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1.
Mol Biol Rep ; 50(8): 6753-6767, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37389700

RESUMO

BACKGROUND: Herein, we describe a new species of turtle blood-feeding leech, Placobdella nabeulensis sp. nov. from Palearctic North Africa (Tunisia and Algeria). The new species is described based on detailed morphological analyses using light and scanning electron microscopes. RESULTS: Apart from the detailed morphology of the atrium, morphological features alone do not sufficiently separate the species from congeners due to the absence of distinct diagnostic characters. Therefore, we turned to molecular data to better distinguish this new species from other members of the genus and establish a basis for its genetic separation. Four DNA fragments were successfully amplified, including mitochondrial COI and 12S rDNA, as well as nuclear 28S rDNA and histone H3. We then provided the molecular descriptor of the taxon, based on redundant diagnostic nucleotide combinations in DNA sequence alignment within the Folmer region. Results of the phylogenetic analysis and species delimitation methods (ABGD, ASAP, and bPTP) based on the COI locus support the species rank of the Tunisian-Algerian Placobdella. CONCLUSIONS: The new species is most closely related to the European species Placobdella costata (Fr. Müller, 1846) and the present study indicates that Placobdella nabeulensis sp. nov. has likely been confused with the European counterpart in several previous studies. This article is registered at www.zoobank.org under urn:lsid:zoobank.org:pub:4A4B9C1D-2556-430F-8E4B-0CE99F2012F5.


Assuntos
Sanguessugas , Animais , Sanguessugas/genética , Sanguessugas/anatomia & histologia , Filogenia , DNA Ribossômico , Argélia , Tunísia
2.
Biology (Basel) ; 10(4)2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33918739

RESUMO

Until the beginning of the 21st century, the famous medicinal leech was thought to be represented by only one species, Hirudo medicinalis. However, recent publications have demonstrated that under that name, at least five different species of medicinal leeches were hidden. During the last decade, the biogeography of Western-Palaearctic leeches has begun to unravel, untangling their diversity in practically all of Europe, except for its westernmost peninsula, Iberia. Hirudo medicinalis has been repeatedly reported from Iberia, but those records were considered questionable. We discovered H. verbana in northern Spain, constituting its first record in Iberia. Using an integrative approach (combining morpho-anatomical data and molecular analyses using three genes, COI,12S rRNA, and ITS2), two endemic and geographically separated Iberian lineages have been found. One of them is easily distinguished by its distinctive colour-pattern and is described as H. verbana bilineata ssp. nov. We characterized the new subspecies morphologically, ecologically, and genetically. We also established its phylogenetic relationships with other European Hirudo spp. and confirm the presence of H. troctina in Iberia, occurring as far as 43° lat. N. Iberian H. verbana records constitute its westernmost known distribution to date. The provided distribution pattern of H. verbana contributes to a better understanding of the complexity of Iberia as a glacial refugium/cradle for endemisms, harbouring populations with a high degree of genetic structure that began to settle throughout the Pleistocene. Iberian Hirudo populations are declining in recent decades and there is an urgent need to assess their conservation status and to initiate conservation measures to reverse their decline.

3.
Syst Parasitol ; 95(8-9): 849-861, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30141118

RESUMO

A new fish leech Ambulobdella shandikovi n. g., n. sp. (Hirudinida: Piscicolidae), a parasite of Whitson's grenadier Macrourus whitsoni (Regan) (Macrouridae: Gadiformes) collected in the Ross Sea at depths from 1,221 to 1,433 m, is described and compared with related taxa based on morphological and molecular characters. Ambulobdella shandikovi n. sp. is characterised by prominent segmental tubercles on the venter and dorsal segmental tubercles, an uncommon appearance of its anterior sucker with ear-like edges and an inner membrane around the mouth-pore, well-developed musculature and a unique combination of features of the reproductive and digestive systems. The presence of uncommon tubercles can be attributed, in part, to temporary associations of A. shandikovi n. sp. with its fish hosts and a need for well-developed sensory and locomotory organs. A certain locomotory function of ventrolateral tubercles of A. shandikovi n. sp. is hypothesised and discussed. Further deep-sea surveys are obviously needed to shed light on the behaviour and mode of locomotion of this species.


