Systematic Parasitology最新文献

The Indian species of the genus Canalirogas van Achterberg & Chen, 1996 are revised. Four new species, Canalirogas multinigratus Gupta & van Achterberg sp. nov. and C. subtransversus Gupta & van Achterberg sp. nov. from Meghalaya (north-eastern India); C. oblongus Gupta & van Achterberg sp. nov. from Assam (north-eastern India) and Canalirogas omninopallidus Gupta & van Achterberg sp. nov. from Karnataka (southern India) are illustrated and described. An illustrated key to the Indian species of Canalirogas is provided.

Pulmovermis cyanovitellosus Coil and Kuntz, 1960 is a species of hemiurid trematode that localizes in the lung of sea snakes, an unusual trait for this group of parasites. Recent molecular phylogenetic studies based on 28S rRNA gene sequences have shown that this species is closely related to members of the genus Lecithochirium Lühe, 1901. This finding is unexpected given that Pulmovermis Coil and Kuntz, 1960 and Lecithochirium are currently classified in different subfamilies of Hemiuridae (Pulmoverminae Sandars, 1961 vs. Lecithochiriinae Lühe, 1901). To investigate this discrepancy, we conducted a comparative morphological study on new specimens of P. cyanovitellosus collected from the same locality as those in our previous research. These new specimens were compared with the paragenophores from our earlier study and with existing descriptions in literatures. This study provides the following new morphological data regarding P. cyanovitellosus: body surface covered with minute scales; massive muscular pads present on both sides of body at level of terminal genitalia; small esophageal pouch and Drüsenmagen present; seminal vesicle connecting to pars prostatica via aglandular duct; small, cylindrical sinus-sac present; ejaculatory vesicle absent; Juel's organ present; metraterm separated from uterus by conspicuous sphincter and connecting to distal end of pars prostatica. Additionally, we assessed the phylogenetic relationships of P. cyanovitellosus using the 28S rRNA gene, the internal transcribed spacer 2 (ITS2), and the cytochrome c oxidase subunit I (COI) gene markers. Phylogenetic analyses based on these markers demonstrated that P. cyanovitellosus clustered with species of Lecithochirium. Based on this molecular evidence, we conclude that Pulmovermis is a junior synonym of the genus Lecithochirium, and propose L. cyanovitellosum (Coil and Kuntz, 1960) Urabe and Sokolov comb. nov. Given the morphological similarities between Pulmovermis and Hydrophitrema Sandars, 1960, we also propose synonymizing the latter with Lecithochirium, and L. giganticum (Sandars, 1960) Urabe and Sokolov comb. nov. and L. pingtanense (Wang, 1980) Urabe and Sokolov comb. nov. are proposed. As a result, Pulmoverminae should be considered a junior synonym of Lecithochiriinae Lühe, 1901.

The nutria (Myocastor coypus) is a semiaquatic rodent that originally inhabited South America. However, the animals have spread to different continents as alien species, and their numbers are quickly increasing, especially in North America, Europe, and Eastern Asia including Japan. Although nutrias have been suggested to serve as reservoirs for pathogens, including parasites, there have been few reports on this subject. In the present study, we surveyed the gastrointestinal parasites in nutrias living in Japan to better understand their prevalence in nutrias. We collected 72 samples of intestinal contents or feces from nutrias in Osaka and Okayama Prefectures. We found that 49 (68.1 %) samples were positive for Eimeria parasites, and two types of oocysts were identified: ellipsoidal (Type A) and subspherical (Type B) oocysts. In addition, Strongyloides myopotami was detected in 44 samples, and Capillaria spp. and Fasciola spp. were detected in one and three samples, respectively. Based on the morphologies of the detected Eimeria oocysts, Types A and B were identified to be E. coypi and E. fluviatilis, respectively. Phylogenetic analyses after PCR and sequencing targeting the cytochrome c oxidase subunit I gene placed the sequences of E. fluviatilis (Type B) as a cluster between the sequences of Eimeria derived from rodents. The sequences of the three subgenotypes of E. coypi (Type A) were included in the cluster containing the sequences of Eimeria spp. from rodents of multiple species, which is referred to as the Apionodes supercluster, and is separate from other clades. It has been suggested that Eimeria spp. from rodents in this cluster can quickly adapt to infect different hosts. Although further analyses are needed to construct more detailed phylogenetic trees, our results revealed the genetical positions of Eimeria spp. in nutrias. In addition, our results may be helpful when considering host specificity as well as host switching by the pathogen.

