MORPHOLOGICAL AND QUANTITATIVE STUDIES OF THE HEMOCYTES IN NYMPH AND IMAGO OF BLAPTICA DUBIA (SERVILLE, 1839)

Abstract

The purpose of the research is to analyze how the hemocyte counts and their morphological characteristics change during development of Blaptica dubia, especially during molting. And to suggest a possible scheme of the transformation of spherulocytes into crescent-cells. Materials and methods. Quantitative and morphological features of hemocytes of imago and nymphs of 1-4 stages of Blaptica dubia using light microscopy and AFM were researched. Cell, nucleus and granule sizes were determined using NIS-Elements and NOVA software. Cytochemical tests with neutral red and alcyan blue allowed us to identify different cell types. Results. This study presents a classification of hemocytes in Blaptica dubia, that based on morphological and cytochemical characteristics of cells. We analyzed the dynamics of the hemocytes counts in 6 nymphs (1-4 stages) and 6 imago. Special attention is given to the moment of molting. Seven hemocyte types were described and identified as: prohemocytes, plasmocytes, granulocytes, vermicytes, spherulocytes, coagulocytes and crescent-cells. The stem cells (prohemocytes) and spherulocytes were the predominant hemocytes. Prohemocytes counts decrease as a result of insect development, instead the relative number of plasmocytes and granulocytes increases. Spherulocytes counts could increase to 35% at the moment of leaving the ootheca and at the molting period. Due to the study of hemocytes diversity in different nymph stages, interim cells and possible ways of their transformations were identified. The unusual crescent-cells, that were unique for Gromphadorhina portentosa, had been found in Blaptica dubia. For the first time, the cytochemical test allowed to determine the origin of crescent-cells from spherulocytes.