Departamento de Biologia Celular, Centro Interdisciplinar de Investigação Marinha e Ambiental, Instituto de Ciências Biomédicas Abel Salazar, Universidade do Porto, Porto, Portugal.
Mem Inst Oswaldo Cruz. 2010 Mar;105(2):203-7. doi: 10.1590/s0074-02762010000200016.
A myxosporean parasite in the gill lamellae of the freshwater teleost fish, Sciades herzbergii (Ariidae) (Block, 1794), from the Poti River (Northeast of Brazil) was described by light and electron microscopy studies. Polysporic histozoic cyst-like plasmodia containing several life-cycle stages, including mature spores, were observed. The spores were pyriform and uninucleate, measuring 9.15 +/- 0.39 microm (n = 50) long, 4.36 +/- 0.23 microm (n = 25) wide and 2.61 +/- 0.31 microm (n = 25) thick. Elongated pyriform polar capsules (PC) were of equal size (4.44 +/- 0.41 microm long and 1.41 +/- 0.42 microm in diameter) and each contained a polar filament with 9-10 coils obliquely arranged in relation to the axis of PC. The PC wall was composed of two layers of different electron densities. Histological analysis revealed the close contact of the cyst-like plasmodia with the basal portion of the epithelial gill layer, which exhibited some alterations in the capillary vessels. Based on the morphological and ultrastructural differences, the similarity of the spore features to those of the genus Myxobolus and the specificity of this host to previously described species, we describe a new species named Myxobolus sciades n. sp. in this study.
通过光镜和电镜研究，描述了一种存在于淡水硬骨鱼 Sciades herzbergii（ Ariidae ）（Block，1794）鳃小片上的粘孢子虫寄生虫。观察到多孢子的组织内包囊样原生质团，其中包含几个生活史阶段，包括成熟孢子。孢子呈梨形，单核，长 9.15±0.39μm（n=50），宽 4.36±0.23μm（n=25），厚 2.61±0.31μm（n=25）。伸长的梨形极囊（PC）大小相等（长 4.44±0.41μm，直径 1.41±0.42μm），每个极囊内都有一条极丝，由 9-10 个线圈斜向排列在极囊轴上。极囊壁由两层不同电子密度的物质组成。组织学分析显示，包囊样原生质团与鳃上皮层的基底部分密切接触，而毛细血管在该处发生了一些改变。基于孢子的形态和超微结构差异、与 Myxobolus 属孢子特征的相似性以及该宿主与先前描述的物种的特异性，我们在本研究中描述了一个新种，命名为 Sciades 粘孢子虫 Myxobolus sciades n. sp.。
