Büning Jürgen
Zoologisches Institut der Universität, Bade str. 9, D-4400 Münster, Federal Republic of Germany.
J Morphol. 1979 Oct;162(1):37-65. doi: 10.1002/jmor.1051620104.
Sialis flavilatera L. (Sialidae, Megaloptera) has telotrophic-meroistic ovarioles. The germ cells of the tropharium are organized into two distinct tissues, the central syncytium and the germ cell tapetum. The central syncytium consists of nurse cell nuclei embedded in a common cytoplasm which is rich in ribosomes and mitochondria. Cell membranes are totally absent. The germ cell tapetum surrounds the syncytium and consists of a monolayer of cells, each of which is connected with the central syncytium by an intercellular bridge. The oocytes differentiate from basal tapetum cells by previtellogenic growth. Their nutritive cords remain connected to the central syncytium by the intercellular bridge. Ovariole development starts soon after hatching with the immigration of germ cells into the ovariole-anlagen and is finished during pupal stages 23 months later. In apical regions of each tropharium, mitoses occur throughout larval life. The descendants enter the prophase of meiosis which lasts until pre-vitellogenesis; thus, a differential gradient of position and time is established. About 12 months after hatching, the central syncytium arises at the base of the tropharium from a membrane labyrinth in which intercellular bridges are entangled. Evidence is presented that endopolyploidization does not occur during germ cell differentiation. Finally, the results are compared with those found in Hemiptera and polyphage Coleoptera. The great diversities are interpreted as an indication for a polyphyletic origin of the telotrophic ovary.
黄边泥蛉（Sialis flavilatera L.，泥蛉科，广翅目）具有端滋式meroistic卵巢管。营养区的生殖细胞组织成两种不同的组织，即中央合胞体和生殖细胞绒毡层。中央合胞体由嵌入富含核糖体和线粒体的共同细胞质中的滋养细胞核组成。完全没有细胞膜。生殖细胞绒毡层围绕着合胞体，由单层细胞组成，每个细胞通过细胞间桥与中央合胞体相连。卵母细胞通过卵黄发生前的生长从基部绒毡层细胞分化而来。它们的营养索通过细胞间桥与中央合胞体相连。卵巢管发育在孵化后不久随着生殖细胞迁移到卵巢管原基开始，并在23个月后的蛹期完成。在每个营养区的顶端区域，有丝分裂在整个幼虫期都有发生。其后代进入持续到卵黄发生前的减数分裂前期；因此，建立了位置和时间的差异梯度。孵化后约12个月，中央合胞体在营养区基部由一个细胞间桥相互缠绕的膜迷路形成。有证据表明在生殖细胞分化过程中不会发生内多倍体化。最后，将结果与半翅目和多食性鞘翅目中的结果进行比较。这些巨大的差异被解释为端滋式卵巢多系起源的一个迹象。
