Channel catfish Ictalurus punctatus from a commercial farming operation in the Mississippi Delta were submitted for examination for the presence of infection by the trematode Bolbophorus damnificus. The fish were instead found to possess skin nodules suggestive of Henneguya pellis, a species previously described in the blue catfish I. furcatus. Despite the dermal location and distribution of lesions, morphological characteristics of the myxospores were inconsistent with H. pellis. Spores possessed a lanceolate spore body 15.4 +/- 1.5 microm (mean +/- SD; range = 12.2-19.3 microm) in length and 5.5 +/- 0.6 microm (range = 4.5-6.8 microm) in width in valvular view, and 4.7 +/- 0.2 microm (range = 4.2-5.0 microm) in width in sutural view. Polar capsules were pyriform and unequal in both length and width and contained polar filaments with six coils. Polar capsules measured 6.1 +/- 0.8 microm (range = 4.0-7.9 microm) long and 1.7 +/- 0.3 microm (range = 1.0-2.2 microm) wide. The caudal appendages were 50.5 +/- 8.3 microm (range = 34.8-71.4 micorm) long and the total length of the spore was 65.9 +/- 8.6 microm (range = 48.2-90.0 microm). The "blister like" plasmodia were round or ovoid, up to 2 mm in diameter, and randomly distributed throughout the epidermis of the fish. Histologically, plasmodia were confined to the dermis and elicited no inflammatory reaction from the fish. A blast search of the 18S small subunit rDNA sequence obtained by polymerase chain reaction amplification resulted in no identical sequence matches but indicated a close relationship to H. gurlei, H. ictaluri, and H. exilis. The unique host record, spore morphology, and novel genetic sequence derived from this isolate lead us to propose this isolate as a novel species, H. sutherlandi.

中文翻译：

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通过形态学、组织学和分子特征描述的沟鲶新种

来自密西西比河三角洲商业养殖场的鲶鱼 Ictalurus punctatus 被提交检查是否存在吸虫感染。相反，这些鱼被发现具有暗示 Henneguya pellis 的皮肤结节，这是一种先前在蓝鲶 I. furcatus 中描述的物种。尽管病变的真皮位置和分布，粘孢子的形态特征与 H. pellis 不一致。孢子拥有披针形孢子体 15.4 +/- 1.5 microm（平均 +/- SD；范围 = 12.2-19.3 microm）在瓣膜视图中的长度和 5.5 +/- 0.6 microm（范围 = 4.5-6.8 microm），和4.7 +/- 0.2 microm（范围 = 4.2-5.0 microm）在缝合视图中的宽度。极性胶囊是梨形的，长宽不等，含有具有六个线圈的极性细丝。极性胶囊测量 6.1 +/- 0.8 微米（范围 = 4.0-7.9 微米）长和 1.7 +/- 0.3 微米（范围 = 1.0-2.2 微米）宽。尾附属物是 50.5 + /-8.3 microm （范围 = 34.8-71.4 microm） 长和孢子的总长度是 65.9 + /-8.6 microm （范围 = 48.2-90.0 microm）。“水泡状”疟原虫呈圆形或卵圆形，直径可达 2 毫米，随机分布在鱼的整个表皮中。组织学上，疟原虫被限制在真皮中，不会引起鱼的炎症反应。对通过聚合酶链反应扩增获得的 18S 小亚基 rDNA 序列进行爆炸搜索，没有发现相同的序列匹配，但表明与 H. gurlei、H. ictaluri 和 H. exilis 有密切关系。独特的寄主记录、孢子形态、