Opistholecithum sandugaense n. g. n. sp. was collected from the intestine of Oncorhynchus keta (Walbaum) in the Nezhinka (=Sanduga) River, Primorsky region, Russia. Based on the position of the vitellarium in hindbody and significant genetic differentiation, ten species from the genus Lecithaster Lühe, 1901 were transferred to the newly established Opistholecithum as follows: O. gibbosum (Rudolphi, 1802) n. comb., O. macrocotyle (Szidat & Graefe, 1967) n. comb., O. micropsi (Zdzitowiecki, 1992) n. comb., O. salmonis (Yamaguti, 1934) n. comb. According to the morphometrics and topology of the internal organs, O. sandugaense appears similar to O. salmonis. These species are distinct based on novel sequence data - 28S rRNA gene (p-distances 0.4%) and the cox1 mtDNA gene (p-distances 4.4-4.8%). Large-scale phylogeny reconstruction showed that the lecithasterid subfamily Lecithasterinae sensu stricto include two genera Lecithaster (type taxon) and Opistholecithum n. g.; other genera Lecithophyllum and Aponurus were transferred to the family Lecithophyllidae n. stat. Based on the morphological features, we consider four subfamilies Lecithasterinae, Trifoliovariinae, Prolecithinae and Macradenininae belonging to Lecithasteridae. Analysis of indels in the 28S divergent domains proved to be a robust technic for family delimitation within the superfamily Hemiuroidea. Especially it allows to reveal the molecular symplesiomorphies affecting phylogenetic reconstructions. Taxonomic rearrangements proposed in this study are supplemented by dichotomous keys: (1) for two genera of the subfamily Lecithasterinae; (2) for the genus Opistholecithum; (3) for the genus Lecithaster; (4) for six closely related hemiuroid families, with Lecithophyllidae n. stat. (genera Lecithophyllum, Aponurus, Monorchiaponurus, Weketrema) and Merlucciotrematidae n. fam. (Merlucciotrema).

Corynosoma pseudohamanni Zdzitowiecki, 1984 (Polymorphidae) was described from the intestinal tract of 5 species of seals including the type and main host, the Weddell seal Leptonycotes weddellii (Lesson) in the South Shetlands, West Antarctica. Notothenia coriiceps was the primary paratenic host of 14 fish hosts reported in the original description. We describe excysted juveniles from the body cavity of the major paratenic host, Notothenia coriiceps Richardson collected off Galindez Island, Argentine Islands, West Antarctica for the first time. The original description was not "based on material collected from the final hosts (seals) and paratenic hosts (fish)" as stated since no description of juveniles was given then. Our excysted juveniles were generally smaller than reported adults and many of the other measurements were comparable to those of the adults in the original description. We added many of the incomplete measurements of adults in the original description especially those of the underdeveloped reproductive structures. We compared our morphometric description with the only other one available for juveniles collected from three paratenic fish hosts from Prince Gustav Channel, Antarctica. We have added informative optical microscopy images and SEM images of internal and external structures, previously missed in the original description. Energy Dispersive X-ray analysis revealed the highest levels of calcium in all hooks and hook roots compared to sulfur and phosphorus. We also provide a molecular characterization of the species for the first time. Newly generated sequences of the mitochondrial cytochrome c oxidase subunit 1 (mtcox1) gene from isolates of C. pseudohamanni cystacanths were compared with sequences of other acanthocephalans available in GenBank. Phylogenetic analyses based on maximum likelihood (ML) and Bayesian inference (BI) methods of the cox1 dataset placed all the species of Corynosoma in a single clade, with strong support. The mt cox1 sequences of C. pseudohamanni formed a strongly supported individual clade with the published sequences of Corynosoma nortmeri and Corynosoma magdaleni from the North Sea, Germany. We have determined the genetic diversity of C. pseudohamanni and compare it with other Corynosoma species haplotype diversity and distribution.

The Neotropical bat-ectoparasite family Spelaeorhynchidae comprises seven species into in one genus. The species Spelaeorhynchus praecursor is the most distributed in the region, parasitizing phyllostomid bats of the subfamilies Carolliinae, Glossophaginae and Stenodermatinae. The present study expands the known geographic distribution of this species, providing new host records, as well as the first SEM images detailing the main characteristics of this species.

A new ascaridoid nematode, Hysterothylacium malleocaudatum sp. n., was described using both light and scanning electron microscopy, based on specimens collected from the greater amberjack Seriola dumerili (Risso) (Carangiformes: Carangidae) in the Persian Gulf off Iraq. The new species can be distinguished from the congeners by the combination of the following features, the presence of remarkable lateral alae starting from base of ventro-lateral lips, the short intestinal caecum and long ventricular appendix (intestinal caecum representing 21.1-40.5% of oesophageal length, ratio of intestinal caecum to ventricular appendix 1: 1.42-3.77), the relatively long oesophagus (oesophageal length representing 9.83-14.3 % body length), the number and arrangement of the caudal papillae (31-37 pairs precloacal, 1-2 pairs paracloacal and 6 pairs postcloacal), and the presence of inflated hammer-shaped tail tip in both sexes. The new species represents the fourth Hysterothylacium species reported in marine fishes from Persian Gulf, off Iraq.

