Arthropod-borne agents in wild Orinoco geese (Neochen jubata) in Brazil

Novel Tick-Borne Anaplasmataceae Genotypes in Tropical Birds from the Brazilian Pantanal Wetland

Despite numerous reports of Anaplasmataceae agents in mammals worldwide, few studies have investigated their occurrence in birds. The present study aimed to investigate the occurrence and molecular identity of Anaplasmataceae agents in birds from the Pantanal wetland, Brazil. Blood samples were collected from 93 different species. After DNA extraction, samples positive for the avian β-actin gene were subjected to both a multiplex quantitative real-time (q)PCR for Anaplasma and Ehrlichia targeting the groEL gene and to a conventional PCR for Anaplasmataceae agents targeting the 16S rRNA gene. As a result, 37 (7.4%) birds were positive for Anaplasma spp. and 4 (0.8%) for Ehrlichia spp. in the qPCR assay; additionally, 13 (2.6%) were positive for Anaplasmataceae agents in the PCR targeting the 16S rRNA gene. The Ehrlichia 16S rRNA sequences detected in Arundinicola leucocephala, Ramphocelus carbo, and Elaenia albiceps were positioned closely to Ehrlichia sp. Magellanica. Ehrlichia dsb sequences detected in Agelasticus cyanopus and Basileuterus flaveolus grouped with Ehrlichia minasensis. The 16S rRNA genotypes detected in Crax fasciolata, Pitangus sulphuratus and Furnarius leucopus grouped with Candidatus Allocryptoplasma. The 23S-5S genotypes detected in C. fasciolata, Basileuterus flaveolus, and Saltator coerulescens were related to Anaplasma phagocytophilum. In conclusion, novel genotypes of Anaplasma, Ehrlichia, and Candidatus Allocryptoplasma were detected in birds from the Pantanal wetland.

Anaplasmataceae presence in Amblyomma calcaratum associated with anteaters (Tamandua tetradactyla) in the rainforest ecoregion, Argentina

Bacteria of the sister genera Ehrlichia and Anaplasma (Anaplasmataceae) are obligate intracellular Alphaproteobacteria that are transmitted mostly through arthropod vectors. These agents can infect different vertebrate cells, depending on the species involved, and can cause diseases in animals and humans. In this study, we evaluated the presence of Anaplasmataceae bacteria in Amblyomma calcaratum ticks collected from a road-killed Tamandua tetradactyla in the Rainforest ecoregion in Argentina. All samples were screened for Anaplasmataceae DNA using a real-time PCR assay targeting the 16S rRNA gene. Evidence of Anaplasmataceae DNA was detected in three out of thirty-nine Am. calcaratum ticks. Phylogenetic analysis of a portion of 16S rRNA gene positioned one sample (Ehrlichia sp. strain Ac124) with Ehrlichia sequences and the other two samples with Anaplasma sequences; Anaplasma sp. strain Ac145 close to Anaplasma odocoilei and Anaplasma sp. strain Ac152 in an ancestral position to most Anaplasma species. The groEL sequence obtained showed that Ehrlichia sp. strain Ac124 was phylogenetically related to Ehrlichia sp. strain Iberá reported infecting Amblyomma tigrinum from Iberá wetlands in Argentina. Phylogenetic analysis using the rpoB sequence positioned Anaplasma sp. strain Ac145 close to the canine pathogen Anaplasma platys, while Anaplasma sp. strain Ac152 was positioned close to the bovine pathogen Anaplasma marginale. In this study, three Anaplasmataceae agents were detected in adults of Am. calcaratum associated with a T. tetradactyla. These results suggest that the number of Anaplasmataceae species, as well as their distribution, is largely unknown.

Molecular detection of blood-borne agents in vampire bats from Brazil, with the first molecular evidence of Neorickettsia sp. in Desmodus rotundus and Diphylla ecaudata

