This work is the first ultrastructural study of spermatozoa in a species of Digenea belonging to the genus Labracetabulum. Labracetabulum gephyroberici parasitizes the digestive tract of the teleost fish Gephyroberyx darwinii (Trachichtyidae) captured in the Atlantic Ocean near Dakar (Senegal). This is also the first report of L. gephyroberici from Senegal. The mature spermatozoon is filiform tapered at both ends and exhibits the general organization described in most Opecoelideans, namely two axonemes of the 9 + “1” pattern of the Trepaxonemata, an anterior electron-dense material, an external ornamentation associated with a row of cortical microtubules, spine-like bodies, two mitochondria and two bundles of cortical microtubules. However, the mature spermatozoon of L. gephyroberici exhibits some particularities: a short first axoneme which does not reach the nuclear region and the position of the second mitochondrion which reaches almost the posterior part of the mature spermatozoon. The second mitochondrion is still present after the disappearance of the second axoneme. The morphology of the posterior extremity corresponds to the Opecoelidean type described by Quilichini et al. (2010).

这项工作是对属于Labracetabulum属的Digenea物种中精子的首次超微结构研究。Labracetabulum gephyroberici寄生于在达喀尔（塞内加尔）附近的大西洋中捕获的硬骨鱼darwinii（Trachichtyidae）的消化道。这也是L的第一个报告。双歧杆菌来自塞内加尔。成熟的精子在两端呈丝状渐细，并表现出大多数Opecoelideans所描述的一般组织，即Trepaxonemata的9 +“ 1”型两个轴突，一种前电子致密材料，与一排皮质相关的外部装饰微管，脊柱状体，两个线粒体和两束皮质微管。然而，L的成熟精子。双歧杆菌表现出一些特殊性：一个短的第一轴突不到达核区域，第二个线粒体的位置几乎到达成熟精子的后部。在第二个轴突消失后，第二个线粒体仍然存在。后肢的形态与Quilichini等人描述的Opecoelidean类型相对应。（2010）。