| Abstract: | Histological and ultrastructural analysis of polytrophic ovary structure in Neuroptera revealed an unusual organization of their germ cell clusters. In all species under study (representing 5 families), clusters with variable and unfixed numbers of cystocytes are formed. Moreover, spatial organization of cystocyte connections within the cluster is linear rather than typically branched; only a few branching sites being observed. The oocyte is located in the central, always linear, part of the cluster and therefore is directly connected via intercellular bridges with only two nurse cells. It is postulated here that the linear character of germ cell clusters in Neuroptera may result from asynchrony of cystocyte divisions. Mechanisms of germ cell cluster formation and differentiation are discussed. |
