Milanin Tiago, Atkinson Stephen D, Silva Márcia R M, Alves Roberto G, Maia Antônio A M, Adriano Edson A
Acta Parasitol. 2017 Mar 1;62(1):121-128. doi: 10.1515/ap-2017-0014.
The involvement of oligochaetes in the life cycles of fresh water myxozoan parasites in Brazil was investigated. Of 333 oligochaetes collected in a fish farm in the State of São Paulo, three (0.9%) released Aurantiactinomyxon type spores. From 86 worms collected in a fish farm in Mato Grosso do Sul State, 1 (0.9%) released actinospores with a novel morphology for which we propose the name Seisactinomyxon. Infected oligochaetes were identified by morphology: all belonged to family Naididae, with Pristina americana the host for Aurantiactinomyxon and Slavina evelinae the host of Seisactinomyxon. This is the first report of the involvement these two species of oligochaetes in the life cycle of myxozoans. Small subunit rDNA sequences of the Aurantiactinomyxon (1204 nt) and Seisactinomyxon (1877 nt) did not match any previously sequenced myxozoan. Phylogenetic analyses showed that both actinospore types fell in a clade formed by six Myxobolus spp. that parasitize Characiformes fishes.
对巴西淡水粘孢子虫寄生虫生命周期中寡毛纲动物的参与情况进行了调查。在圣保罗州一个养鱼场收集的333条寡毛纲动物中，有3条（0.9%）释放出橙黄放射孢子虫属类型的孢子。在南马托格罗索州一个养鱼场收集的86条蠕虫中，有1条（0.9%）释放出具有新形态的放射孢子，我们将其命名为六放放射孢子虫。通过形态学鉴定受感染的寡毛纲动物：所有均属于仙女虫科，美洲原仙女虫是橙黄放射孢子虫的宿主，伊氏斯拉维仙女虫是六放放射孢子虫的宿主。这是关于这两种寡毛纲动物参与粘孢子虫生命周期的首次报道。橙黄放射孢子虫（1204个核苷酸）和六放放射孢子虫（1877个核苷酸）的小亚基核糖体DNA序列与任何先前测序的粘孢子虫均不匹配。系统发育分析表明，这两种放射孢子类型都属于由六种寄生于脂鲤科鱼类的粘体虫属物种形成的一个分支。
