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The Classification of Haemopis Grandis

Leeches may look slimy, but these bloodsucking worms have a cultural and scientific value that belies their common reputation. Modern-day physicians, for instance, use leeches to aid recovery from plastic surgery and to cure black eyes; the hirudin produced in their saliva may have applications in treating inner-ear disorders and as an anti-coagulant. Among the largest leech species is Haemopis grandis.

Taxonomic Classification
- Earthworms are members of the same biological class as leeches: Clitellata.
  
  The genus Haemopis belongs to subfamily Haemopinae and family Haemopidae, according to the federal Integrated Taxonomic Information System. These terms all use the Latin root "haemo-" (sometimes spelled "hemo-" or "hema-"), which means "blood," alluding to the leeches' feeding habits. Family Haemopidae belongs to suborder Hirudiniformes, order Arhynchobdellida, and subclass Hirudinea; the subclass belongs to class Clitellata, which also includes earthworms. Class Clitellata belongs to phylum Annelida, the segmented worms; Annelida includes some 12,000 known species of worm. Phylum Annelida belongs, of course, to the kingdom Animalia.
Anatomical Classification
- Biologists group these worms according to their anatomy; the leech is second from the left.
  
  Leeches, including H. grandis, are segmented worms. These common invertebrates have "skin" that is a thick cuticle of collagen and a long, straight digestive tract that extends from the mouth in one end to the anus at the other. Unlike some other worms, however, leeches are hermaphroditic, meaning that each creature has the reproductive organs of both male and female. H. grandis can be classified among the larger annelids. It grows to between five and ten inches long, with a thick ribbon-like body.
Ecological Classification
- Unlike other bloodsuckers, like mosquitoes, H. grandis lacks a proboscis, using its muscular jaws to extract blood.
  
  H. grandis is indigenous to North America, specifically the fresh waters of Canada and the northern U.S., where the colder water is higher in oxygen, required for these larger leeches to breathe. H. grandis belongs to an order (Arhynchobdellida) that lacks the needle-like proboscis of some leeches. Instead, members of Arhynchobdellida have tripartite muscular jaws, which they use to feed upon the blood of other animals. Its prey is widely varied, including crustaceans, tadpoles, insects and other worms; it is both a predator and a scavenger.
Medicinal Classification
- Cardiologists have found that the hirudin produced by H. grandis and related leeches can help prevent dangerous blood clots.
  
  Like other jawed leeches, H. grandis secretes hirudin, which keeps the blood from coagulating as it sucks its meals. Leech-produced anti-coagulants can be "administered to cardiac patients to inhibit clot formation and to destroy existing clots respectively," according to Lander University's Richard Fox; after centuries of folk medicine, H. grandis and related leeches are the subject of at least two biomedical companies. Despite an appearance that humans may find unpleasant, there is no scientific evidence suggesting that leech bites -- either accidental or medically intended -- spread disease.

Animals & Science