independent caudal papillae with a pair of phasmids. Molecular genetic analyses of the ribosomal RNA gene (rDNA) of worms of the classical S. calotis morphotype from Japan and Singapore and two S. calotis morphotypes from Vietnam demonstrated absolutely identical nucleotide sequences of partial 18S rDNA (at least 1764 base pairs (bp)) and 5.8S rDNA (158 bp). However, intraspecific differences were detected in other regions of the rDNA, related to the geographical distribution of hosts regardless of morphotype: 97.8-98.5 % identity (443-446 bp/453 bp) in the internal transcribed spacer (ITS)-1 region, 96.6-98.0 % identity (425-431 bp/440 bp) in the ITS-2 region, and 99.6-99.7 % identity (1149-1151 bp/1154 bp) in the 28S rDNA. Thus, in the future, taxonomic relationships of S. calotis distributed widely in the Oriental Region as well as other nominal Oriental Strongyluris spp., currently six in number, need to be extensively explored based on molecular genetic analyses in addition to intensive morphological characterization.
Topics: Animals; Ascaridida; Base Sequence; DNA, Ribosomal; Female; Genetic Variation; Intestine, Large; Lizards; Male; Vietnam
PubMed: 27041339
DOI: 10.1007/s00436-016-5030-5 -
Journal of Helminthology Dec 1986The relationships between larvae and adults of Anisakis from the Mediterranean Sea and North-East Atlantic Ocean were analysed by multilocus electrophoresis. The...
The relationships between larvae and adults of Anisakis from the Mediterranean Sea and North-East Atlantic Ocean were analysed by multilocus electrophoresis. The correspondence of type I larvae with the A. simplex complex, including the sibling species A. simplex A and B, and of type II larvae with A. physeteris is confirmed. 19 of the 22 loci studied discriminated between the two larval types. Biochemical keys are given for the electrophoretic identification of A. simplex A, A. simplex B and A. physeteris, at both the larval and adult stages.
Topics: Animals; Ascaridoidea; Atlantic Ocean; Decapodiformes; Dolphins; Electrophoresis, Starch Gel; Fishes; Larva; Mediterranean Sea; Whales
PubMed: 3794297
DOI: 10.1017/s0022149x00008580 -
Folia Parasitologica Dec 2014Ophidascaris wangi sp. n. collected from the king rat snake Elaphe carinata (Günther) (Serpentes: Colubridae) in China is described using both light and scanning...
Ophidascaris wangi sp. n. collected from the king rat snake Elaphe carinata (Günther) (Serpentes: Colubridae) in China is described using both light and scanning electron microscopy. The new species differs from its congeners in the presence of narrow lateral alae originating a short distance posterior to the base of the ventrolateral lips, its relatively long oesophagus (3.57-4.54 mm long, representing 6.6-7.6% of body length), its short spicules (1.89-2.14 mm long, representing 3.9-4.3% of body length), the number and arrangement of caudal papillae (49-57 pairs in total, arranged as follows: 43-51 pairs precloacal, 2 pairs joined paracloacal and 4 pairs postcloacal), the presence of a particular papilliform medioventral, postcloacal ornamentation and the morphology of the eggs and tip of the female tail. In addition, Ophidascaris najae (Gedoelst, 1916), collected from the king cobra Ophiophagus hannah Cantor (Serpentes: Elapidae) in China, is also redescribed. The morphology of the cervical papillae, labial denticles and phasmids of the female is described for the first time.
Topics: Animals; Ascaridida Infections; Ascaridoidea; China; Female; Male; Snakes
PubMed: 25651700
DOI: No ID Found