抄録
Ascogregarines are protozoan parasites of the phylum Apicomplexa, which generally infect insects. So far fourteen species of Ascogregarina have been reported from Culicidae, Psychodidae and Phoridae. In view of the difficulty to identify the parasite by optical microscopic study, the scanning electron microscopic study of the oocysts and gamont stage of the parasite has been undertaken. Besides, the sequencing of ITSI and ITSII region of ribosomal DNA was done as a supportive method of molecular identification of the paraiste. The study revealed a new Ascogregarina parasite, which was found to infect Ochlerotatus j. japonicus. The new Ascogregarina species, e. g. Ascogregarina japonicus demonstrated significant differences in the oocysts and gamonts structure as well as the in its nucleotide sequences of ITSI and ITSII region from the other two well known ascogregarine parasites e. g. A. culicis and A. taiwanensis. In Japan, since Ae. albopictus and Oc. japonicus japonicus often share their larval habitats, the cross infection of the two host by the two different ascogregarine parasites may happen in nature. Therefore, a study of cross infection was also conducted considering the aforesaid two hosts and the two parsites. All the findings will serve as basic bio-molecular information in the field of Ascogregarina research.
Key words: New Ascogregarina sp., Ochlerotatus japonicus japonicus, oocysts, ITSI, ITSII.
