Tyrant obdella rex
| Tyrant obdella rex | ||||||||||||
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(A) Jaw of T. rex (B) Anterior suction cup (C) The large teeth of T. rex (D) Teeth of the leech species Limnatis paluda |
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Tyrant obdella | ||||||||||||
| Phillips et al. , 2010 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Tyrant obdella rex | ||||||||||||
| Phillips et al., 2010 |
Tyrannobdella rex is a parasitic leech species that wasdiscoveredin Peru in 1997 andattacksthe mucous membranes of mammals . A more detailed examination and taxonomic classification of the species took place in 2010.
features
In contrast to other species of leeches, Tyrannobdella rex has only one jaw with a single row of teeth (monostichodont). But it has eight teeth, which are relatively large for leeches and up to 0.13 millimeters in length, which is why it bears a name based on the dinosaur Tyrannosaurus rex . These teeth, of which only six can often be seen in a simple light microscope because the other two are subcutaneous , are around five times as long as those of the related genus Limnatis . The closely related leech Pintobdella chiapasensis also has a reduced number of teeth, namely only six per jaw, but is equipped with three jaws.
Lifestyle and diet
In the juvenile stage with a body size of a few millimeters, the leech bites into the mucous membrane and feeds on the host's blood . In contrast to other leeches, Tyrannobdella rex does not fall off after the blood meal, but remains at the bite site for a few days to weeks. After a while it can reach a size of up to 7 cm.
Tyrannobdella rex prefers the mucous membranes of the mouth and nose of humans. Other leeches, which also settle on mucous membranes, have also been found in the nasal cavity, but also in the area of the eyes and the urogenital tract of mammals.
Symptoms
If tyrannous obdella rex invades the nasal cavity , it can cause a severe headache . Because of its small size, the leech is usually not noticed at first. An animal reportedly stayed in its host for several weeks before it was noticed and removed.
Systematics
The characteristic that there is only a single jaw in this species has led to the establishment of its own genus Tyrannobdella , from which only Tyrannobdella rex is known so far . Genera with only one species are called monotypical. The discovery of Tyrannobdella rex and the molecular genetic comparison of its genome with that of other leeches that parasitize on the mucous membranes of mammals have brought new insights into the systematics. It was placed in the Praobdellidae family , which also includes the genera Praobdella , Pintobdella , Myxobdella , Dinobdella , Limnatis and Limnobdella . Most of these genera are native to Africa and Asia, Tyrannobdella rex is the only member of the family from South America, its closest relative, Pintobdella chiapasensis, comes from Mexico , where it parasitizes mainly on the nasal mucous membranes of tapirs . The sister group to the Praobdellidae family are the two purely South American families Semiscolescidae (genera Semiscolex and Patagoniobdella ) and Macrobdellidae (genera Macrobdella , Philobdella and Oxyptychus ).
literature
- Anna J. Phillips, Renzo Arauco-Brown, Alejandro Oceguera-Figueroa, Gloria P. Gomez, María Beltrán, Yi-Te Rai and Mark Siddall: Tyrannobdella rex N. Gen. N. Sp. And the Evolutionary Origins of Mucosal Leech Infestations . PLoS ONE 5, 4, e10057, 2010. doi : 10.1371 / journal.pone.0010057 .
