Glossiphoniidae are a
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
of freshwater proboscis-bearing leeches. These leeches are generally flattened, and have a poorly defined
anterior sucker. Most suck the
blood
Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood in the cir ...
of freshwater
vertebrate
Vertebrates () comprise all animal taxa within the subphylum Vertebrata () (chordates with backbones), including all mammals, birds, reptiles, amphibians, and fish. Vertebrates represent the overwhelming majority of the phylum Chordata, with c ...
s like
amphibians,
crocodilians
Crocodilia (or Crocodylia, both ) is an order of mostly large, predatory, semiaquatic reptiles, known as crocodilians. They first appeared 95 million years ago in the Late Cretaceous period (Cenomanian stage) and are the closest living ...
and
aquatic turtle
Turtles are an order of reptiles known as Testudines, characterized by a special shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked t ...
s, but some feed on
invertebrate
Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate ...
s like
oligochaete
Oligochaeta () is a subclass of animals in the phylum Annelida, which is made up of many types of aquatic and terrestrial worms, including all of the various earthworms. Specifically, oligochaetes comprise the terrestrial megadrile earthworm ...
s and
freshwater snails instead. Although they prefer other hosts, blood-feeding species will opportunistically feed from humans.
There is considerable interest in the
symbiotic bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometr ...
that at least some glossiphoniids house in specialized organs called
bacteriomes. The bacteria are thought to provide the leeches with nutrients that are scarce or absent from their regular diets. ''
Haementeria'' as well as ''
Placobdelloides'' have
Enterobacteriaceae symbionts, while ''
Placobdella'' harbours peculiar and independently derived
alphaproteobacteria
Alphaproteobacteria is a class of bacteria in the phylum Pseudomonadota (formerly Proteobacteria). The Magnetococcales and Mariprofundales are considered basal or sister to the Alphaproteobacteria. The Alphaproteobacteria are highly diverse and ...
.
Systematics and taxonomy
The relationships between members of Glossiphoniidae are not completely understood. Some sources divide the group into three subfamilies, while many divide the family directly into genera. Genera are listed below, with subfamily given in brackets.
* ''
Actinobdella''
Moore, 1901 (Subfamily Haementariinae)
* ''
Alboglossiphonia''
Lukin, 1976 (Subfamily Haementariinae)
* ''
Desserobdella''
Barta & Sawyer, 1990 (Subfamily Glossiphoniinae)
* ''
Gloiobdella''
Ringuelet, 1978 (Subfamily Haementariinae)
* ''
Glossiphonia''
Johnson, 1817 (Subfamily Glossiphoniinae)
* ''
Haementaria''
de Filippi, 1849 (Subfamily Haementariinae)
* ''
Hellobdella''
Blanchard, 1896 (Subfamily Haementariinae)
* ''
Marvinmeyeria''
Soós, 1969 (Subfamily Haementariinae)
* ''
Oligobdella''
Moore, 1918 (Subfamily Haementariinae)
* ''
Placobdella''
Blanchard, 1893 (Subfamily Glossiphoniinae)
* ''
Placobdelloides''
Sawyer, 1986
* ''
Theromyzon''
Philippi, 1867 (Subfamily Theromyzinae)
* ''
Torix''
Blanchard, 1893
Genera listed are based on consensus between the
Encyclopedia of Life
The ''Encyclopedia of Life'' (''EOL'') is a free, online encyclopedia intended to document all of the 1.9 million living species known to science. It is compiled from existing trusted databases curated by experts and with the assistance of ...
, the
Catalogue of Life
The Catalogue of Life is an online database that provides an index of known species of animals, plants, fungi, and microorganisms. It was created in 2001 as a partnership between the global Species 2000 and the American Integrated Taxonomic I ...
, and the Univeristy of Michigan's
Animal Diversity Web
Animal Diversity Web (ADW) is an online database that collects the natural history, classification, species characteristics, conservation biology, and distribution information on thousands of species of animals. The website includes thousands ...