Bats (Mammalia, Chiroptera) represent the second largest group of mammals. Due to their ability to fly and adapt and colonize different niches, bats act as reservoirs of several potentially zoonotic pathogens. In this context, the present work aimed to investigate, using molecular techniques, the occurrence of blood-borne agents (Anaplasmataceae, Coxiella burnetii, hemoplasmas, hemosporidians and piroplasmids) in 198 vampire bats sampled in different regions of Brazil and belonging to the species Desmodus rotundus (n=159), Diphylla ecaudata (n=31) and Diaemus youngii (n=8). All vampire bats liver samples were negative in PCR assays for Ehrlichia spp., Anaplasma spp., piroplasmids, hemosporidians and Coxiella burnetii. However, Neorickettsia sp. was detected in liver samples of 1.51% (3/198) through nested PCR based on the 16S rRNA gene in D. rotundus and D. ecaudata. This is the first study to report Neorickettsia sp. in vampire bats. Hemoplasmas were detected in 6.06% (12/198) of the liver samples using a PCR based on the 16S rRNA gene. The two 16S rRNA sequences obtained from hemoplasmas were closely related to sequences previously identified in vampire and non-hematophagous bats from Belize, Peru and Brazil. The genotypic analysis identified a high diversity of bat-associated hemoplasma genotypes from different regions of the world, emphasizing the need for studies on this subject, in order to better understand the mechanisms of co-evolution between this group of bacteria and their vertebrate hosts. The role of neotropical bat-associated Neorickettsia sp. and bats from Brazilian in the biological cycle of such agent warrant further investigation.

Haemosporidian parasites in the ash-breasted Sierra finch (Geospizopsis plebejus): insights from an Andean dry forest population

Haemosporidian genera Plasmodium, Haemoproteus and Leucocytozoon, responsible for avian malarial infections, are highly diverse and have a wide range of health effects and predictors, depending on the host and its environmental context. Here, we present, for the first time, detailed information on the identity, prevalence and parasitaemia of haemosporidians and other haemoparasites that infect the ash-breasted Sierra finch, Geospizopsis plebejus, in an Andean dry forest. We study the consequences of infection in the host body and health conditions and explore the environmental and intrinsic factors that influence infection status and parasitaemia. We conducted diagnoses by cytochrome b (cytb) sequencing and morphological identification, and estimated the levels of parasitaemia based on microscopy. We identified 6 cytb lineages infecting G. plebejus. Two of them were new lineages: Haemoproteus sp. GEPLE01 and GEPLE02. We also detected Haemoproteus sp. ZOCAP08, Haemoproteus sp. AMAVIR01, Plasmodium homopolare BAEBIC02 and Plasmodium cathemerium ZONCAP15. By microscopy, we detected Haemoproteus coatneyi, Haemoproteus erythrogravidus, P. homopolare and other unidentified species of Haemoproteus, Plasmodium, Babesia sp. and 1 microfilaria. We found no evidence of Leucocytozoon. Additionally, we detected several coinfections by sequencing and microscopy. The prevalence of haemosporidian infections was high (87.7%), and the mean parasitaemia was 61.65 infected cells per 10 000 erythrocytes examined. Prevalence and parasitaemia were higher for Haemoproteus than for Plasmodium. Haemoproteus sp. AMAVIR01 showed the highest prevalence (43.1%) and mean parasitaemia (94.39/10 000 erythrocytes) and might be associated with H. coatneyi. Immature individuals showed a lower prevalence than adults, supporting previous findings.

Molecular and serological detection of arthropod-borne pathogens in carnivorous birds from Brazil

Rickettsiales, Haemosporida and Rhizobiales agents can cause diseases that affect various animal species, including humans. Due to predation behaviour, carnivorous birds may play an important role in spreading these etiological agentes across geographically distant areas, specially if they are migratory. The aim of this study was to investigate the occurrence and to access the phylogenetic relations among Anaplasmataceae (Ehrlichia, Anaplasma, Neorickettsia), Bartonellaceae (Bartonella spp.), and Haemosporida (Plasmodium, Haemoproteus and Leucocytozoon) agents in blood samples from 121 carnivorous birds sampled in the states of São Paulo and Rio de Janeiro, Brazil. Inclusions resembling hemoparasites were not observed in Giemsa-stained preparations. While three animals were seropositive for E. chaffeensis (3.41% [3/88]; 95% CI:1.17-9.55%), five showed antibodies to A. phagocytophilum (5.68% [5/88]; 95% CI: 2.45-12.62%). Despite the detection of rrs gene fragments closely related to E. chaffeensis (4.13% [5/121]; 95% CI: 1.78-9.31%), no positivity was observed in the qPCR based on the genes vlpt for the organism. Similarly, 12 (9.91% [12/121]; 95% CI: 5.76-16.74%) samples were positive in the qPCR for Anaplasma spp. based on groEL gene, but negative in the qPCR for A. phagocytophilum based on msp-2 gene. Three samples were positive in the nPCR for E. canis based on rrs gene. Three samples were positive for Haemoproteus spp. and one for Plasmodium spp. in the nPCR based on cytB gene. Four birds (3.3% [4/121]; 95% CI: 1.29-8.19%) presented co-positivity by Ehrlichia sp. and Anaplasma sp. in molecular assays. One (0.82% [1/121]; 95% CI:0.15-4.53%) bird showed to be seropositive for E. chaffeensis and and positive in PCR for Haemoproteus sp. All birds were negative in the qPCR assay for Bartonella spp. (nuoG). The present work showed the occurrence of Anaplasmataceae agents and hemosporidians in carnivorous birds from southeastern Brazil. The role of these animals in the dispersion of Anaplasmataceae agents should be further investigated.

