Hematophages (from other Greek. Αἷμα - “ blood ” + φάγος - “eater”) - animals that feed on the blood of other animals and humans. Hematophages can be carriers of certain pathogenic agents. Hematophagy is one of the most common forms of parasitism .
Content
Protists
Of the protists, trophozoites of the dysenteric amoeba and some other parasitic protists with phagocytosis of red blood cells are classified as hematophagous.
Annelids
Among annelids, many types of leeches are hematophages. They feed on the blood of vertebrates , mollusks , worms , etc. In their intestines, blood is digested slowly, and therefore, pumped, leeches can remain without food for a long time.
Nematodes
Hematophages are also parasitic representatives of the nematode type, in particular species from the Ancylostomatidae family, for example Ancylostoma duodenale and Necator americanus . In patients with hookworm infections , even with a moderate intensity of invasion , iron deficiency anemia naturally associated with hematophagy of the pathogen naturally develops.
Arthropods
Crustaceans
Among representatives of the crustacean subtype, hematophagy is found in carnivores ( Branchiura ), which are ectoparasites of marine and freshwater fish , less often amphibians. They can not be considered permanent parasites, as, having fed up, carpoeids leave the fish.
Arachnids
Among arachnids, hematophagy is characteristic of many ticks ( gamasid ticks , ixodid ticks , etc.).
Of spiders, a craving for blood was seen in the species Evarcha culicivora , which prefers to feed on blood-saturated hematophagous insects.
Insects
Among insects, hematophagy occurs in dipterans , bugs , fleas , lice . In bugs, it arose on the basis of predation - the entomophagy of ancestral forms, in dipterans - on the basis of saprophagy ( coprophages ). Lice hematophagy dates back to primary saprophagy ( keratophagy ), and the development of flea hematophagy was based, most likely, on the initial mixed type of nutrition of ancestral forms - predation and saprophagy.
Among the dipterans - the family Culicidae (female mosquitoes ), Nematocera , Brachycera and Orthorrhapha , horseflies (females of most species drink the blood of warm-blooded animals: mammals and birds), midges ( Simulidae ). Among bugs, hematophagy is found among representatives of the Bed bugs family, as well as in a number of tropical species from the Predator family, which feed on insects and blood of warm-blooded animals and humans (they represent a transition from predators to parasites ).
As an exception for the order of Lepidoptera , for adults of some tropical species of butterflies from the genus Calyptra as part of the scoop family, feeding on the blood and tear fluid of mammals is known. For example, Calyptra eustrigata , living in the territory from India to Malaysia ; and Calyptra thalictri , Calyptra lata . Males feed on tear fluid and blood of large animals. In these species, the proboscis tip is strongly sclerotized and modified to pierce mammalian skin and nourish blood [1] .
Vertebrates
Pisces
Hematophages are the few known species of fish , which include the so-called “parasitic catfish” - vandelli catfish from the subfamily Vandelliinae , the pygid family ( Trichomycteridae ), and the catfish order ( Siluriformes ) [2] . Some of them drill the skin of fish and other animals, sucking blood from the soft tissues, while others feed on the blood produced in the gill cavity of other fish. There are nine species in about four genera: Paracanthopoma (1 species), Paravandellia (2 species), Plectrochilus (3 species), Vandellia (3 species). Three species of Vandellia living in Brazil, including the common Vandellia , or the whiskered Vandellia ( Vandellia cirrhosa ), notorious for the name "Candira", can mistakenly climb into the urethra of the vertebral, focusing on the smell of ammonia (which also stands out from the gills of fish in breathing process), with serious consequences for both the prey and the fish itself.
Birds
Blood birds feed on species that are or were animal cleaners. Buffalo starlings , for example, prefer ticks that are full of blood. A sharp-billed earthen finch ( Geospiza difficilis ), living in the Galapagos, pecks the base of the feathers of nesting birds on seabird islands and drinks the blood flowing from the wounds.
Mammals
Among mammals, hematophagy occurs in the subfamily of vampire bats . These include three species: an ordinary vampire , a desmod ( Desmodus rotundus ), a white-winged vampire ( Diaemus youngi ), and a leggy vampire ( Diphylla ecaudata ). All of them are common in Central and South America from Mexico to northern Argentina . Other bats, called "vampires" ( Vampyrum spectrum , Vampyressa , Vampyrodes ), have no relation to hematophagy, eating either small vertebrates ( Vampyrum spectrum ), or fruits and insects.
These are the only true parasites among mammals. Vampires feed exclusively on fresh blood of mammals ( Desmodus rotundus ) and birds ( Diaemus youngi and Diphylla ecaudata ); occasionally attack sleeping people.
The digestive system of vampire bats is adapted for hematophagy - they have a very short esophagus and the stomach has a large intestinal outgrowth.
Usually a bite wound is 5–10 mm long and 1–5 mm deep. A vampire applies the underside of his tongue to a drop of blood that has come out. In this case, the sides of the tongue are wrapped down, creating a tube, as if continuing a deep groove, which runs in the middle of the vampire's lower lip. By slow movements of the tongue forward and backward, a vacuum is reached in the oral cavity, causing the blood to flow upward.
See also
- Vampire bats
- Hirudinosis
- Vampires
Literature
- Balashov Yu. S. Evolution of hematophagy among insects and ticks // Entomol. review - 1999. - T. 78, no. 3. - S. 749–763.
Notes
- ↑ Key to insects of the Russian Far East. T. V. Caddis flies and lepidopterans. Part 4. / under the general. ed. P.A. Lera . - Vladivostok: Dalnauka, 2003 .-- 688 p. - 500 copies. - ISBN 5-8044-0343-5 .
- ↑ Nelson J.S. (2009): Fishes of the World Fauna. Translation of the 4th rev. ed. N. G. Bogutskaya / Preface and explanatory dictionary of N. G. Bogutskaya, A. M. Naseki and A. S. Gerd. M.: Book House LIBROCOM, 880 p.