. Other sources, however, such as
GBIF
or
ITIS
give more or fewer genera.
Ecology and behavior
Glossiphoniid leeches exhibit remarkable
parental care
Parental care is a behavioural and evolutionary strategy adopted by some animals, involving a parental investment being made to the evolutionary fitness of offspring. Patterns of parental care are widespread and highly diverse across the animal ki ...
, the most highly developed one among the known
annelids. They produce a membranous bag to hold the eggs, which is carried on the underside. The young attach to the parent's belly after hatching and are thus ferried to their first meal.
Certain Glossiphoniidae parasitize amphibian species. For example, some members of the Glossiphoniidae are known to attack the inner oral cavity of the
Rough-skinned Newt
The rough-skinned newt or roughskin newt (''Taricha granulosa'') is a North American newt known for the strong toxin exuded from its skin.
Appearance
A stocky newt with rounded snout, it ranges from light brown to olive or brownish-black on ...
.
[C.M. Hogan, 2008]
Medical importance
While glossiphoniids do not preferentially feed on humans, they are nonetheless of medical interest. As with all blood- or haemolymph-feeding leeches, their
saliva, contains
anticoagulant compounds which are potentially useful in therapy of some
cardiovascular diseases.
Antistasin and related inhibitors of
thrombokinase a such as
ghilanten,
lefaxin and
therostatin have been derived from ''
Haementeria'' species and ''
Theromyzon tessulatum''. These substances also may prevent certain
tumor
A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...
s from
metastasizing. Also from ''Haementeria'' are the
fibrin stabilizing factor a inhibitor
tridegin, a
platelet
Platelets, also called thrombocytes (from Greek θρόμβος, "clot" and κύτος, "cell"), are a component of blood whose function (along with the coagulation factors) is to react to bleeding from blood vessel injury by clumping, thereby i ...
adhesion
Adhesion is the tendency of dissimilar particles or surfaces to cling to one another ( cohesion refers to the tendency of similar or identical particles/surfaces to cling to one another).
The forces that cause adhesion and cohesion can b ...
inhibitor (
leech anti-platelet protein; LAPP), and the
fibrinogen
Fibrinogen (factor I) is a glycoprotein complex, produced in the liver, that circulates in the blood of all vertebrates. During tissue and vascular injury, it is converted enzymatically by thrombin to fibrin and then to a fibrin-based blood cl ...
-dissolving
enzyme
Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...
s
hementin Hementin is an anticoagulant protease (fibrinogen lytic enzyme) from the salivary glands of the giant Amazon leech (''Haementeria ghilianii''). Hementin is a calcium-dependent protease with a molecular weight of 80-120 kDa, and it contains 39 amin ...
and
hementerin. ''T. tessulatum'' also yields
therin,
theromin and
tessulin, which inhibit
protease
A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalyzes (increases reaction rate or "speeds up") proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the ...
activity.
Ornatins, which are
antiplatelet glycoprotein IIb-IIIa
antagonists, were discovered in ''
Placobdella ornata'', and several species have yielded
hyaluronidase
Hyaluronidases are a family of enzymes that catalyse the degradation of hyaluronic acid (HA). Karl Meyer classified these enzymes in 1971, into three distinct groups, a scheme based on the enzyme reaction products. The three main types of hyal ...
s.
Line notes
References
*
Joel Cracraft
Joel Lester Cracraft (born July 31, 1942), is an American paleontologist and ornithologist. He received a PhD in 1969 from Columbia University (''Functional Morphology of Locomotion in Birds'').
His research interests include: theory and method ...
and Michael J. Donoghue (2004) ''Assembling the Tree of Life'', Oxford University Press, USA, 592 pages
* C. Michael Hogan (2008) ''Rough-skinned Newt ("Taricha granulosa")'', GlobalTwitcher, ed. N. Stromber
{{Taxonbar, from=Q4471004
Leeches
Annelid families
Taxa named by Léon Vaillant