First record of an intraleucocytic haemogregarine (Adeleorina: Haemogregarinidae) from South African tortoises of the species Stigmochelys pardalis (Cryptodira: Testudinidae)
To date, four intraerythrocytic apicomplexans, namely the haemogregarines Haemogregarina fitzsimonsi and Haemogregarina parvula, and the haemoproteids Haemoproteus testudinalis and Haemoproteus natalensis, have been described from South African land tortoises. Recently, an intraleucocytic haemogregarine was observed in one species of tortoise, Stigmochelys pardalis, from the province of KwaZulu-Natal. Gamonts were identified in the monocytes and lymphocytes of 5/126 (4%) S. pardalis, but no additional stages were detected. Mixed infections with H. fitzsimonsi were observed for 2/5 (40%) of the parasitized S. pardalis, but the intraleucocytic gamont stages were larger than the intraerythrocytic gamont stages of both H. fitzsimonsi and H. parvula. The only other record of a chelonian intraleucocytic haemogregarine is of Haemogregarina pseudemydis, with stages described from the red and white blood cells of neotropical terrapins. Thus, the report of an intraleucocytic haemogregarine infecting a terrestrial tortoise from Africa is significant, although its taxonomic placement remains problematic at present.
Key words: intraleucocytic, haemogregarine, tortoise blood parasite, SouthAfrican, apicomplexan taxonomy.