A new Haemoproteid of Malaysian Microchiroptera (Hepatochstis rodhaini n. sp.) is described; it is classified in the genus Hepatocystis because of the morphology of its gametocytes and tissue schizonts.
Hepatocystis bainae n. sp., parasite on the Microchiropteran bat, Hipposideros galeritus is described and differentiated from Hepatocystis rodhaini; it is characterized by the type of the microgametocytes ("diffuse"), the small size of the hepatic schizonts and the repartition of the colloide.
Malaysian Sciuridae are often parasitised by 2 species of Hepatocystis which were described as a single species Hepatocystis vassali malayensis by Field and Edeson, (1950). One of them corresponds to the majority of forms seen by Field and Edeson; it is redescribed herein and raised to specific status: H. v. malayensis becomes H. malayensis Field and Edeson, 1950. By the morphological characteristics of its gametocytes and schizonts, H. malayensis is related to H. kochi. The evolution of tissue schizonts studied at liver biopsies and autopsies of squirrels captured shortly before examination is of a peculiar type: an immunological tissue reaction appears with the hyperinfestation of the Rodents and controls the growth of the schizonts.
Hepatocystis brayi n. sp. is described and separated from the second species parasitising Malaysian Sciuridae, H. malayensis Field and Edeson, 1950. H. brayi is characterized by: 1) the evolution of its tissue schizonts which are intracellular throughout all their development; the cytoplasm and the nucleus of the host cell are highly hypertrophied; 2) the scarcity of the colloid. The schizogony persists for several months in the liver of infected animals and the gametocytaemia apparently undergoes seasonal relapses. H. brayi is a parasite of hosts occurring in the middle and under canopy, H. malayensis the middle and top canopy.
Eimeria nebulosa n. sp. and Klossia pachyleparon n. sp. are described from the monitor lizard Varanus nebulosus in Malaysia. The flask shaped oocysts of E. nebulosa average 20.7 by 12.6 mum. The oocyst wall is composed of a single layer. There is a single polar granule but no residuum. Ellipsoidal sporocysts average 11.1 by 5.6 mum. A sporocyst residuum is present. Endogenous stages develop in the epithelial cells of the small intestine. The splerical oocysts of K. pachyleparon average 33.6 mum in diameter. The wall is about 2.5 mum thick and is composed of 3 layers. The spherical sporocysts average 10.8 mum in diameter. Sporocysts contain 4 sporozoites and residuum. Developmental stages were not observed.
Leucocytozoon coracinae sp. nov. is described from the avian family Campephagidae and Hepatozoon apodis sp. nov. from the Apodidae. The distribution of these parasites within their respective families is discussed.