Molecular diversity and polyparasitism of avian trypanosomes in the Brazilian Atlantic Rainforest.

The current study proposes to investigate the diversity and phylogeny of trypanosomes parasitizing wild birds from the Brazilian Atlantic Forest. Cytological examination was carried out by light microscopy of blood smears and positive birds were selected for amplification of the 18S rDNA sequence through PCR. The resulting amplicons were subjected to purification, cloning, and sequencing analysis. Phylogenetic reconstruction was conducted, including all avian trypanosomes representative's lineages. A total of ten bird samples from species of Turdus flavipes (N=1/12), T. albicollis (N=1/8), Tachyphonus coronatus (N=6/121), Thamnophilus caerulescens (N=1/22) and Synallaxis spixi (N=1/8) were positive for Trypanosoma spp. In the six specimens of T. coronatus, five distinct lineages of Trypanosoma spp. 18S-rRNA were observed in ninety sequences obtained, and using the strategy of cloning independent PCR, it was possible to observe that two of them were related to T. avium (JB01/JB02), and three were closed related to T. bennetti (JB03/ JB04/JB05). Addionaly, all fifteen sequences obtained from T. caerulescens/ S. spixi/T. flavipes/T. albicollis were identical. The present research is the first study to access molecular diversity and polyparasitism by avian trypanosomes in Brazil. The current research exhibits the wide genetic variability in avian trypanosomes and its non-specific relationship with its avian hosts.

New Finds on the Systematics of Cycloposthiid Ciliates (Ciliophora: Entodiniomorphida: Cycloposthiidae) Based on New 18S-rDNA Sequences from a Brazilian Capybara.

The family Cycloposthiidae (Entodiniomorphida) comprises ciliated protists that are symbionts of the gastrointestinal tract of several herbivore mammals, such as rodents, elephants, equids, primates, hippopotamus, marsupials, rhinoceros and tapir, where they contribute to the digestion of their host's plant-based diet. Despite the significance of these ciliates to the evolution of their hosts, many characters used in the taxonomy of the group are homoplastic and most of the valid species do not have molecular data available. For these reasons the systematics of this family is poorly understood. Here, we sequenced the 18S-rDNA of ten cycloposthiids, including nine Cycloposthium spp. and Monoposthium cynodontum, all of them isolated from the cecum of a Brazilian capybara. Our phylogenetic analyses indicate that the family Cycloposthiidae might be polyphyletic, while M. cynodontum and Cycloposthium spp. constitute a single monophyletic group. Given the great morphological and molecular similarities between members of M. cynodontum and Cycloposthium ciliates, it is possible that this species, although it has been described in the genus Monoposthium, is actually a Cycloposthium ciliate.

Molecular and Morphological Characterization of a Brazilian Lineage of Plasmodium ( Novyella) Unalis in Turdus Spp. (Passeriformes) of the Atlantic Forest, with Remarks on New Hosts and High Genetic Variation.

Plasmodium spp. are haemosporidian protozoans that alternate their live cycles between bloodsucking Culicidae dipterans and vertebrate hosts (mammals, reptiles, and birds). In birds, these parasites are the causative agents of the so-called avian malaria, a disease associated with considerable declines and extinctions in the avifauna in different geographical regions. In this work, we applied a multidisciplinary approach, light microscopy and cytochrome oxidase b (cyt b) gene sequence analysis, for characterization of Plasmodium spp. found in association with wild birds of the genus Turdus, collected in Atlantic forest fragments of southeastern Brazil. From the total 90 analyzed birds, 58 (47 Turdus rufiventris, 9 Turdus leucomelas, 1 Turdus albicollis, and 1 Turdus flavipes) were positively infected with Plasmodium unalis, a haemosporidian that was previously detected in Turdus fuscater in Colombia and in penguins in Brazil, but has never been found in association with these Turdus species of this present work. Moreover, all 7 new sequences of P. unalis cyt b gene clustered into a monophyletic clade with previously characterized P. unalis sequences with a mean genetic divergence of 1.6% and with a maximum divergence of 3.1%, indicating for a high degree of intraspecific polymorphism within this parasitic species. Together, our data highlight the existence a high degree of intraspecific variation within P. unalis and highlight the importance of integrative taxonomy to an accurate identification and characterization of avian haemosporidian parasites.

A House for Two--Double Bacterial Infection in Euplotes woodruffi Sq1 (Ciliophora, Euplotia) Sampled in Southeastern Brazil.

Several ciliated protists form symbiotic associations with a diversity of microorganisms, leading to drastic impact on their ecology and evolution. In this work, two Euplotes spp. sampled in Rio de Janeiro, Brazil, were identified based on morphological and molecular features as Euplotes woodruffi strain Sq1 and E. encysticus strain Sq2 and investigated for the presence of endosymbionts. While E. woodruffi Sq1 stably hosts two bacterial populations, namely Polynucleobacter necessarius (Betaproteobacteria) and a new member of the family "Candidatus Midichloriaceae" (Alphaproteobacteria, Rickettsiales), here described as "Candidatus Bandiella woodruffii," branching with a broad host range bacterial group found in association with cnidarians, sponges, euglenoids, and some arthropods; in E. encysticus Sq2 no symbiotic bacterium could be detected. The dispersion ability of this novel bacterium was tested by co-incubating E. woodruffi Sq1 with three different ciliate species. Among the tested strains "Ca. B. woodruffii" could only be detected in association with E. encysticus Sq2 with a prevalence of 20 % after 1 week and 40 % after 2 weeks, maintaining this level for up to 6 months. Nevertheless, this apparent in vitro association was abolished when E. woodruffi Sq1 donor was removed from the microcosm, suggesting that this bacterium has the capacity for at least a short-term survival outside its natural host and the aptitude to ephemerally interact with other organisms. Together, these findings strongly suggest the need for more detailed investigations to evaluate the host range for "Ca. B. woodruffii" and any possible pathogenic effect of this bacterium on other organisms including humans.

Redescription and Phylogenetic Position of Condylostoma arenarium Spiegel, 1926 (Ciliophora, Heterotrichea) from Guanabara Bay, Brazil.

Details on Condylostoma arenarium infraciliature have not been described; therefore, it is considered a poorly known species. The lack of detailed description on C. arenarium morphology caused several misidentifications that have accumulated in the literature. In this study, we present the first complete description of C. arenarium infraciliature based on protargol-impregnated organisms and scanning electron microscopy. We also have inferred the phylogenetic position of this species based on 18S rRNA sequences. The main characteristics of C. arenarium population from Guanabara Bay are as follows: in vivo elongated body shape with 350-600 µm length × 70-220 µm width, they are highly contractile when subjected to disturbances, green-yellowish cortical granules are present, contractile vacuoles absent, V-shaped peristome comprises approximately 1/5 of the total length, adoral zone with 83-145 membranelles, 1-2 small frontal cirrus observed only in impregnated specimens, 10-15 fiber-like stripes arranged transversely on the inner wall of the oral cavity, 30-45 somatic kineties, moniliform macronucleus with 15-20 nodules. Some observations on morphogenesis of C. arenarium were also included. In phylogenetic analyses, C. arenarium clustered with Condylostoma sp. within a clade composed of three C. curva sequences with high support values.