Diplectanid monogeneans are gill parasites that can infect fish in huge numbers and thus become harmful. especially in maricultured fish. It is therefore useful to have taxonomic tools. such as keys. https://www.roneverhart.com/Gretsch-G5210T-P90-Electromatic-Jet-Two-90-Single-Cut-Electric-Guitar-w-Bigsby-Mako-p23063/