RESUMO

Adeleorinid parasites commonly infect turtles and tortoises in nature. Currently, our knowledge about such parasites is extremely poor. Their characterization is based on morphological and molecular approaches using the 18S rDNA molecular marker. However, there is a limitation with the 18S rDNA due to its slow rate of evolution. For that reason, the goals of this study were to 1) design primers for new molecular mitochondrial markers to improve the phylogenetic reconstructions of adeleorinid parasites and 2) to determine the morphological and genetic diversity of Haemogregarina infecting turtles and tortoises in Colombia. Turtles from 16 species representing six families were examined for the presence of haemoparasites. We analyzed 457 samples using PCR, and 203 of them were also analyzed by microscopy. Using a mitochondrial genome of Haemogregarina sequenced in this study, we designed primers to amplify fragments of the cytochrome oxidase I (coxI), cytochrome oxidase III (coxIII), and cytochrome b (cytb) mitochondrial markers in adeleorinid parasites. Lineages obtained from nuclear and mitochondrial molecular markers clustered according to the turtle lineages from which they were isolated. It is noteworthy that we found different evolutionary lineages within the same morphotype, which may indicate heteroplasmy and/or cryptic diversity in Haemogregarina. Due to this situation, we could not make a species delimitation, even when integrating the different lines of evidence we had in this study. However, the primers presented here are useful for diagnosis and, moreover, according to the available information, all three genes retain phylogenetic signals; thereby fragments amplified can be used in reconstructing evolutionary relationships. This effort contributes to the knowledge of the diversity of these parasites infecting continental turtles from Colombia.

Assuntos

Coccidiose/veterinária , Código de Barras de DNA Taxonômico , Eucoccidiida/fisiologia , Genoma Mitocondrial , Tartarugas , Animais , Coccidiose/diagnóstico , Colômbia , Eucoccidiida/classificação , Eucoccidiida/genética , Filogenia , RNA de Protozoário/análise , RNA Ribossômico 18S/análise

RESUMO

The genus Haemocystidium was described in 1904 by Castellani and Willey. However, several studies considered it a synonym of the genera Plasmodium or Haemoproteus. Recently, molecular evidence has shown the existence of a monophyletic group that corresponds to the genus Haemocystidium. Here, we further explore the clade Haemocystidium spp. by studying parasites from Testudines. A total of 193 individuals belonging to six families of Testudines were analyzed. The samples were collected in five localities in Colombia: Casanare, Vichada, Arauca, Antioquia, and Córdoba. From each individual, a blood sample was taken for molecular analysis, and peripheral blood smears were made, which were fixed and subsequently stained with Giemsa. The prevalence of Haemocystidium spp. was 1.55% (n = 3/193); all infected individuals belonged to Podocnemis vogli (Savanna Side-necked turtle) from the department of Vichada. This is the first report of Haemocystidium spp. in Colombia and in this turtle species. The phylogenetic analysis of a mitochondrial cytb fragment revealed Haemocystidium spp. as a monophyletic group and as a sister taxon of Haemoproteus catharti and the genus Plasmodium. Haemocystidium spp. are difficult to identify by morphology only. As a result, it is possible that some of the taxa, such as Haemocystidium (Simondia) pacayae, represent a species complex. The parasite found in our study is morphologically indistinguishable from Haemocystidium (Simondia) pacayae reported in Peru. However, the new lineage found in P. vogli shows a genetic distance of 0.02 with Hae. pacayae and 0.04 with Hae. peltocephali. It is proposed that this divergent lineage might be a new species. Nevertheless, additional molecular markers and ecological features could support this hypothesis in the future.