First molecular detection of piroplasmids in non-hematophagous bats from Brazil, with evidence of putative novel species

Piroplasmida is an order of the phylum Apicomplexa that comprises the Babesia, Cytauxzoon, and Theileria genera. These hemoparasites infect vertebrate blood cells and may cause serious diseases in animals and humans. Even though previous studies have shown that bats are infected by different species of piroplasmids, the occurrence and diversity of these hemoparasites have not been investigated in this group of mammals in Brazil. Therefore, the present work aimed to investigate the occurrence and assess the phylogenetic placement of piroplasmids infecting bats sampled in a peri-urban area from Central-Western Brazil. Seventeen (12.6%) out of 135 animals were positive by nested PCR assay for the detection of Babesia/Theileria targeting the 18S rRNA gene. Eleven sequences of the 17 positive samples could be analyzed and showed an identity of 91.8-100% with Theileria bicornis, Babesia vogeli, a Babesia sp. identified in a small rodent (Thrichomys pachyurus) from the Brazilian Pantanal and a Babesia sp. identified in a dog from Thailand as assessed by nBLAST. A phylogenetic tree was constructed from an alignment of 1399 bp length using analyzed and known piroplasmid 18S rRNA sequences. In this tree, piroplasmid 18S rRNA sequences detected in three specimens of Phyllostomus discolor (Piroplasmid n. sp., P. discolor) were placed as a sister taxon to Theileria sensu stricto (Clade V) and Babesia sensu stricto (Clade VI). An additional phylogenetic tree was generated from a shorter alignment of 524 bp length including analyzed piroplasmid 18S rRNA sequences of bat species Artibeus planirostris and A. lituratus (Piroplasmid sp., Artibeus spp.). The two 18S rRNA sequences detected in Artibeus spp. (Piroplasmid n. sp., Artibeus spp.) were placed within Babesia sensu stricto (Clade VI) into a strongly supported clade (bootstrap: 100) that included Babesia vogeli. The two 18S rRNA sequences of Piroplasmid sp., Artibeus spp. showed a single and a two-nucleotide differences, respectively, with respect to B. vogeli in a 709 pb length alignment. For the first time, the present study shows the occurrence of putative new piroplasmid species in non-hematophagous bats from Brazil.

Ehrlichia spp. and Anaplasma spp. in Xenarthra mammals from Brazil, with evidence of novel 'Candidatus Anaplasma spp.'

Anaplasmataceae agents are obligatory intracellular Gram-negative α-proteobacteria that are transmitted mostly by arthropod vectors. Although mammals of the Superorder Xenarthra (sloths, anteaters, and armadillos) have been implicated as reservoirs for several zoonotic agents, only few studies have sought to detect Anaplasmataceae agents in this group of mammals. This study aimed to investigate the occurrence and genetic diversity of Anaplasma spp. and Ehrlichia spp. in blood and spleen samples of free-living Xenarthra from four different states in Brazil (São Paulo, Mato Grosso do Sul, Rondônia, and Pará). Nested and conventional PCR screening assays were performed to detect the rrs and dsb genes of Anaplasma spp. and Ehrlichia spp., respectively. The assays were positive in 27.57% (91/330) of the Anaplasma spp. and 24.54% (81/330) of the Ehrlichia spp. Of the 91 positive Anaplasma spp. samples, 56.04% were positive in a conventional PCR assay targeting the 23S–5S intergenic region. Phylogenetic and distance analyses based on the rrs gene allocated Anaplasma sequences from sloths captured in Rondônia and Pará states in a single clade, which was closely related to the A. marginale, A. ovis, and A. capra clades. The sequences detected in southern anteaters from São Paulo were allocated in a clade closely related to sequences of Anaplasma spp. detected in Nasua nasua, Leopardus pardalis, and Cerdocyon thous in Brazil. These sequences were positioned close to A. odocoilei sequences. Genotype analysis corroborated previous findings and demonstrated the circulation of two distinct Anaplasma genotypes in animals from north and southeast Brazil. The first genotype was new. The second was previously detected in N. nasua in Mato Grosso do Sul state. The intergenic region analyses also demonstrated two distinct genotypes of Anaplasma. The sequences detected in Xenarthra from Pará and Rondônia states were closely related to those in A. marginale, A. ovis, and A. capra. Anaplasma spp. sequences detected in Xenarthra from São Paulo and were allocated close to those in A. phagocytophilum. The analyses based on the dsb gene grouped the Ehrlichia spp. sequences with sequences of E. canis (São Paulo, Mato Grosso do Sul, and Pará) and E. minasensis (Rondônia and Pará). The data indicate the occurrence of E. canis and E. minasensis and two possible new Candidatus species of Anaplasma spp. in free-living mammals of the Superorder Xenarthra in Brazil.

