Power M L, Richter C, Emery S, Hufschmid J, Gillings M R
Department of Biological Sciences, Macquarie University, North Ryde, Sydney NSW 2109, Australia.
Exp Parasitol. 2009 Jun;122(2):165-8. doi: 10.1016/j.exppara.2009.02.008. Epub 2009 Feb 25.
Phylogenetic analysis of the genus Eimeria suggests that parasite and host have coevolved over broad evolutionary timescales. Here we extend this analysis by determining the 18S rDNA gene sequence of the marsupial coccidium, Eimeria trichosuri, and assessing its phylogenetic position relative to Eimeria from birds, reptiles and placental mammals. This analysis placed E. trichosuri clones in a clade that diverged before the major clade comprising species from placental mammals. The position of E.trichosuri is consistent with host phylogeny where marsupials represent an ancient evolutionary line that predates the placental mammal line.
艾美耳球虫属的系统发育分析表明，寄生虫和宿主在广泛的进化时间尺度上共同进化。在这里，我们通过确定有袋类球虫——毛滴虫艾美耳球虫的18S rDNA基因序列，并评估其相对于鸟类、爬行动物和胎盘哺乳动物的艾美耳球虫的系统发育位置，来扩展这一分析。该分析将毛滴虫艾美耳球虫克隆置于一个分支中，该分支在包含胎盘哺乳动物物种的主要分支之前就已经分化。毛滴虫艾美耳球虫的位置与宿主系统发育一致，有袋类代表了早于胎盘哺乳动物谱系的古老进化谱系。
