Unique Morphogenesis in the Damp-Wood Termite: Abscission of the Stylus during Female Reproductive Caste Differentiation
Unique Morphogenesis in the Damp-Wood Termite: Abscission of the Stylus during Female Reproductive Caste Differentiation
复制标题
DOI：
10.2108/zs190056
复制
发表时间：
2019-10
影响因子：
0.9
通讯作者：
K. Oguchi;T. Miura
中科院分区：
文献类型：
--
作者：
K. Oguchi;T. Miura
真社会性昆虫根据劳动分工和种姓分化来组织它们的群体，其中种姓特异性的形态在胚后发育期间被雕刻。在生殖种姓与不育种姓的分化过程中，生殖种姓的交配和生殖相关特征得到发展，而中性种姓的交配和生殖相关特征则退化，但对生殖种姓分化过程中的发育规律却知之甚少。众所周知，在某些白蚁物种中，腹部后端的感觉突出物（触针）在雌性生殖器中消失。在本研究中，我们进行了解剖学和组织学分析，在湿木白蚁Hodotermopsis sjostedti阐明的发展过程中的幼态和有翅分化的触针消失的基础。虽然最初假设，在扩大的第七胸骨柄下隐藏的花柱，我们的观察结果发现，在生殖女性的花柱完全丢失。进一步的组织学观察表明，针消失不是由退化过程完成的;相反，针从腹部分离，并在蜕皮过程中与外骨骼（蜕皮）一起丢弃到生殖种姓。这种活组织在发育过程中被丢弃的现象被认为是一种脱落现象，如在植物叶片中所见。
Eusocial insects organize their colonies based on division of labor and caste differentiation, in which caste-specific morphologies are sculpted during postembryonic development. In the differentiation between reproductive and sterile castes, characteristics related to mating and reproduction are developed in reproductives, and degenerated in neuters, although little is known about the developmental regulations during the differentiation. In some species of termites, a sensory protrusion at the posterior end of the abdomen, the stylus, is known to disappear in female reproductives. In the present study, we performed anatomical and histological analyses in the damp-wood termite Hodotermopsis sjostedti to elucidate the developmental process underlying the disappearance of the stylus during neotenic and alate differentiation. Although it was first hypothesized that styli were hidden beneath the enlarged seventh sternite, our observation results found out that the styli were completely lost in reproductive females. Further histological observations revealed that the stylus disappearance was not accomplished by degeneration process; rather, styli were separated from the abdomen and discarded with the exoskeleton (exuviae) during the molt into the reproductive caste. This phenomenon in which live tissues are discarded through developmental processes is suggested to be a case of abscission, as seen in plant leaves.