RESUMO
The tadpole-dwelling pinworm, Gyrinicola batrachiensis (Walton, 1929) Adamson, 1981 was recognized as the sole representative of the genus across Canada and the United States. However, evaluation of the morphology of these parasites across their range revealed considerable morphological variability that suggested diagnosable morphotypes. These morphotypes were associated with different species of anurans, several of which occurred in sympatry. Herein we use an extensive geographic sampling across the United States to obtain the morphotypes, screen their genetic diversity, and analyze this information using an integrative approach. We reconstructed their phylogeny using nuclear ribosomal partial genes 18S and 28S, ITS1, 5.8S, and ITS2, as well as 5 mitochondrial genes generated with Next-Generation sequencing technology. This phylogeny reveals 3 well-resolved lineages, which upon the use of a statistical approach (bPTP [Bayesian implementation of the Poisson tree processes]) supports the delimitation of 4 distinct groups equivalent to species. These putative species groups were tested using morphological characteristics paired with a MANOVA and canonical variate analysis. Results suggest that at least 4 species of Gyrinicola are present within North America, resulting in the resurrection of G. armatus (Walton, 1933) and the description of 2 new species.
Assuntos
Teorema de Bayes , DNA de Helmintos , Variação Genética , Filogenia , Estados Unidos , Animais , DNA de Helmintos/química , Anuros/parasitologia , Oxyuroidea/classificação , Oxyuroidea/genética , Oxyuroidea/anatomia & histologia , RNA Ribossômico 28S/genética , DNA Espaçador Ribossômico/genética , DNA Mitocondrial/química , DNA Mitocondrial/genéticaRESUMO
Triatoma sanguisuga (Leconte) is one of the most widely distributed kissing bugs in the United States, associated with an extensive zoonotic circulation of Trypanosoma cruzi, the agent of Chagas disease, in a large part of the country. However, the actual risk for human infection in the United States is poorly understood. Here, we further assessed the ecology of T. sanguisuga bugs collected in residents' houses in Illinois and Louisiana, using a metagenomic approach to identify their blood-feeding sources, T. cruzi parasites and gut microbiota. Blood meal analysis revealed feeding on domestic animals (dogs, cats, pigs, goats, and turkeys), synanthropic species (raccoons, opossums, and squirrels), as well as the more sylvatic white-tail deer. Human blood was identified in 11/14 (78%) of bugs, highlighting a frequent vector-human contact. The infection rate with T. cruzi was 53% (8/15), and most infected bugs (6/8) had fed on humans. A total of 41 bacterial families were identified, with significant differences in microbiota alpha and beta diversity between bugs from Louisiana and Illinois. However, predicted metabolic functions remained highly conserved, suggesting important constraints to fulfill their role in bug biology. These results confirmed a significant risk for vector-borne transmission of T. cruzi to humans in Louisiana and Illinois, which warrants more active screening for human infections. Also, while there is broad plasticity in the bacterial composition of T. sanguisuga microbiota, there are strong constraints to preserve metabolic profile and function, making it a good target for novel vector control strategies.
RESUMO
Gyrinicola Yamaguti, 1938, includes 6 species of oxyurid found within the intestinal tract of numerous, larval, anuran species in Europe, Asia, South America, and North America. The systematic placement and hierarchical treatment of the genus has shifted at least 5 times since its discovery; the group was first considered as its own family (Gyrinicolidae), then treated as a subfamily (Gyrinicolinae) of Cosmocercidae, then as a member of the Pharyngodonidae, followed by movement back to the Cosmocercidae, and finally a recent proposal suggested the resurrection of the Gyrinicolidae. Species in the genus vary widely in the morphology of the uterine tract, a characteristic often used to indicate membership in the genus, as it is tied to the reproductive mode. However, until recently very few genetic data were available to aid in the placement of this unique group of worms, and before this study to the best of our knowledge none existed for the North American species. To examine the monophyly and placement of the Gyrinicola we sampled populations of Gyrinicola batrachiensis across North America and screened them for genetic diversity using nuclear markers 18S and 28S. Phylogenies suggest at least 3 clades exist among the nematodes from North America and that these clades, alongside Gyrinicola japonica, form a well-supported group within Oxyuroidea. Further representation of Pharyngodonidae from other vertebrate classes may help clarify the relationship of this historical grouping to other members of the Oxyuroidea.
