Laboratory of Evolutionary Biology, Ecology and Management of Ecosystems, Faculty of Sciences and Techniques, Cheikh Anta Diop University of Dakar, Senegal.
Tissue Cell. 2013 Dec;45(6):428-33. doi: 10.1016/j.tice.2013.07.006. Epub 2013 Aug 27.
The Mesometridae includes only five genera and eight species. The available data on the ultrastructure of sperm cells of mesometrid species referred to two species only, Elstia stossichianum and Wardula capitellata. The present study revealed the ultrastructure of the spermatozoon of a third genus and third species of Mesometridae, Centroderma spinosissima. The mature spermatozoon of C. spinosissima presents two axonemes with different lengths of the Ehlers' 9 + '1' trepaxonematan pattern, a nucleus, two mitochondria, two bundles of parallel cortical microtubules, external ornamentation of the plasma membrane, a lateral expansion, spine-like bodies, cytoplasmic ornamented buttons and granules of glycogen. The spermatozoon of C. spinosissima is similar to those of the previously studied mesometrids. However, some peculiarities such as the presence of two mitochondria, the disposition of the external ornamentation of the plasma membrane and the morphology of the posterior spermatozoon extremity, characterize the male gamete of C. spinosissima. Moreover, the presence of cytoplasmic ornamented buttons is a characteristic found only in the mature spermatozoon of mesometrids and it probably represents an autapomorphy for this family.
Mesometridae 科仅包括五个属和八个种。有关 Mesometridae 物种精子细胞超微结构的现有数据仅涉及两个种，即 Elstia stossichianum 和 Wardula capitellata。本研究揭示了第三个属和第三个种的 Mesometridae，Centroderma spinosissima 的精子超微结构。C. spinosissima 的成熟精子呈现出具有不同长度的 Ehlers' 9 + '1' 三射轴丝模式的两个轴丝、一个核、两个线粒体、两个平行的皮质微管束、质膜的外部装饰、侧向扩展、刺状体、细胞质装饰按钮和糖原颗粒。C. spinosissima 的精子与先前研究过的 Mesometridae 的精子相似。然而，一些特征，如两个线粒体的存在、质膜外部装饰的布置以及后精子末端的形态，使 C. spinosissima 的雄性配子具有特征。此外，细胞质装饰按钮的存在仅在 Mesometridae 的成熟精子中发现，这可能是该科的一个独特特征。
