A histological procedure for the study of insect chitinized tissues in light microscopy

We present a procedure to obtain histological preparations of insect cuticles for their observation in ligth microscopy. The use of EDTA (ethylendiaminetetraacetic acid), as a chelator of certain metals present in chitin, soften the tissues and allows us to cut them. The tissues were embbeding in plastic resines in two different protocols and cutted by cryostat (20–30 μm) and ultramicrotome (4 μm) respectively. This procedure, based on traditional histology products, allows us to obtain preparations observable under an optical microscope, facilitating the study of the internal structure of the cuticule, e.g. visualizing the different layers or structures such as glands or setae. •EDTA allows softening chitinous tissues under certain pH conditions.•Softening of chitin allows us to process it with classical histology procedures.•Cuts of 20–30 microns show us the internal structure of chitin in light microscopy.