Pseudascarophis brasiliensis sp. nov. (Nematoda: Cystidicolidae)

A new species of Pseudascarophis Nematoda: Cystidicolidae) found in the stomach of Kyphosus sectatrix (Linnaeus) (Kyphosidae), off Rio de Janeiro, Brazil, is described. The new species can be differentiated from the other congeners by the presence of lateral alae, distinct but inconspicuous cephalic papillae at the anterior end, three pairs of precloacal and one pair of adcloacal papillae in males, egg morphology and morphometry of glandular oesophagus and spicules. Pseudascarophis tropica is transferred to Ascarophis as Ascarophis tropica (Solov?eva) comb. n. due to its ambiguous diagnosis.Fil: Pereira, Felipe Bisaggio. Universidade Federal Rural do Río de Janeiro. Departamento de Parasitologia Animal. Curso de Pós-Graduação em Ciências Veterinárias; Brasi;Fil: Pereira, Aldenice de Nazaré. Universidade Federal Rural do Río de Janeiro. Departamento de Parasitologia Animal. Curso de Pós-Graduação em Ciências Veterinárias; Brasi;Fil: Timi, Juan Tomas. Universidad Nacional de Mar del Plata. Facultad de Cs.exactas y Naturales. Departamento de Biologia. Laboratorio de Parasitologia; Argentina; Consejo Nacional de Invest.cientif.y Tecnicas. Centro Cientifico Tecnol.conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras; Argentina;Fil: Luque, José Luis. Universidade Federal Rural do Río de Janeiro. Departamento de Parasitologia Animal. Curso de Pós-Graduação em Ciências Veterinárias; Brasi

Estrutura da comunidade de helmintos associados ao lagarto Tropidurus torquatus (Squamata: Tropiduridae) em uma área de afloramento rochoso no distrito de Toledos, Juiz de Fora, MG

The helminth community of the lizard Tropidurus torquatus from a rocky outcrop located in Minas Gerais state, southeast Brazil, was studied. Ninety two of the one hundred ten individuals examined (83,6%) harbored helminths. A total of five helminth species were found, tree nematodes: Physaloptera lutzi, Parapharyngodon sp. and Oswaldofilaria sp., one cestode species and one acanthocaphalan cystacanth not identified. Only nematode species had sufficient data to perform ecological analysis with Physaloptera lutzi showing the highest prevalence (67,3%) and mean intensity (4,86±4,85). Prevalence and intensity of infection between males and females hosts differed only for Oswaldofilaria sp., with males showing the highest values. Total and P. lutzi intensity of infection were different among males and females hosts, with males showing the highest values. The host body size was positively related to intensity of infection for all nematode species. Local seasonality had no influence in the helminth community structure. Host diet, sexual dimorphism and behavior (territorialism, forage strategy) represented important factors in the structuring of this parasite community. In general lines, the helminth community was species poor and non interactive, representing a typical community structure found in herps hosts.A comunidade parasitária do lagarto Tropidurus torquatus em uma área de campo rupestre localizada no estado de Minas Gerais, sudeste do Brasil, foi estudada. Dos 110 hospedeiros analisados, 92 (83,6%) estavam infectados. Foram encontradas cinco espécies de helmintos, três de nematóide: Physaloptera lutzi, Parapharyngodon sp. e Oswaldofilaria sp., uma espécie de cestóide e um cistacanto não identificados. Apenas as espécies de nematóides apresentaram dados suficientes para analises ecológicas, sendo P. lutzi a espécie mais prevalente (67,3%) e com maior intensidade parasitária (4,86±4,85). Somente para Oswaldofilaria sp. foram encontradas diferenças significativas na prevalência e intensidade parasitária entre hospedeiros fêmeas e machos, esses últimos apresentando os maiores valores. A intensidade parasitária total e de P. lutzi também diferiram entre os sexos de hospedeiros com machos apresentando os maiores valores. O tamanho corporal do hospedeiro correlacionou-se de forma positiva com a intensidade de infecção de todas as espécies de nematóides. A sazonalidade local não influenciou de forma significativa a estrutura da comunidade componente de parasitos estudada. Aspectos do hospedeiro como dieta, dimorfismo sexual e comportamento (territorialiasmo e forrageamento) representaram importantes fatores na determinação da estrutura dessa comunidade de helmintos. De maneira geral, a comunidade parasitária apresentou baixa riqueza de espécies e um caráter não interativo, características comuns em comunidades parasitárias de répteis como hospedeiros.CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológic

Pseudascarophis brasiliensis sp. nov. (Nematoda: Cystidicolidae) parasitic in the Bermuda chub Kyphosus sectatrix (Perciformes: Kyphosidae) from southeastern Brazil

A new species of Pseudascarophis (Nematoda: Cystidicolidae) found in the stomach of Kyphosus sectatrix (Linnaeus) (Kyphosidae), off Rio de Janeiro, Brazil, is described. The new species can be differentiated from the other congeners by the presence of lateral alae, distinct but inconspicuous cephalic papillae at the anterior end, three pairs of precloacal and one pair of adcloacal papillae in males, egg morphology and morphometry of glandular oesophagus and spicules. Pseudascarophis tropica is transferred to Ascarophis as Ascarophis tropica (Solov'eva) comb. n. due to its ambiguous diagnosis

