目的:异孢子菌属的成员通常感染多种野生鸟类。通过结合形态测量和遗传数据,我们能够区分和描述一种新的顶复体寄生虫,鱼黄异孢菌n.sp.,来自安大略省的北部黄轴闪烁(Colaptesauratusluteus),加拿大。
方法:在尸检期间获得的肠内容物中观察到未孢子形成的卵囊;这些卵囊在室温下在7天内完成外源性孢子形成。完整的核18SrDNA和完整的线粒体基因组序列是从这个先前未描述的Isosporasp。与相关球虫进行比较。
结果:成孢子的卵囊形状为亚球形,平均为22.7×21.7μm(n=53;平均形状指数1.05),含有近球形极性颗粒。孢子呈卵形至椭圆形,测量17.0×10.5μm的平均尺寸(n=9;平均形状指数1.62)。孢子囊残留物集中在一个不规则的,每个孢子囊中间的球形质量。分离的卵囊在形态上与据报道感染Picidae家族成员的其他Isospora物种不同。基于使用结合的核18SrDNA和线粒体细胞色素C氧化酶I(COI)序列或完整的线粒体基因组序列的系统发育分析,这个Isosporasp.n.从NorthernFlicker中分离出来,该进化枝包含从各种盘形宿主描述的Isospora物种。
结论:基于结合的形态学和分子数据,在黄鱼的胃肠道内容物中发现的卵囊代表了一种新的异孢子菌,在此称为异孢子菌。
OBJECTIVE: Members of the genus Isospora commonly infect a wide variety of wild birds. By combining morphometric and genetic data, we are able to differentiate and describe a new apicomplexan parasite, Isospora picoflavae n. sp., from the Northern Yellow-shafted Flicker (Colaptes auratus luteus) in Ontario, Canada.
METHODS: Unsporulated oocysts were observed in intestinal contents obtained during necropsy; these oocysts completed exogenous sporulation within 7 days at room temperature. Complete nuclear 18S rDNA and complete mitochondrial genome sequences were obtained from this previously undescribed Isospora sp. to compare with related coccidia.
RESULTS: Sporulated oocysts were subspherical in shape measuring an average of 22.7 × 21.7 μm (n = 53; mean shape index 1.05) containing a near-spherical polar granule. Sporocysts were ovoidal to ellipsoidal in shape, measuring an average size of 17.0 × 10.5 μm (n = 9; mean shape index 1.62). Sporocyst residuum was concentrated in an irregular, spherical mass in the middle of each sporocyst. The isolated oocysts differed morphologically from other Isospora species reported to infect members of the family Picidae. Based on phylogenetic analyses using either combined nuclear 18S rDNA and mitochondrial cytochrome c oxidase I (COI) sequences or complete mitochondrial genome sequences, this Isospora sp. n. isolated from the Northern Flicker grouped within a clade containing Isospora species described from various passeriform hosts.
CONCLUSIONS: Based on combined morphological and molecular data, the oocysts found in the gastrointestinal contents of Colaptes auratus luteus represent a new species of Isospora named herein as Isospora picoflavae n. sp.