The myticalin database includes a manually curated collection of the nucleotide and protein sequences of myticalins, a family of linear cationic antimicrobial peptides displaying strong gill-specificity first described in marine mussels (Mytilus spp.) by Leoni and colleagues in 2017. The collection derives from the combined analysis of genomic and transcriptomic information from multiple species belonging to the Mytilus complex (Mytilus galloprovincialis, Mytilus edulis, Mytilus trossulus and Mytilus chilensis), and their congeners Mytilus californianus and Mytilus coruscus. The sequences are currently classified within five major subfamilies (A, B, C, D and E) based on strict phylogenetic criteria and their amino acid composition.