Hirudiniformes

Taxobox
name = Hirudiniformes

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image_width = 240px
image_caption = "Haemopis" species (Haemopidae) in Danube-Auen National Park
regnum = Animalia
subregnum = Eumetazoa
phylum = Annelida
classis = Clitellata
subclassis = Hirudinea
infraclassis = Euhirudinea
ordo = Arhynchobdellida
subordo = Hirudiniformes
subordo_authority =
subdivision_ranks = Families
subdivision =
Cylicobdellidae

Haemadipsidae
Haemopidae
Hirudinidae
Semiscolecidae
Xerobdellidae

synonyms =Gnathobdellae
Gnathobdellida Vaillant, 1890
(but see text)

The Hirudiniformes are one of the currently-accepted suborders of the proboscisless leeches (Arhynchobdellida). Their most well-known member is the European Medical Leech, "Hirudo medicinalis", and indeed most of the blood-sucking "worms" as which leeches are generally perceived belong to this group. In general, though some leeches suck blood, many are predators which hunt small invertebrates however.

The Arhynchobdellida were formerly divided into two groups, denoted by presence or absence of toothed jaws. But this does not represent a natural division, as has now been determined - the most primitive proboscisless leeches are not found among the jawed blood-sucking forms as was generally believed, but among the jawless predators.

"Jawed leeches" - termed "Gnathobdellae" or "Gnathobdellida" - are exclusively found among the Hirudiniformes, but the order contains a number of jawless families as well. The jawed, toothed forms make up the aquatic Hirudidae and the terrestrial Haemadipsidae and Xerobdellidae (sometimes included in the preceding but worthy of recognition as an independent family). These might actually form a clade, which would then be placed at superfamily rank [The taxon would thus become "Gnathobdelloidea" according to ICZN rules, but the issue has neither been sufficiently studied nor formally proposed.] , but it seems that the Hirudidae might rather be close relatives of the carnivorous Haemopidae instead.Borda "et al." (2008)]

Many of the most well-known leeches belong to this family, most notably the medical leeches, such as the European species, already mentioned, which is prominent among these. Other medical Hirudiniformes of lesser importance are for example other species of the genus "Hirudo", the North American Medical Leech ("Macrobdella decora"), and the Asian Medical Leech ("Hirudinaria manillensis"). Among the more well-known bloodsucking land leeches are the Indian Leech ("Haemadipsa sylvestris") and the "yamabiru" or Japanese Mountain Leech ("Haemadipsa zeylanica").

Footnotes

References

* (2008): On the classification, evolution and biogeography of terrestrial haemadipsoid leeches (Hirudinida: Arhynchobdellida: Hirudiniformes). "Mol. Phylogenet. Evol." 46(1): 142–154. doi|10.1016/j.ympev.2007.09.006 (HTML abstract)