Assuntos
Nematoides , Oxyuroidea , Animais , Oxyuroidea/anatomia & histologia , Filogenia , Nematoides/genética , Anuros , ReproduçãoRESUMO
Cytauxzoon felis is a tick-transmitted intraerythrocytic apicomplexan infecting felids in the southeastern and midwestern United States. Bobcats (Lynx rufus) are the natural wildlife reservoir of C. felis, where in enzootic areas prevalence can reach 100%. Domestic cats can be subclinically infected with C. felis or can develop cytauxzoonosis. Two studies have documented the presence of C. felis in domestic cats in Illinois; these studies have shown a limited number of cases submitted to specialty labs. During 2014-2018, we obtained blood samples collected by veterinary staff from 514 cats that were apparently healthy and 74 cats that were suspected of cytauxzoonosis. These samples were screened using a sensitive, nested PCR to detect the presence of C. felis DNA. We herein document frequent occurrences of cytauxzoonosis (8-15 cases/year from 4 veterinary clinics) and 12.5% prevalence of subclinical infections in southern Illinois, a locality showing a sharp increase in cases of cytauxzoonosis. Our results suggest a high risk of cytauxzoonosis in southern Illinois, despite only recently being recognized in the area. We found no specific risk factors for cytauxzoonosis or subclinical infections in this location. In addition, cases of cytauxzoonosis occur every month of the year (with the highest frequency in summer) and therefore tick prevention should be used in domestic cats in enzootic regions throughout the year.
Assuntos
Doenças do Gato , Felis , Haemosporida , Lynx , Piroplasmida , Infecções Protozoárias em Animais , Carrapatos , Animais , Gatos , Humanos , Infecções Assintomáticas , Infecções Protozoárias em Animais/epidemiologia , Animais Selvagens , Piroplasmida/genética , Doenças do Gato/epidemiologiaRESUMO
A new species of AlippistrongylusDigiani and Kinsella, 2014, was found in the intestines of the elegant rice rat, Euryoryzomys nitidus, collected in the Amazon rainforest. These mammals were preserved in alcohol and archived in the Colección Científica de Mamíferos del Museo de Historia Natural de la Universidad Mayor de San Marcos and accessed for the observation and investigation for the diversity of their endo-parasites. A total of 857 worms were recovered from the 3 individuals examined. Morphological investigations and comparisons with the only known species of the genus indicate that this is an undescribed species. These nematodes feature the diagnostic characteristic of the genus, being a bifurcated posterior end that consists of a tail and a conical appendage near the level of the vulva and uninterrupted ridges in the synlophe of unequal size. However, the orientation of this conical appendage on the female tail, features of the synlophe, and shape of the copulatory bursa warrant the proposal of an amended diagnosis to include character variability detected in the new species.
Assuntos
Nematoides , Trichostrongyloidea , Animais , Feminino , Peru/epidemiologia , Sigmodontinae/parasitologia , Trichostrongyloidea/anatomia & histologiaRESUMO
Citellinema Hall, 1918 includes 6 valid species of gastrointestinal nematodes of sciurids. Two species occur in the Palearctic and 4 in the Nearctic, 3 of which occur minimally across Colorado, Idaho and Oregon and 1, Citellinema bifurcatum, has a wide distribution across North America. Members of the genus are didelphic, possess a cephalic vesicle, a terminal spine-like process in females and feature robust spicules, consisting of a proximal end fused and semicylindrical shaft connected to a lamina supported by 2 terminal filiform processes. Typically, the size of the spicules is used to differentiate species. As part of the Beringian Coevolution Project, specimens provisionally identified as C. bifurcatum were collected through intensive field sampling of mammals and associated parasites from across localities spanning the Holarctic. These specimens revealed considerable genetic variability at both mitochondrial and nuclear loci, supporting the identification of deeply divergent clades. Examination of these new specimens, along with the holotypes of C. bifurcatum and Citellinema quadrivittati indicates that Citellinema monacis (previously synonymized with C. bifurcatum) should be resurrected and 3 additional species described. We suggest that the apparent bifurcated nature of the spicule should be considered a generic diagnostic trait, while the proportional length of the lamina relative to that of the spicule is used as a specific character. We demonstrate the critical need for continued inventory of often poorly known assemblages of hosts and parasites, contributing to a growing baseline of archival specimens, collections and information that make explorations of faunal structure and diversity possible.
