Protocolo de recolecta y tinción para el estudio taxonómico de los policládidos (Platyhelminthes: Polycladida)

The taxonomic study of polyclads (order Polycladida) dates back to the 19th century. The traditional taxonomy of these organisms requires a combination of the external and internal morphology of the body and the hermaphroditic reproductive system, where the histological techni que is an indispensable tool that plays a key role in this process. This protocol covers the collection processes up to the preparation of the specimens for histological analysis,adapting and improving techniques previously established by other authors for clear and precise visualization of the anatomical structures. Specimens are collected manually using fine paintbrush, photographed dorsally and ventrally, fixed in 10% frozen formalin neutralized with sodium borate and preserved in 70° ethanol. For taxonomic classification, complete mounts of the organisms and sagittal sections of the hermaphroditic reproductive system are used; a five-step histological protocol including hydration, staining, dehydration/differentiation, cleaning/transparency, and slide mounting is performed for each. This standardized technique complements morphological and taxonomic studies of the taxon.