The Family Hirudinidae is commonly known as the leech family, and includes a diverse array of bloodsucking invertebrates. While leeches are often associated with medicine and bloodletting, they play an important role in aquatic ecosystems as decomposers and predators. Synonyms for the Family Hirudinidae include the hirudineans, hirudineids, and simply the leeches. These synonyms are used interchangeably within scientific literature to refer to the same group of organisms. With over 650 species spread across the world, the leech family is an important and fascinating component of the animal kingdom.