Arhynchobdellida, the proboscisless leeches, are a monophyletic order of leeches. They are defined by the lack of the protrusible proboscis that defines their sister taxon, the Rhynchobdellida.[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).[1]
| Proboscisless leeches | |
|---|---|
 | |
| A giant Americobdella species from southern Chile. | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Annelida |
| Clade: | Pleistoannelida |
| Clade: | Sedentaria |
| Class: | Clitellata |
| Subclass: | Hirudinea |
| Infraclass: | Euhirudinea |
| Order: | Arhynchobdellida Blanchard, 1894 |
| Suborders | |
| Synonyms | |
Arhynchobdellae Stuart, 1982[verification needed] | |
Taxonomy
Historically, the Arhynchobdellida were split into two orders, the Gnathobdellida and the Pharyngobdellida.[4] The Gnathobdellida were jawed and carnivorous or parasitic while the Pharyngobdellida were jawless and carnivorous.[5][6] Current taxonomy accepts the order Arhynchobdellida and divides into two suborders. There are 215 species of Arhynchobdellid leech, in 47 genera and 13 families.[7] The placement of Americobdellidae is uncertain; it has rudimentary jaws and is terrestrial.
Erpobdelliformes
Erpobdelliformes are jawless predators of aquatic invertebrates of varying sizes, including insect larvae, mollusks, and other annelids.[8][9] Unlike other leeches, they do not penetrate the skin of hosts; and are not at all parasitic.[10][11] The pharynx is spirally twisted and very large to allow for large prey; it can constitute up to one third of the leech's body length.[1]
Hirudiniformes
Hirudiniformes are a diverse suborder defined by the presence of toothed jaws.[1][11]
Cladogram
| Hirudinea |
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Source:[12]
References
