Myrmicacin (3-hydroxydecanoic acid) is a chemical compound of the ò-hydroxycarboxylic acid class. It is named after the South American leaf-cutter ants (Myrmicinae) in which it was first discovered, but is also found in royal jelly. Myrmicacin is believed to act as a herbicide which prevents seeds collected by the ants from germinating within the nest.