Arredondo Nathalia J, Gil de Pertierra Alicia A
Laboratorio de Helmintología, Departamento de Biodiversidad y Biología Experimental, Facultad de Ciencias Exactas y Naturales, Ciudad Universitaria, Int. Güiraldes 2160, Pabellón II, 4o Piso, Universidad de Buenos Aires, C1428EGA - Buenos Aires, Argentina.
Folia Parasitol (Praha). 2012 Jun;59(2):99-106. doi: 10.14411/fp.2012.015.
Margaritaella gracilis gen. n. et sp. n. (Proteocephalidea: Proteocephalinae) found in the intestine of Callichthys callichthys (Linnaeus) from the Paraná River basin is described. The new genus is placed in the Proteocephalinae because of the medullary position of the genital organs. It differs from all known genera included in the Proteocephalinae by the following combination of characters: 1) scolex with a conspicuous cluster of drop-shaped gland cells posterior to suckers; 2) strobila with a low number of proglottides, all much longer than wide; 3) testes arranged in one field, composed of two parallel rows of testes separated by the uterus; 4) ovary delicate, H-shaped, with branches slender and deeply folliculate at the edges, located at 25-35% from the posterior end; 5) uterus largely extended posterior to the ovary but not reaching the end of proglottis; and 6) vitelline follicles in two narrow lateral bands, largely extended posterior to the ovary. Scanning electron microscopy revealed three types of microtriches on the tegument surface: acicular and capiliform filitriches and gladiate spinitriches. The relative size of the ovary, a character recently used in the systematics of the proteocephalidean cestodes, was calculated for the new species and compared with other species of the group. M. gracilis is the first record of a proteocephalidean cestode parasitizing a callichthyid catfish.
描述了在巴拉那河流域的丽鱼科美丽丽鱼（Callichthys callichthys，Linnaeus）肠道中发现的细丽头绦虫属（Margaritaella）新属新种（Proteocephalidea: Proteocephalinae）。由于生殖器官位于髓质位置，该新属被置于头槽绦虫亚科。它与头槽绦虫亚科中所有已知属的区别在于以下特征组合：1）头节在吸盘后方有明显的滴状腺细胞簇；2）链体节片数量少，所有节片均长大于宽；3）睾丸排成一列，由子宫分隔成两排平行的睾丸；4）卵巢精致，呈H形，分支细长，边缘有深滤泡，位于后端25 - 35%处；5）子宫在卵巢后方大幅延伸，但未到达节片末端；6）卵黄滤泡位于两条狭窄的侧带，在卵巢后方大幅延伸。扫描电子显微镜显示体表有三种微毛：针状和丝状毛细微毛以及剑状棘微毛。计算了新物种卵巢的相对大小，这是头槽绦虫系统分类中最近使用的一个特征，并与该类群的其他物种进行了比较。细丽头绦虫是寄生在丽鱼科鲶鱼体内的头槽绦虫的首次记录。
