[1][2][3] Arhynchobdellida is a diverse order, compromising both aquatic and terrestrial, besides sanguivorous and predatory, leeches.

[3] The order is divided into two suborders, Erpobdelliformes and Hirudiniformes (sometimes also called the Pharyngobdelliformes and Gnathobdelliformes, respectively).

[5][6] Current taxonomy accepts the order Arhynchobdellida and divides into two suborders.

[7] The placement of Americobdellidae is uncertain; it has rudimentary jaws and is terrestrial.Erpobdelliformes are jawless predators of aquatic invertebrates of varying sizes, including insect larvae, mollusks, and other annelids.

[1] Hirudiniformes are a diverse suborder defined by the presence of toothed jaws.