Assuntos
Nematoides , Parasitos , Trichostrongyloidea , Animais , Canadá , Feminino , Marmota , América do Norte , Sciuridae/parasitologiaRESUMO
Originally endemic to South America, the nine-banded armadillo (Dasypus novemcinctus) has recently expanded its range northward to Illinois. With this range expansion comes concern regarding potential incoming pathogens; our research, conducted during 2012-2020, consisted of screening armadillos for the presence of helminths, Trypanosoma cruzi, and Mycobacterium leprae. We screened for the presence of T. cruzi and M. leprae, 2 pathogens known to infect humans, using polymerase chain reaction and enzyme-linked immunosorbent assay, respectively. All 80 samples screened for T. cruzi and all 25 samples screened for M. leprae were negative. No parasite specific to the nine-banded armadillo, such as Aspidodera sogandaresi, was detected. This lack of infection is consistent with the idea that animals may be isolated from their common parasites during periods of range expansion. Lack of infection by T. cruzi in an endemic area suggests that these mammals may not be exposed to the infective stages at this early phase of their colonization. Presently, the armadillo has become established in Illinois, yet they have not introduced their parasites into the area. Our study represents the first effort to document the parasitological record of the expanding armadillo within 30 yr of their initial record in Illinois and the American Midwest. This helminthological record of armadillos in Illinois sets the timeline to observe the establishment of A. sogandaresi in the Midwest.
Assuntos
Tatus/parasitologia , Enteropatias Parasitárias/veterinária , Doenças Parasitárias em Animais/parasitologia , Gastropatias/veterinária , Animais , Illinois/epidemiologia , Enteropatias Parasitárias/epidemiologia , Enteropatias Parasitárias/parasitologia , Doenças Parasitárias em Animais/epidemiologia , Prevalência , Gastropatias/epidemiologia , Gastropatias/parasitologiaRESUMO
The genus Litomosoides Chandler, 1931, includes species that as adults occur in the thoracic and abdominal cavity of mammalian hosts and are presumably vectored by mites. The vertebrate hosts include a variety of Neotropical mammals such as phyllostomid and mormoopid bats; cricetid, sciurid, and hystricognath rodents; and didelphid marsupials. It has been suggested that Litomosoides is not a monophyletic group and that rampant horizontal transfer explains their presence in disparate groups of mammals. Herein we present a phylogenetic reconstruction including mitochondrial genes of 13 vouchered species. This phylogeny is used to reconstruct the evolutionary history of these parasites and the ancestral states of key characters used in species classification, namely, the configuration of the spicules. The historical association of these filarioids with 6 groups of mammals, as well as their ancestral geographic distributions, were reconstructed using Bayesian statistical approaches comparing alternative models of biogeography and evolution and fossil states in selected nodes of the phylogeny. The optimal reconstruction suggests a model of dispersal, extinction, and cladogenesis (DEC) driving the evolution of Litomosoides; the results suggest an origin of Litomosoides in South America and association of ancestors with phyllostomids, and strong evidence of at least 2 host-switching events: 1 of these involving cricetid rodents and the other mormoopid bats. The latter event included a simultaneous geographic expansion of the parasite lineage across South and North America. The host-switching event from phyllostomid bats into cricetid rodents occurred once these rodents diversified across South America; subsequent diversification of the latter clade resulted in 2 branches, each showing expansion of the parasites back into North America. This result suggests that both parasites and cricetid rodents established an association in South America, underwent diversification, and then dispersed into North America. Further, this clade of cricetid-dwelling species includes parasites featuring the "sigmodontis" spicule type. The identification of a single host-switching event involving the disparate lineages of Chiroptera and Rodentia offers a framework to reconstruct the gene evolution and diversification of this lineage after the host-switching event. This will help in predicting the ability of these parasites to infect sympatric mammals.
