The endogenous development of four new species of Isospora Schneider, 1881(Apicomplexa : Eimeriidae) from Australian geckos

Four new species of Isospora are described from Australian geckoes. Isospor a gehyrae n. sp. from Gehyra cf. variegata in South Australia have 18.5-22. 5x17.5-20.0 mum oocysts with 10.0-12.5x7.5-9.0 mum sporocysts; endogenous s tages develop in the host cell cytoplasm. Of the two species found in Heter onotia binoei from northern Queensland, Isospora cytoheteronotis n. sp., wi th oocysts of 20.0-26.0x17.5-25.0 mum and sporocysts of 10.0-13.5x7.5-11.5 mum, undergoes endogenous development in its host cell cytoplasm, whereas I . nucleoheteronotis n. sp., with oocysts of 17.5-22.5x17.5-21.5 mum and spo rocysts of 9.0-12.5x6.5-10.0 mum, develops in the host cell nucleus. I. oed urae n. sp. from Oedura rhombifer in northern Queensland has oocysts of 22. 5-25.0x22.5-24.0 mum and sporocysts of 12.5-14.0x7.5-11.5 mum, and undergoe s endogenous development in its host cell nuclei.