On the Evolutionary History of Philometridae (Nematoda: Dracunculoidea): Integrative Taxonomy Reveals Evidence of Character Diversification and Host–Parasite Cophylogenetic Patterns

(1) Background: Integrative taxonomy has been important in the comprehension of relationships among nematode parasites. Philometridae is a highly diverse family of these organisms, but poorly-known regarding genetic characterization and evolution. An integrative taxonomic analysis was performed to improve the knowledge of the evolutionary history of Philometridae. (2) Methods: Phylogenies were reconstructed based on genetic sequences alone and integrated with morphological/life history traits, which were phylogenetically mapped. The host–parasite cophylogeny was evaluated. (3) Results: Previously unpublished 28S rDNA sequences are given for some species. The phylogeny from this marker, although limited by data scarcity, showed similar patterns as that from 18S rDNA. Clades shared common features related to the structure of the esophagus and of the tail in males (especially the gubernaculum), site of infection, habitat, host taxa and geographic origin; most of these features were phylogenetically informative. The integrative phylogeny was better resolved. A cophylogenetic signal was present mainly in clades of freshwater species. (4) Conclusions: The speciation process in Philometridae is not unique or uniform; host capture, host–parasite co-evolution and allopatric (especially in freshwater) events may be occurring simultaneously in different lineages, places and times. Cases of plesiomorphy retention probably occur. Evolutionary convergence of poorly-informative characters is suggested, even though they are important for species diagnosis

Integrative approach on Pharyngodonidae (Nematoda: Oxyuroidea) parasitic in reptiles: Relationship among its genera, importance of their diagnostic features, and new data on <i>Parapharyngodon bainae</i>

<div><p>The first integrative approach using sequences of two genes (18S and 28S rRNA) plus morphological and life history traits, was explored in Pharyngodonidae nematodes parasitic in reptiles. Additionally, first genetic characterization of <i>Parapharyngodon bainae</i> and new data on its morphology are given. This approach evaluated the phylogenetic relationships among genera within Pharyngodonidae, as well as the importance of their diagnostic morphological features. Specimens of <i>P</i>. <i>bainae</i> were collected from faecal pellets of the lizard <i>Tropidurus torquatus</i> in the State of Minas Gerais, Brazil. Nematodes were fixed for scanning electron microscopy and molecular procedures. Morphological observations revealed the accurate structures of cephalic end, of cloacal region in males, of vulva and eggs. Phylogenetic reconstructions were based upon four datasets: aligned sequences of the 18S, of the 28S, of both concatenated genes and of combined morphological and molecular datasets. Bayesian inference and maximum likelihood were performed to infer the phylogenies of molecular datasets and maximum parsimony to infer that of all-combined data. Pharyngodonid parasites of reptiles seem to configure two general monophyletic lineages, as previously assertions. Results also showed the monophyly of <i>Spauligodon</i>, <i>Skrjabinodon</i> and <i>Parapharyngodon</i>, as well as the clear separation between the latter and <i>Thelandros</i>. Combination of datasets improved nodal supports. Analysis of the all-combined datasets revealed the importance of vulval position and egg morphology as phylogenetic informative traits. However, characters of male caudal morphology appear as are highly homoplastic, and seem to be product of convergent evolution or multiple losses of ancestral traits. The closely-related <i>Thelandros</i> and <i>Parapharyngodon</i> are kept valid and their diagnosis should be based upon the position of the operculum in eggs (terminal or subterminal, respectively). Some inconsistencies in the scarce molecular and morphological databases were noted. Thus, new genetic data is required for further conclusions and current database must be evaluated with attention.</p></div

Life history and morphological characters and states^a associated with the taxa used in the all-data integrated analysis.

<p>Life history and morphological characters and states<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0200494#t002fn001" target="_blank">^a</a> associated with the taxa used in the all-data integrated analysis.</p

Characters (morphological and life history) that were mapped in the maximum parsimony tree associated with states, no. of steps and consistency index (CI).

<p>Characters (morphological and life history) that were mapped in the maximum parsimony tree associated with states, no. of steps and consistency index (CI).</p

Scanning electron micrographs of <i>Parapharyngodon bainae</i> collected from faecal pellets of <i>Tropidurus torquatus</i>.

<p>A, B, Cephalic end of female and male, respectively, apical views (asterisks indicate lamellar projections). C, Detail of amphidial pore in lateral labium. D, E, Tail of female, ventral and lateral views, respectively. F, Egg. G, Vulva, apical view. H, I, Tail and cloacal region of male, respectively, ventral views (arrowhead indicates spicule tip). Abbreviations: a, amphid; o, operculum; p, phasmid.</p

Phylogenetic relationships among pharyngodonid nematodes parasitic in reptiles.

<p>(A) Tree generated using Bayesian inference of the concatenated sequences of 18S and 28S rDNA; full and empty circles indicate nodal support > 0.96 and > 0.80, respectively, for Bayesian posterior probability (4 × 10⁶ generations, sampling frequency = 4 × 10³, burn-in = 1 × 10⁶) and > 96 and > 80, respectively, for maximum likelihood bootstrap (1000 replications). (B) Tree generated using maximum parsimony of the combined data from morphological-life history and molecular datasets (2423 characters, 274 parsimony informative, CI 0.786); full and empty circles indicate bootstrap support > 96 and > 80, respectively (2,000 replications); life history and morphological traits are mapped and labelled in details. Specimen in bold is from the present study.</p