family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
of
hematophagous
Hematophagy (sometimes spelled haematophagy or hematophagia) is the practice by certain animals of feeding on blood (from the Greek words αἷμα ' "blood" and φαγεῖν ' "to eat"). Since blood is a fluid tissue rich in nutritious pro ...
leech
Leeches are segmented parasitic or predatory worms that comprise the subclass Hirudinea within the phylum Annelida. They are closely related to the oligochaetes, which include the earthworm, and like them have soft, muscular segmented bodie ...
es which live on the
mucous membrane
A mucous membrane or mucosa is a membrane that lines various cavities in the body of an organism and covers the surface of internal organs. It consists of one or more layers of epithelial cells overlying a layer of loose connective tissue. It is ...
s of
mammal
Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...
s and sometimes invertebrates. These are internal
parasites
Parasitism is a Symbiosis, close relationship between species, where one organism, the parasite, lives on or inside another organism, the Host (biology), host, causing it some harm, and is Adaptation, adapted structurally to this way of lif ...
that enter the body through natural orifices (usually
nasal cavities
The nasal cavity is a large, air-filled space above and behind the nose in the middle of the face. The nasal septum divides the cavity into two cavities, also known as fossae. Each cavity is the continuation of one of the two nostrils. The nasal c ...
and
pharynx
The pharynx (plural: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the oesophagus and trachea (the tubes going down to the stomach and the lungs). It is found in vertebrates and invertebrates, though its struc ...
, more rarely the
lower respiratory tract
The respiratory tract is the subdivision of the respiratory system involved with the process of respiration in mammals. The respiratory tract is lined with respiratory epithelium as respiratory mucosa.
Air is breathed in through the nose to th ...
,
anus
The anus (Latin, 'ring' or 'circle') is an opening at the opposite end of an animal's digestive tract from the mouth. Its function is to control the expulsion of feces, the residual semi-solid waste that remains after food digestion, which, d ...
,
urethra
The urethra (from Greek οὐρήθρα – ''ourḗthrā'') is a tube that connects the urinary bladder to the urinary meatus for the removal of urine from the body of both females and males. In human females and other primates, the urethra con ...
, and
vagina
In mammals, the vagina is the elastic, muscular part of the female genital tract. In humans, it extends from the vestibule to the cervix. The outer vaginal opening is normally partly covered by a thin layer of mucosal tissue called the hymen ...
), and cause hirudiniases.
These species are characterized by a reduced number of teeth, and a posterior
sucker
Sucker may refer to:
General use
* Lollipop or sucker, a type of confection
* Sucker (slang), a slang term for a very gullible person
* Hard candy
** Cough drop
** Mint (candy)
Biology
* Sucker (botany), a term for a shoot that arises undergro ...
larger than the previous one. The latter may be involved in fixation on moist surfaces such as mucous membranes.
A 2017 paper discovered they did not exclusively infest mammals; individuals were recorded feeding on a Japanese freshwater crab, '' Geothelphusa dehaani.''
Genera
The ''Interim Register of Marine and Non-marine Genera''IRMNG taxon details: Praobdellidae Sawyer, 1986 (retrieved 31 August 2021) and ''WoRMS'' include:
# '' Praobdella'' Blanchard, 1896
# '' Parapraobdella'' Phillips, Oosthuizen & Siddall, 2011
# '' Tyrannobdella'' Phillips et al., 2010
* Some authorities also include '' Limnatis'' Moquin-Tandon, 1827 here, together with other genera provisionally placed in the