Hirudo verbana is a species of leech.[2]
| Hirudo verbana | |
|---|---|
| |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Annelida |
| Clade: | Pleistoannelida |
| Clade: | Sedentaria |
| Class: | Clitellata |
| Subclass: | Hirudinea |
| Order: | Arhynchobdellida |
| Family: | Hirudinidae |
| Genus: | Hirudo |
| Species: | H. verbana
|
| Binomial name | |
| Hirudo verbana Carena, 1820
| |
Hirudo verbana has long been used as a medicinal leech under the species H. medicinalis, but has recently been recognized as a separate species distinct from the traditional or European medicinal leech of that name.[2][3]
Anatomy
editThe body of this species is composed of 34 segments. Internally, it has a gut (alimentary canal) with two primary sections, the crop and the intestinum/intestine. The crop consists of a primary canal with lateral ceca extending off from it. The crop connects to the intestinum at around the 19th-20th body segment. Alongside the alimentary canal are 17 pairs of nephridia, as well as bladders.[4]
Feeding
editHirudo verbana feeds on blood (hematophagy). During a blood meal, a leech rhythmically contracts its muscles to draw blood from a host animal into the crop for storage. It can consume over five times its own weight in blood in one feeding. Once satiated, a leech detaches from its host. Hirudo verbana uses anticoagulants when it feeds, so its bite wounds continue bleeding for some time afterwards.[4]
For a few hours after feeding, H. verbana becomes largely inactive. Within its crop, water and some osmolytes are removed from the consumed blood and excreted through a series of nephridia and bladders. As a result, the weight of blood is reduced by nearly half and the remaining erythrocytes (red blood cells) are concentrated.[4]
This leech can go for up to six months in between blood meals. During this time, erythrocytes in the crop are slowly transported to the intestinum to be lysed so their nutrients can be absorbed.[4]
Host animals include mammals, fish, water birds and amphibians. Amphibians such as tadpoles and juvenile hosts are important hosts for juvenile leeches, which cannot pierce mammalian skin for the first two feedings.[5]
Attachment
editLike other leeches, H. verbana has anterior and posterior suckers that allow it to attach to a range of substrates in both air and water. It can even attach to porous, air-permeable substrates. In the wild, this ability may be relevant for attaching to porous rocks or the furry skin of host animals. The properties of leech suckers may be useful in design of biomimetic suction cups.[6]
Genome
editHirudo verbana has a haploid chromosome number of 13, contrasting with the 14 of H. medicinalis and the 12 of H. orientalis.[7]
Microbiome
editThe crop of H. verbana is dominated by two bacterial symbionts: an Aeromonas sp. and a Rikenella-like bacterium. Aeromonas has a low abundance prior to H. verbana's feeding, becomes three orders of magnitude more abundant after feeding and then gradually declines afterwards. The intestinum has a more diverse microbiome, containing (in addition to Aeromonas and Rikenella-like bacteria) Firmicutes, Fusobacteria, Morganella morganii and members of the α, γ, and δ Proteobacteria. These may benefit the leech by providing nutrients which are scarce in blood (e.g. B vitamins) or reducing colonisation of the gut by harmful bacteria.[4]
The nephridia and bladders also have bacterial symbionts.[4]
Gallery
edit-
Comparison with H. medicinalis -
Cocoon
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References
edit- ^ "Appendices | CITES". cites.org. Retrieved 2024-01-17.
- ^ a b "New research by scientists at the American Museum of Natural History shows medicinal leeches misclassified for centuries, are likely three species instead of one". American Museum of Natural History. Retrieved 20 August 2013.
- ^ Roger Highfield (11 April 2007). "Medicinal leeches 'are the wrong kind'". The Daily Telegraph. Retrieved 20 August 2013.
- ^ a b c d e f Nelson, Michael C.; Graf, Joerg (2012-07-14). "Bacterial symbioses of the medicinal leech Hirudo verbana". Gut Microbes. 3 (4): 322–331. doi:10.4161/gmic.20227. ISSN 1949-0976. PMC 3463490. PMID 22572874.
- ^ Elliott, J. Malcolm; Kutschera, Ulrich (2011). "Medicinal Leeches: Historical use, Ecology, Genetics and Conservation". Freshwater Reviews. 4 (1): 21–41. doi:10.1608/FRJ-4.1.417. ISSN 1755-084X. S2CID 49530224.
- ^ Kampowski, Tim; Thiemann, Lara-Louise; Kürner, Lukas; Speck, Thomas; Poppinga, Simon (2020). "Exploring the attachment of the Mediterranean medicinal leech ( Hirudo verbana ) to porous substrates". Journal of the Royal Society Interface. 17 (168): 20200300. doi:10.1098/rsif.2020.0300. ISSN 1742-5689. PMC 7423445. PMID 32673516.
- ^ Utevsky, Serge; Kovalenko, Nataliya; Doroshenko, Karyna; Petrauskienė, Laima; Klymenko, Vyacheslav (2009). "Chromosome numbers for three species of medicinal leeches (Hirudo spp.)". Systematic Parasitology. 74 (2): 95–102. doi:10.1007/s11230-009-9198-2. ISSN 0165-5752. PMID 19731093. S2CID 7947757.