The use of an integrative approach to identify coelomocytes in three species of the genus <i>Holothuria</i> (Echinodermata)

Coelomocytes in the Holothuroidea are traditionally identified according to their morphology through light, fluorescence, or electron microscopy. Former studies have typically used only one method, with few works combining two more approaches. Studies using cytocentrifugation study these cells scarcer. Thus, for first time, an integrative approach was compare coelomocytes Holothuroidea. This consisted of living and stained cells, scanning microscopy (for spherule cells), accurate morphometric analyses. Specifically, we specimens Holothuria grisea, arenicola, tubulosa test whether could be valuable comparative coelomocytes, help understand cell diversity, closely related species, even those having distinct geographic distributions ecological requirements, would a similar population coelomocytes. Our results showed seven types including phagocytes, fusiform morula acidophilic spherulocytes, progenitor crystal cells. Total differential counts, along parameters, were among species. Morphometric analyses revealed consistent differences diameter cytoplasmic spherules, as well set different morphotypes spherulocytes spherulocytes. Cytospin preparations proved quite useful because they provided constant morphological data, allowing identification comparisons Moreover, this highlighted (1) that is good parameter separate (2) putative maturation process Lastly, species very similar, regardless distribution ecology. our work contributes better understanding Holothuria, genus wide distribution. The present may establish important model organisms, bring insights into functions