Haemosporidian Parasites of Chilean Ducks: The Importance of Biogeography and Nonpasserine Hosts

Biogeography is known to have shaped the diversity and evolutionary history of avian haemosporidian parasites across the Neotropics. However, a paucity of information exists for the temperate Neotropics and especially from nonpasserine hosts. To understand the effect of biogeography in the temperate Neotropics on haemosporidians of nonpasserine hosts we screened ducks (Anseriformes) from central Chile for the presence of these parasites. Forty-two individuals of 4 duck species (Anas flavirostris, Anas georgica, Mareca sibilatrix, Spatula cyanoptera cyanoptera) were collected and assessed for haemosporidian parasite infections by real-time polymerase chain reaction screening and subsequent sequencing of the mitochondrial cytochrome b gene. Haemoproteus (subgenus Haemoproteus) and Plasmodium were detected in 2 host species, A. georgica and S. c. cyanoptera, with no Leucocytozoon found. Overall haemosporidian prevalence was low (14.2%), with the prevalence of Plasmodium (11.9%) being substantially greater than that of Haemoproteus (4.8%). Six haemosporidian cytochrome b lineages were recovered, 2 Haemoproteus and 4 Plasmodium, with all 6 lineages identified for the first time. In phylogenetic reconstruction, the Chilean Plasmodium lineages were more closely related to South American lineages from passerine birds than to known lineages from anseriforms. The subgenus Haemoproteus known from nonpasseriformes has never been identified from any anseriform host; however, we recovered 2 lineages from this subgenus, one from each A. georgica and S. c. cyanoptera. Further work is needed to determine if this presents true parasitism in ducks or only a spillover infection. The results of phylogenetic reconstruction demonstrate a unique evolutionary history of these Chilean parasites, differing from what is known for this host group. The unique geography of Chile, with a large part of the country being relatively isolated by the Atacama Desert in the north and the Andes in the east and south, would present opportunities for parasite diversification. Further work is needed to investigate how strongly the biogeographical isolation has shaped the haemosporidian parasites of this area. Our results add to the growing body of evidence that nonpasserine hosts support unique lineages of haemosporidian parasites, while also demonstrating the role of biogeography in haemosporidian parasite diversity in the temperate Neotropics.

Serological and molecular detection of Anaplasma phagocytophilum in Thoroughbred horses from Chilean racecourses

Anaplasma phagocytophilum is the causative agent of equine granulocytic anaplasmosis (EGA). This study aimed to perform serological and molecular surveys of A. phagocytophilum in thoroughbred horses from racecourses in Chile. Additionally, hematological findings related to A. phagocytophilum molecular positivity were addressed, and phylogenetic analysis of selected positive samples was performed. Complete blood count and msp2 gene real-time PCR were performed in 457 thoroughbred horses from three racecourses located in three different cities of Chile (Santiago, Viña del Mar and Concepción). Sera from horses in two racecourses (Santiago and Vina del Mar) were tested by Indirect fluorescent antibody test (IFAT) to detect IgG antibodies against A. phagocytophilum. The occurrence of A. phagocytophilum by real-time PCR was 13.6 % (62/457, 95 % CI: 10.8-16.3 %), with the highest occurrence observed in Santiago (26.5 %), followed by Concepción (9%), and the lowest in Viña del Mar (5%). The overall frequency of IgG antibodies to A. phagocytophilum was 7.9 % (23/290, 95 % CI: 4.8-12.7 %), with 9.9 % in Santiago and 6.5 % in Viña del Mar. Only three animals from Santiago Racecourse were positive in both real-time PCR and serology. PCR-positive horses from Santiago racecourse presented significantly lower hemoglobin, mean corpuscular value (MCV), and mean corpuscular hemoglobin concentration (CHCM), and higher eosinophil counts. Phylogenetic analysis based on the msp2 gene showed that A. phagocytophilum sequences found in the present study were closely related with A. phagocytophilum sequences from the USA and Europe. Anaplasma phagocytophilum DNA is detected for the first time in Chile.

