A number of parasitic protists and fungi have adopted extremely specialised characteristics of morphology, biochemistry, and molecular biology, sometimes making it difficult to discern their evolutionary origins. One aspect of several parasitic groups that reflects this is their metabolic organelles, mitochondria and plastids. These organelles are derived from endosymbiosis with an alpha-proteo...

Haemogregarines were recorded in caimans Caiman crocodilus yacare from Pantanal. This study was carried out in seasonal ponds at the Miranda- Abobral subregion of Pantanal, State of Mato Grosso do Sul, western Brazil, from 1998 to 1999. Smears from 28 caimans were examined and 20 (71.4%) presented infection by a haemogregarine. Infections were observed in 11 males and 9 females. Morphological a...

The Apicomplexa are a diverse group of intracellular parasitic protists. The majority of species from the classes Coccidea, Haemosporea and Piroplasmea are responsible for widespread diseases of humans and domestic animals. Oocysts of these parasites can persist for long periods of time in the environment (i.e. in water, soil, on vegetation and other food resources), maintaining their infectivi...

This study describes the community structure of the microbial eukaryotic community from hypersaline Lake Tyrrell, Australia, using near full length 18S rRNA sequences. Water samples were taken in both summer and winter over a 4-year period. The extent of eukaryotic diversity detected was low, with only 35 unique phylotypes using a 97% sequence similarity threshold. The water samples were domina...

Apicomplexan parasites are the causative agents of notorious human and animal diseases that give rise to considerable human suffering and economic losses worldwide. The most prominent parasites of this phylum are the malaria-causing Plasmodium species, which are widespread in tropical and subtropical regions, and Toxoplasma gondii, which infects one third of the world's population. These parasi...

Eighty-eight fecal samples from 2 species of pika, Ochotona collaris and Ochotona hyperborea, collected in Alaska (N = 53) and Russia (N = 35), respectively, were examined for the presence of coccidia (Apicomplexa: Eimeriidae). Five oocyst morphotypes were observed. In O. collaris, we found Eitmeria calentinei, Eimeria cryptobarretti, and Eimeria klondikensis, whereas in O. hyperborea, we found...