Assuntos
Arvicolinae/parasitologia , Quirópteros/parasitologia , Filariose/veterinária , Filarioidea/fisiologia , Doenças dos Roedores/parasitologia , Animais , Teorema de Bayes , Filariose/parasitologia , Filariose/transmissão , Filarioidea/anatomia & histologia , Filarioidea/classificação , Genes de Helmintos , Genes Mitocondriais , Marcadores Genéticos , Interações Hospedeiro-Parasita , Funções Verossimilhança , Filogenia , Doenças dos Roedores/transmissãoRESUMO
Cytauxzoon felis is a pathogen responsible for cytauxzoonosis, a highly fatal disease in domestic cats. Although most studies of C. felis have focused on this parasite in domestic cats, bobcats are the reservoir host. In stark contrast, there is little information relative to the progression of C. felis infections in bobcats. We studied bobcats in southern Illinois during 2014-2017 to evaluate which environmental factors (i.e., ambient temperature; number of daylight hours; trapping year, month, and day) influenced C. felis parasitemia levels. Mean ambient temperature at 1 wk and 2 wk prior to sampling was associated with increased parasitemia levels. Vector activity intensifies with higher temperatures, suggesting that increased parasitemia levels are an adaptation to facilitate transmission.
Assuntos
Lynx/parasitologia , Parasitemia/veterinária , Piroplasmida/fisiologia , Infecções Protozoárias em Animais/parasitologia , Animais , Vetores Aracnídeos/parasitologia , Dermacentor/parasitologia , Reservatórios de Doenças/parasitologia , Reservatórios de Doenças/veterinária , Eritrócitos/parasitologia , Modelos Lineares , Meio-Oeste dos Estados Unidos/epidemiologia , Parasitemia/epidemiologia , Parasitemia/parasitologia , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/transmissão , Estações do AnoRESUMO
The Gulf Coast tick, Amblyomma maculatum, is of public and veterinary health concern, as it is the primary vector of Rickettsia parkeri and Hepatozoon americanum, causative agents of Rickettsiosis and American canine hepatozoonosis. The Gulf Coast tick's range has expanded over the last 50 yr into the mid-Atlantic states, and its expansion is expected to continue northward. We are reporting the presence of A. maculatum for the first time in Illinois, including a total of 18 specimens collected at 6 different sites during surveys in 2013 and 2019. Fourteen of these specimens were screened for Rickettsia parkeri, which resulted in the detection of this bacteria in 8 samples from 4 counties. By depositing these specimens in scientific collections, we provide materialistic evidence of their establishment in 2 counties. We urge health officials to rely on and use scientific collections to document the expansion of these and other vectors across the country. Additionally, we recommend that health practitioners become aware of the clinical similarities between Rocky Mountain Spotted Fever (caused by Rickettsia rickettsii) and "tidewater" fever (caused by R. parkeri).
Assuntos
Vetores Aracnídeos/fisiologia , Ixodidae/fisiologia , Infecções por Rickettsia/transmissão , Rickettsia/fisiologia , Animais , Vetores Aracnídeos/anatomia & histologia , Vetores Aracnídeos/microbiologia , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/isolamento & purificação , DNA Bacteriano/análise , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , Feminino , Illinois , Ixodidae/anatomia & histologia , Ixodidae/microbiologia , Masculino , Reação em Cadeia da Polimerase em Tempo Real , Rickettsia/genética , Rickettsia/isolamento & purificação , Infecções por Rickettsia/microbiologiaRESUMO
Tlacuatzoxyuris simpsoni n. gen. n. sp. is described from the cecum of the gray opossum, Tlacuatzin canescens, a species endemic to the deciduous dry forest of Mexico. The digestive tracts of four specimens were examined for parasites; three of these were archived in the American Museum of Natural History and one was a live capture. Relative to the other four monotypic genera of pinworms known to infect opossums, the new genus is diagnosed on the basis of a round cephalic plate with a semicircular stoma surrounded by a rim. In addition, males feature a prominent cephalic vesicle not fully developed in females, accounting for sexual dimorphism. The new species includes small worms that feature a conspicuous, not reticulated cephalic vesicle and semicircular stoma and lateral alae with two crests. In addition, the postcloacal cuticle of males features a small area with ornamentation between cloaca and submedial papillae. Finally, both spicule and gubernaculum are relatively short. Although the eggs of Tlacuatzoxyuris n. gen. are unknown, the conspicuous differences in traits used in the diagnosis of genera prompted us to propose a new genus for the new species. This is the first species of Oxyuridae reported in mouse opossums outside South America, and the fifth species of the family occurring in didelphimorph marsupials. This is an example of the usefulness of documenting the diversity of parasites associated with this unique clade of mammals through the examination of preserved tissues.