Molecular detection of vector-borne agents in cats in Southern Brazil

This study used serological and molecular methods to investigate the occurrence of vector-borne pathogens (VBP) with zoonotic potential in cats neutered at the University Veterinary Hospital in Canoinhas, Santa Catarina. The combined PCR and serological results revealed that 17 (56.6%) cats were positive for one or more pathogens. The sampled cats had antibodies to Ehrlichia spp. (7/30), Anaplasma phagocytophilum (3/30) and Leishmania infantum (2/30). The PCR assay detected DNA closely related to Ehrlichia canis in 6/30 cats, Mycoplasma haemofelis in 2/30 cats, A. phagocytophilum and Cytauxzoon sp. in one cat each. While Bartonella clarridgeiae and B. henselae were detected in two cats each, and B. koehlerae was detected in one cat.

Serological evidence of exposure to Toxoplasma gondii and Neospora caninum in free-ranging Orinoco goose (Neochen jubata) in Brazil

Toxoplasma gondii and Neospora caninum are Apicomplexan intracellular protozoan parasites that affect numerous animal species, thus leading to severe diseases and economic losses, depending on the vertebrate species involved. The role of the avian species in maintaining and transmission of these coccidia has been studied for several years as they tend to serve as a potential source of infection for mammals and humans. The present study aimed to assess the serological exposure of Orinoco goose (Neochen jubata) to T. gondii and N. caninum. Between 2010 and 2013, 41 free-ranging Orinoco geese were captured in the Araguaia River, Brazil. The presence and titration of IgY antibodies to both coccidia were assayed via indirect immunofluorescent antibody test (IFAT). While IgY antibodies for N. caninum were present in 5 animals, with titers of 20, the antibodies for T. gondii were found in 35 animals, with titers ranging from 20 to 640. Considering that the Orinoco goose's meat is consumed by the local population in the studied area, it may represent an important source of T. gondii infection for humans. Due to its migratory behavior, this goose may play a pivotal role in the natural dispersion of both parasites. Furthermore, molecular studies are required for genotyping the isolates of T. gondii that occurs in this avian species.

Pathological and molecular characterization of avian malaria in captive Magellanic penguins (Spheniscus magellanicus) in South America

Avian malaria is a mosquito-borne disease that affects multiple avian species and is caused by protozoans of the genus Plasmodium. An avian malaria infection caused by Plasmodium sp. in Magellanic penguins (Spheniscus magellanicus) with high mortality is described in a zoo in Southern Brazil. Clinically, three birds presented signs of inappetence, anorexia, pale mucosa, dyspnea, and opisthotonus, with death in a clinical course of 5-8 h. At the necropsy, all birds exhibited pale mucosa, marked splenomegaly and hepatomegaly, in addition to moderate leptomeningeal blood vessels ingurgitation in the brain. Microscopically, multiple exoerythrocytic meronts were observed in the cytoplasm of endothelial cells in the spleen, liver, heart, lungs, brain, kidneys, and pancreas. The spleen had a multifocal perivascular inflammatory infiltrate of lymphocytes, plasma cells, and macrophages, which also exhibited hemosiderosis and erythrophagocytosis. The liver had a multifocal periportal inflammatory infiltrate of lymphocytes, macrophages, and plasma cells, in addition to marked hemosiderosis in the hepatic sinusoids. Fragments of spleen, liver, brain, skeletal muscle, and lung were tested by the polymerase chain reaction technique for the detection of a fragment of the cytochrome B gene from haemosporidians, which resulted positive for Plasmodium spp. After sequencing, the samples were phylogenetically associated to Plasmodium sp. detected in Turdus albicollis (KU562808) in Brazil and matched to the lineage TURALB01 previously detected in T. albicollis. Avian malaria infections caused by Plasmodium sp. of lineage TURALB01 may occur in S. magellanicus with high mortality, and, thus, it is essential to detect and characterize the agent involved to obtain the differential diagnosis of the condition.