A comprehensive checklist of monogenean parasites from marine fish in Algeria was compiled by reviewing the entire available literature, resulting in a detailed parasite-host and host-parasite list. This checklist includes 156 species across 71 genera and 23 families of monogeneans, with 136 species identified to the species level, while the remaining 20 species are identified only to the genus (19 species) or subfamily level (1 species). These parasites have been reported from 82 marine fish hosts, spanning 34 families: 15 species of Elasmobranchii, 1 of Holocephali, and 66 of Teleostei. The highest number of monogenean species was found on Teleostei (128), followed by Elasmobranchii (26), and Holocephali (2). The family Diplectanidae Monticelli, 1903 is the most prevalent, encompassing 43 species, followed by Microcotylidae Taschenberg, 1879 with 27 species. Among the most diverse genera are Lamellodiscus Johnston & Tiegs, 1922 and Microcotyle Van Beneden & Hesse, 1863, with the latter's species, Microcotyle erythrini, Van Beneden & Hesse, 1863 being the most encountered species. The class Teleostei has been the most extensively studied, with the Sparidae Rafinesque, 1818 family receiving the most attention, particularly Boops boops (Linnaeus) as the most cited fish species. Notably, Diplodus vulgaris (Geoffroy Saint-Hilaire) and Diplodus sargus (Linnaeus) exhibit high species richness. The checklist also identified seven Monogenea species, including Atriaster maillardi López-Román & De Armas Hernández, 1989, newly recorded in the Mediterranean. This checklist provides an up-to-date summary of Monogenea diversity in Algerian marine fish, reflecting nearly three decades of detailed taxonomic research. It highlights the current understanding of these parasites and underscores the need for continued research to fully explore the diversity of monogenean parasites in Algerian fish fauna.

Trochopus martydeveneyi n. sp., a large, elegant species is described from the dorsal surface of the pectoral fins of captive Cape gurnard, Chelidonichthys capensis (Cuvier), at Two Oceans Aquarium, Cape Town, originally collected from Table Bay, South Africa in 2007. The host microhabitat for T. martydeveneyi n. sp. is uncharacteristic for Trochopus species, which are generally known from the gills, and less so from the skin of the body of their hosts. This new species is unique among the known Trochopus species, possessing a large, dark-staining gland on each of the two testes, presumably to produce the contents of the spermatophore plug that is visible in the vagina of two specimens. Two separate individual specimens of T. martydeveneyi n. sp. also presented with unilateral testicular atrophy, which is apparently rare in the Monogenea but considered a natural occurrence. Egg hatching and larval haptoral morphology are also provided. Trochopus lawleri n. sp. is proposed for Trochopus hobo sensu Lawler and Hargis (1968) from the gills of Chelidonichthys kumu (Cuvier) off Australia, and the monotypic Trochopella Euzet & Trilles, 1962 is synonymised with Trochopus Diesing, 1850. The generic diagnosis is revised for Trochopus to incorporate new data, and information previously excluded.

A new genus and species within the family Polymorphidae Meyer, 1931 were erected to accommodate cystacanths recovered from the mesentery of individuals from a non-native population of the red swamp crayfish Procambarus clarkii (Girard), collected from South Carolina (USA). Morphological characteristics of the specimens collected included in both sexes a spindle-shaped body with a slender hindtrunk, two fields of markedly different sized spines on the foretrunk, the presence of a middle row of smaller scythe-shaped hooks on a proboscis armed with 19-20 longitudinal rows of 14-16 hooks; and in males, six cement glands, absence of genital spines, and a digitiform and spinose bursa (observed inverted). Sequencing portions of both the mitochondrial cytochrome c oxidase I (COI) and large subunit ribosomal RNA genes was completed, followed by phylogenetic analysis of a concatenated alignment. Sequences from our specimens appeared in a clade with those of Hexaglandula corynosoma (Travassos, 1915) and Ibirhynchus dimorpha (Schmidt, 1973) but were 27% divergent from both using the COI marker. The genetic divergence of this parasite from other polymorphid genera, along with unique morphological features, justified erecting a new genus and new species. Herein we describe Heterospinus mccordi n. gen. n. sp. bringing the total number of genera within the family Polymorphidae to 16, and we emend and update the latest key that was provided for the genera within this family. This is the first record of polymorphids infecting P. clarkii outside of its native range. The definitive host remains unknown.