Assuntos
Enterobíase/veterinária , Enterobius/classificação , Enterobius/isolamento & purificação , Gambás/parasitologia , Animais , Ceco/parasitologia , Enterobius/anatomia & histologia , Feminino , MasculinoRESUMO
Museum specimens play an increasingly important role in predicting the outcomes and revealing the consequences of anthropogenically driven disruption of the biosphere. As ecological communities respond to ongoing environmental change, host-parasite interactions are also altered. This shifting landscape of host-parasite associations creates opportunities for colonization of different hosts and emergence of new pathogens, with implications for wildlife conservation and management, public health, and other societal concerns. Integrated archives that document and preserve mammal specimens along with their communities of associated parasites and ancillary data provide a powerful resource for investigating, anticipating, and mitigating the epidemiological, ecological, and evolutionary impacts of environmental perturbation. Mammalogists who collect and archive mammal specimens have a unique opportunity to expand the scope and impact of their field work by collecting the parasites that are associated with their study organisms. We encourage mammalogists to embrace an integrated and holistic sampling paradigm and advocate for this to become standard practice for museum-based collecting. To this end, we provide a detailed, field-tested protocol to give mammalogists the tools to collect and preserve host and parasite materials that are of high quality and suitable for a range of potential downstream analyses (e.g., genetic, morphological). Finally, we also encourage increased global cooperation across taxonomic disciplines to build an integrated series of baselines and snapshots of the changing biosphere. Los especímenes de museo desempeñan un papel cada vez más importante tanto en la descripción de los resultados de la alteración antropogénica de la biosfera como en la predicción de sus consecuencias. Dado que las comunidades ecológicas responden al cambio ambiental, también se alteran las interacciones hospedador-parásito. Este panorama cambiante de asociaciones hospedador-parásito crea oportunidades para la colonización de diferentes hospedadores y para la aparición de nuevos patógenos, con implicancias en la conservación y manejo de la vida silvestre, la salud pública y otras preocupaciones de importancia para la sociedad. Archivos integrados que documentan y preservan especímenes de mamíferos junto con sus comunidades de parásitos y datos asociados, proporcionan un fuerte recurso para investigar, anticipar y mitigar los impactos epidemiológicos, ecológicos y evolutivos de las perturbaciones ambientales. Los mastozoólogos que recolectan y archivan muestras de mamíferos, tienen una oportunidad única de ampliar el alcance e impacto de su trabajo de campo mediante la recolección de los parásitos que están asociados con los organismos que estudian. Alentamos a los mastozoólogos a adoptar un paradigma de muestreo integrado y holístico y abogamos para que esto se convierta en una práctica estándarizada de la obtención de muestras para museos. Con este objetivo, proporcionamos un protocolo detallado y probado en el campo para brindar a los mastozoólogos las herramientas para recolectar y preservar materiales de parásitos y hospedadores de alta calidad y adecuados para una gran variedad de análisis subsecuentes (e.g., genéticos, morfológicos, etc.). Finalmente, también abogamos por una mayor cooperación global entre las diversas disciplinas taxonómicas para construir una serie integrada de líneas de base y registros actuales de nuestra cambiante biosfera.
