Viola arvensis is a species of violet known by the common name field pansy. It is native to Europe, western Asia, and North Africa, and it is known on other continents as an introduced species and a weed of disturbed and cultivated areas.
Viola arvensis was shown to contain cyclotides, a class of peptides found in plants. The peptide cycloviolacin O2 in particular has shown to possess cytotoxic activity against human cancer cells and is therefore looked at as a potential drug lead.