On blood parasites and South American marsupials: Parasitological biogeography and phylogeny in support of evolution

MERINO, S.; MARTÍNEZ, J.; VÁSQUEZ, R. A.; SLAPETA, J.; CELIS-DIEZ, J. L.; GUTIÉRREZ-JIMÉNEZ, L.; IPPI, S.; SÁNCHEZ-MONSALVEZ, I.; MARTÍNEZ-DE LA PUENTE, J.

Valencia, España

Congreso; II Congreso de la Sociedad Española de Biología Evolutiva; 2009

Sociedad Española de Biología Evolutiva

The Microbiotheriid "Monito del Monte" (Dromiciops gliroides) is the only living representative of this group of South American marsupials. Inspection of blood smears from specimens of "Monito del Monte" captured at Chiloé Island in Chile have been searched for blood parasites and a Hepatozoon species infecting red blood cells has been detected. The sequences of DNA fragments corresponding to small subunit ribosomal RNA gene revealed two parasitic lineages belonging to Hepatozoon genus. These parasite lineages showed a basal position with respect to Hepatozoon species infecting rodents, reptiles and amphibians but are phylogenetically distinct from species infecting the order Carnivora. The potential vector of this parasite appear to be the host-specific tick Ixodes neuquenensis since the sequencing of a long amplicon determined the presence of one of the two lineages found in the marsupial. All these data point out to an ancestral host-parasite relationship between the parasite and the marsupial host. In addition, we found that intraerythrocytic parasites (Apicomplexa: Sarcocystidae) of the South American mouse opossum (Thylamys elegans) from Chile, South America, and of the yellow-bellied glider (Petaurus australis) from Australia were monophyletic using SSU rDNA and partial LSU rDNA sequences. These parasites represent an as yet unnamed genus and it is expected to have bisporocystic oocysts and tetrazoic sporocysts, which is a characteristic feature of all members of the family Sarcocystidae. These results show that erythrocytic parasites share a common ancestor and suggest co-evolution with their vertebrate host. In addition, we found that intraerythrocytic parasites (Apicomplexa: Sarcocystidae) of the South American mouse opossum (Thylamys elegans) from Chile, South America, and of the yellow-bellied glider (Petaurus australis) from Australia were monophyletic using SSU rDNA and partial LSU rDNA sequences. These parasites represent an as yet unnamed genus and it is expected to have bisporocystic oocysts and tetrazoic sporocysts, which is a characteristic feature of all members of the family Sarcocystidae. These results show that erythrocytic parasites share a common ancestor and suggest co-evolution with their vertebrate host. In addition, we found that intraerythrocytic parasites (Apicomplexa: Sarcocystidae) of the South American mouse opossum (Thylamys elegans) from Chile, South America, and of the yellow-bellied glider (Petaurus australis) from Australia were monophyletic using SSU rDNA and partial LSU rDNA sequences. These parasites represent an as yet unnamed genus and it is expected to have bisporocystic oocysts and tetrazoic sporocysts, which is a characteristic feature of all members of the family Sarcocystidae. These results show that erythrocytic parasites share a common ancestor and suggest co-evolution with their vertebrate host. In addition, we found that intraerythrocytic parasites (Apicomplexa: Sarcocystidae) of the South American mouse opossum (Thylamys elegans) from Chile, South America, and of the yellow-bellied glider (Petaurus australis) from Australia were monophyletic using SSU rDNA and partial LSU rDNA sequences. These parasites represent an as yet unnamed genus and it is expected to have bisporocystic oocysts and tetrazoic sporocysts, which is a characteristic feature of all members of the family Sarcocystidae. These results show that erythrocytic parasites share a common ancestor and suggest co-evolution with their vertebrate host. In addition, we found that intraerythrocytic parasites (Apicomplexa: Sarcocystidae) of the South American mouse opossum (Thylamys elegans) from Chile, South America, and of the yellow-bellied glider (Petaurus australis) from Australia were monophyletic using SSU rDNA and partial LSU rDNA sequences. These parasites represent an as yet unnamed genus and it is expected to have bisporocystic oocysts and tetrazoic sporocysts, which is a characteristic feature of all members of the family Sarcocystidae. These results show that erythrocytic parasites share a common ancestor and suggest co-evolution with their vertebrate host.