RESUMO
Cytauxzoon felis, and the resulting disease, cytauxzoonosis, is an emerging threat to domestic cats in the Midwest and Southeastern United States. Domestic cats that survive cytauxzoonosis (or are subclinically infected) are chronically infected with C. felis, yet to date, there is no information relative to chronic infections in bobcats, the natural reservoir. Over a period of 3.5 years (2014-2017), we captured and re-captured 5 bobcats in southern Illinois. One bobcat was captured each year of trapping, 1 was caught in the first and third year and 3 were recaptured approximately 1 year apart. We screened bobcats for the presence of C. felis using a nested PCR that amplified the nuclear small subunit (SSU) 18S rRNA. In addition, we amplified and sequenced the internal transcribed spacers 1 and 2 (ITS1 and ITS2) to detect if the strains of C. felis in each bobcat were consistent over time. All bobcats were positive for C. felis at the initial and subsequent capture(s). Bobcats that were PCR-positive for C. felis had blood smears screened for the presence of C. felis; all PCR-positive bobcats had detectable parasites in blood smears. The strains of C. felis present were consistent each year in 4 of 5 bobcats indicating these bobcats remained infected during this period. One bobcat appeared to be infected with a different strain based on a polymorphism at a nucleotide in ITS1. Our study provides important details of the epizootiology of C. felis: bobcats are chronically infected and are not immune to reinfection with new strains of C. felis.
Assuntos
Animais Selvagens/parasitologia , Doenças do Gato/epidemiologia , Lynx/parasitologia , Piroplasmida/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Animais , Animais Domésticos , Doenças do Gato/parasitologia , Gatos/parasitologia , DNA de Protozoário/genética , DNA Espaçador Ribossômico/genética , Meio-Oeste dos Estados Unidos/epidemiologia , Piroplasmida/genética , Reação em Cadeia da Polimerase , Infecções Protozoárias em Animais/epidemiologia , Infecções Protozoárias em Animais/transmissão , RNA Ribossômico 18S/genética , Sudeste dos Estados Unidos/epidemiologiaRESUMO
Cytauxzoon felis is an intraerythrocytic apicomplexan of felids enzootic in the southeastern United States. In domestic cats (Felis catus), this parasite can result in the highly fatal disease cytauxzoonosis or bobcat fever. Bobcats (Lynx rufus) are the wild animal reservoir host. To date, the characterization of prevalence of C. felis in bobcats is mostly based on broad-scale surveys from hunter-harvested specimens collected across large geographic areas, usually consisting of multiple states. Detailed studies on the development, transmission, distribution, effects, and prevalence of C. felis in the tick vectors are scarce. To fill some of these gaps in the literature, such as prevalence in ticks and bobcats in a discrete region, we examined bobcats and ticks in an 8,000-km2 portion of southern Illinois. We screened for C. felis using a nested polymerase chain reaction that amplifies a fragment of the nuclear small subunit (SSU) 18S rRNA. We screened 125 individual bobcats collected in southern Illinois from 2003 to 2015; of these, 70.6% were positive for C. felis. In addition, we screened 214 ticks of both vector species (Amblyomma americanum and Dermacentor variabilis) and detected C. felis in 15.6% of them; this prevalence is higher than reported by previous surveys. Our study reports the prevalence of C. felis in ticks and bobcats from south Illinois. We found that 70.6% of bobcats and 15.6% of ticks were infected with C. felis, which suggests risk of transmission to domestic cats.
Assuntos
Vetores Aracnídeos/parasitologia , Lynx/parasitologia , Piroplasmida/isolamento & purificação , Infecções Protozoárias em Animais/epidemiologia , Carrapatos/parasitologia , Animais , DNA de Protozoário/isolamento & purificação , Reservatórios de Doenças , Feminino , Illinois/epidemiologia , Modelos Lineares , Masculino , Prevalência , Infecções Protozoárias em Animais/parasitologia , Infecções Protozoárias em Animais/transmissão , Estações do AnoRESUMO
Based on the number and arrangement of cuticular ridges and configuration of the dorsal ray, nematode specimens collected from the small intestine of eight Guianan arboreal mice, Oecomys auyantepui (Rodentia: Sigmodontinae), in French Guiana are herein described and characterized. Guerrerostrongylus marginalis n. sp. (Heligmosomoidea: Heligmonellidae) shows a synlophe consisting of more than 40 ridges and a unique bursal arrangement with ray 8 (externo-dorsal) extending to the edge of the bursal margin, and appearing more prominent than the dorsal ray. This bursal arrangement is common in members of Hassalstrongylus Durette-Desset, 1971, but uncommon in the other four species in Guerrerostrongylus Sutton & Durette-Desset, 1991. The placement of the new species in Guerrerostrongylus is based on the number and nature of cuticular ridges and the ray arrangement and symmetry of the caudal bursa. Diagnostic characteristics of Guerrerostrongylus marginalis n. sp. include the length of ray 8 relative to bursal margin, the relative size of the spicules and vestibule, and the number of eggs in the uterus. We propose an amendment to the generic diagnosis of Guerrerostrongylus to modify the characters of the long rays 6 (postero-lateral), rays 8 (externo-dorsal), and dorsal ray as diagnostic, since at least ray 6 appears to be short in two different species in the genus, namely G. ulysi Digiani, Notarnicola & Navone, 2012 and G. marginalis n. sp.
