Vittori Miloš, Kostanjšek Rok, Znidaršič Nada, Strus Jasna
Department of Biology, Biotechnical faculty, University of Ljubljana, Večna pot 111, SI 1000 Ljubljana, Slovenia.
Zookeys. 2012(176):23-38. doi: 10.3897/zookeys.176.2285. Epub 2012 Mar 20.
Terrestrial isopods are a suitable group for the study of cuticle synthesis and calcium dynamics because they molt frequently and have evolved means to store calcium during molt. Little data is currently available on molting in Synocheta and subterranean isopods. We studied the molting dynamics in the subterranean trichoniscid Titanethes albus under laboratory conditions and performed a microscopic investigation of sternal CaCO(3) deposits and the tergal epithelium during molt in this species. In accordance with its lower metabolic rate, molting in the laboratory is roughly 2-3 times less frequent in Titanethes albus than would be expected for an epigean isopod under similar conditions. Animals assumed characteristic postures following the molt of each body half and did not consume the posterior exuviae after posterior molt. The structure of sternal calcium deposits and the ultrastructural characteristics of the epidermis during cuticle formation in Titanethes albus are similar to those described in representatives of Ligiidae. During the deposition of the exocuticle, the apical plasma membrane of epidermal cells forms finger-like extensions and numerous invaginations. In the ecdysial space of individuals in late premolt we observed cellular extensions surrounded by bundles of tubules.
陆生等足类动物是研究角质层合成和钙动力学的合适群体，因为它们蜕皮频繁，并且已经进化出在蜕皮期间储存钙的方式。目前关于Synocheta和地下等足类动物蜕皮的资料很少。我们在实验室条件下研究了地下毛等足类动物泰坦尼特白虫的蜕皮动力学，并对该物种蜕皮期间的胸骨碳酸钙沉积物和背板上皮进行了显微镜检查。与较低的代谢率一致，在实验室中，泰坦尼特白虫的蜕皮频率比在类似条件下的地表等足类动物预期的频率大约低2至3倍。动物在身体每一半蜕皮后呈现出特征性姿势，并且在后部蜕皮后不食用后部蜕壳。泰坦尼特白虫在角质层形成过程中胸骨钙沉积物的结构和表皮的超微结构特征与海蟑螂科代表物种中描述的相似。在外表皮沉积期间，表皮细胞的顶端质膜形成指状延伸和许多内陷。在蜕皮前后期个体的蜕皮空间中，我们观察到被小管束包围的细胞延伸。