Detection of a putative novel genotype of Ehrlichia sp. from opossums (Didelphis aurita) from Brazil

Erlichiosis affects humans and animals worldwide. Its distribution and prevalence depends on the presence of tick vectors and hosts in one geographic area. The aim of the present study was to investigate the occurrence of Ehrlichia spp. and Anaplasma spp. in opossums (Didelphis sp.) from the State of Rio de Janeiro, southeast Brazil. Blood samples from 37 animals were tested for these two pathogens using molecular methods. One animal (2.7%) was positive for Ehrlichia sp. by 16S rRNA-based nested PCR. In a phylogenetic analysis based on the 16S rRNA gene using the maximum likelihood method and the GTRGAMMA+I evolutionary model, we detected a novel Ehrlichia sp. genotype closely related to genotypes of E. canis previously reported in dogs from Brazil. To the authors' knowledge, this is the first molecular detection of Ehrlichia sp. in opossums from this State in the southeastern region of the country.

Molecular detection of hemogregarines and haemosporidians in Brazilian free-living testudines

Morphological and molecular techniques were used to investigate the presence of hemogregarines and haemosporidians in biological samples of free-living Geoffroy's side-necked turtles (Phrynops geoffroanus) and Giant Amazon turtles (Podocnemis expansa) from Brazil. No evolutionary form of haemosporidians or hemogregarines were observed in the blood smears of 83 P. geoffroanus samples, and there were no meronts in the histological sections of 31 necropsied P. geoffroanus samples. All DNA samples extracted from P. geoffroanus tissues and blood aliquots were negative in haemosporidian PCR assays (based on the mitochondrial cytochrome b gene) and hemogregarine PCR assays (based on the 18S rRNA gene). In the analysis of blood smears of all seven Podocnemis expansa evaluated, gametocytes of hemogregarines were observed. The seven P. expansa were negative in the haemosporidian PCR assays. Moreover, hemogregarine DNA was detected in blood samples from all of the sampled P. expansa. The phylogenetic maximum likelihood inference and probabilistic Bayesian inference revealed five closely related genotypes that formed a monophyletic group. There was also a sister group to the lineage that consisted of Haemogregarina spp. of freshwater turtles from Canada, Italy, Mozambique, Kenya, Gabon, Vietnam, and China. The findings suggest that free-living P. expansa were parasitized by a new genotype or even a possible new species of the genus Haemogregarina. Haemosporidians and hemogregarines are not frequently found in P. geoffroanus in the studied region under the local conditions of that period.

Molecular detection of hemogregarines and haemosporidians in Brazilian free-living testudines

Morphological and molecular techniques were used to investigate the presence of hemogregarines and haemosporidians in biological samples of free-living Geoffroy's side-necked turtles (Phrynops geoffroanus) and Giant Amazon turtles (Podocnemis expansa) from Brazil. No evolutionary form of haemosporidians or hemogregarines were observed in the blood smears of 83 P. geoffroanus samples, and there were no meronts in the histological sections of 31 necropsied P. geoffroanus samples. All DNA samples extracted from P. geoffroanus tissues and blood aliquots were negative in haemosporidian PCR assays (based on the mitochondrial cytochrome b gene) and hemogregarine PCR assays (based on the 18S rRNA gene). In the analysis of blood smears of all seven Podocnemis expansa evaluated, gametocytes of hemogregarines were observed. The seven P. expansa were negative in the haemosporidian PCR assays. Moreover, hemogregarine DNA was detected in blood samples from all of the sampled P. expansa. The phylogenetic maximum likelihood inference and probabilistic Bayesian inference revealed five closely related genotypes that formed a monophyletic group. There was also a sister group to the lineage that consisted of Haemogregarina spp. of freshwater turtles from Canada, Italy, Mozambique, Kenya, Gabon, Vietnam, and China. The findings suggest that free-living P. expansa were parasitized by a new genotype or even a possible new species of the genus Haemogregarina. Haemosporidians and hemogregarines are not frequently found in P. geoffroanus in the studied region under the local conditions of that period.

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Hemogregarines was detected in blood samples of free-living Brazilian testudines.

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Gametocytes of hemogregarines were observed in Podocnemis expansa blood smears.

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Hemogregarines DNA fragments based on the 18S rRNA gene were detected in P. expansa.

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We propose that P. expansa were parasitized by a new genotype of Haemogregarina.

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Haemosporidians was not observed in either P. expansa or Phrynops geoffroanus samples.