Assuntos
Enteropatias Parasitárias/veterinária , Doenças dos Roedores/parasitologia , Sigmodontinae/parasitologia , Trichostrongyloidea/isolamento & purificação , Tricostrongiloidíase/veterinária , Animais , DNA de Helmintos/genética , Feminino , Florestas , Guiana Francesa , Enteropatias Parasitárias/parasitologia , Intestino Delgado/parasitologia , Masculino , Especificidade da Espécie , Trichostrongyloidea/anatomia & histologia , Trichostrongyloidea/classificação , Trichostrongyloidea/genética , Tricostrongiloidíase/parasitologiaRESUMO
The trichostrongylid nematode Travassostrongylus scheibelorum sp. n. from the Linnaeus' mouse opossum, Marmosa murina (Linnaeus) (type host), and the woolly mouse opossum, Marmosa demerarae (Thomas), from French Guiana is described. The nematodes have a synlophe with ridges frontally oriented from right to left, six dorsal and six ventral, at midbody; seven dorsal and seven ventral posterior to the vulva, and two cuticular thickenings within the lateral spaces; a long dorsal ray and a pointed cuticular flap covering the vulva. This is the 12th species of Travassostrongylus Orloff, 1933, which includes species featuring ridges around the synlophe and a didelphic condition. These traits contrast with those in other genera in the Viannaiidae Neveu-Lemaire, 1934, which feature ventral ridges on the synlophe of adults and a monodelphic condition. Members of the family are chiefly Neotropical and are diagnosed based on the presence of a bursa of the type 2-2-1, 2-1-2 or irregular, and cuticle without ridges on the dorsal side (at least during one stage of their development). Herein, we present a reconstruction of the ancestral states of the didelphic/monodelphic condition and the cuticular ridges that form the synlophe in opossum-dwelling trichostrongyles, namely Travassostrongylus and Viannaia Travassos, 1914. Our investigations suggest they are not reciprocal sister taxa and that the change from didelphy to monodelphy and the loss of dorsal ridges, occurred in the common ancestor of species of Viannaia. These results suggest a synlophe with three ventral ridges is not plesiomorphic in the opossum dwelling trichostrongylids.
Assuntos
Nematoides/anatomia & histologia , Nematoides/classificação , Infecções por Nematoides/veterinária , Gambás , Animais , Feminino , Guiana Francesa/epidemiologia , Masculino , Nematoides/genética , Infecções por Nematoides/epidemiologia , Infecções por Nematoides/parasitologia , Filogenia , Especificidade da EspécieRESUMO
Macuahuitloides inexpectans n. gen., n. sp. (Molineidae: Anoplostrongylinae) is herein described. The description is based on specimens removed from the small intestine of ghost-faced bats, Mormoops megalophylla, from central Mexico. The monotypic genus is unique in featuring sexual dimorphism on the cuticular ornamentation, which consists of the presence of spines on the anterior quarter of females, and of the presence of rugosities on the surface of the cephalic vesicle of males. The cuticular spines are arranged in spiral rings on the anterior quarter of the body, and there is no trace of said structures on the cuticle of males. The synlophe of the males possess 12 ridges, whereas there is no synlophe in females. Finally, females show a prominent caudal terminus (spine) and 3 subterminal tubercles, whereas males show bursal rays in a 3-2 arrangement, with a relatively prominent dorsal ray.