Assuntos
Gadiformes/parasitologia , Sanguessugas/anatomia & histologia , Sanguessugas/classificação , Filogenia , Animais , Regiões Antárticas , Especificidade da Espécie
4.
Mol Phylogenet Evol ; 121: 52-60, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29277454

RESUMO

Phylogenetic relationships between species of the genus Hirudo plus genetic variation in the entire distribution range of Hirudo orientalis were investigated based on mitochondrial (COI and 12S rDNA) and nuclear (ITS1+5.8S+ITS2) genome regions. The sister relationship of Hirudo orientalis and H. medicinalis was revealed with a high posterior probability. A broad and patchy distribution with minor genetic differences was observed in populations of H. orientalis along the central and Middle Eastern parts of Asia. The known distribution range occurred in topographically heterogeneous landscapes around the Caspian Sea. The demographic analysis suggests the selection of the COI locus under unfavourable respiratory conditions, but population size expansion cannot be fully rejected. The genetic variation trend indicated northward dispersal. Higher haplotype diversity in the South Caspian region potentially suggests the area as a historical refugium for the species. The vast dispersal is assumed to occur after the Pleistocene glaciations via vertebrate hosts.


Assuntos
Anelídeos/classificação , Anelídeos/genética , Genética Populacional , Filogenia , Migração Animal , Animais , Sequência de Bases , Teorema de Bayes , DNA Mitocondrial/genética , Variação Genética , Geografia , Haplótipos/genética , Oriente Médio
5.
Syst Parasitol ; 84(1): 71-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23263942

RESUMO

Acanthobdellidans are unique in their organisation and phylogenetic relationships due to having transitional characters that combine features of oligochaetous and achaetous annelids. Alongside the relatively well-studied Acanthobdella peledina Grube, 1851, there is another member of the group, Paracanthobdella livanowi (Epshtein, 1966), with five rows of chaetae and an anterior sucker. It appears that the anterior sucker is weakly developed in small juveniles but acquires a deep cavity in adults. Smaller individuals of P. livanowi can be distinguished from A. peledina, which does not possess an anterior sucker, by the varying breadth of their chaetae. The mid-body segment consists of two doubled annuli in juveniles and is quadri-annulate in large individuals. In Kamchatka freshwaters, hosts of P. livanowi mostly include Salvelinus spp. and more rarely Gasterosteus aculeatus, Oncorhynchus mykiss and O. kisutch. New information on the distribution and the biology of P. livanowi is presented.


Assuntos
Anelídeos/classificação , Animais , Anelídeos/anatomia & histologia , Federação Russa , Truta/parasitologia
6.
Mol Phylogenet Evol ; 63(2): 475-85, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22342869

RESUMO

Medicinal leeches (Hirudo spp.) are among the best-studied invertebrates in many aspects of their biology. Yet, relatively little is known about their biogeography, ecology and evolution. Previous studies found vast ranges but suggested low genetic diversity for some species. To examine this apparent contradiction, the phylogeny and phylogeography of the widespread Hirudo verbana, Hirudo medicinalis and Hirudo orientalis were investigated in a comparative manner. Populations from across their ranges in Europe, Asia Minor, the Caucasus and Central Asia, were analyzed by various phylogenetic and population genetic approaches using both mitochondrial (COI and 12S) and nuclear DNA sequences (ITS1, 5.8S and ITS2). The populations showed surprisingly little genetic differentiation despite vast ranges. The only clear structure was observed in H. verbana. This species is subdivided into an Eastern (southern Ukraine, North Caucasus, Turkey and Uzbekistan) and a Western phylogroup (Balkans and Italy). The two phylogroups do not overlap, suggesting distinct postglacial colonization from separate refugia. Leeches supplied by commercial facilities belong to the Eastern phylogroup of H. verbana; they originate from Turkey and the Krasnodar Territory in Russia, two leading areas of leech export. H. verbana and H. medicinalis have experienced recent rapid population growth and range expansion, while isolation by distance has shaped the genetic setup of H. orientalis. The habitat of the latter is patchy and scattered about inhospitable arid and alpine areas of Central Asia and Transcaucasia. Centuries of leech collecting and transport across Europe seem not to have affected the natural distribution of genetic diversity, as the observed patterns can be explained by a combination of historical factors and present day climatic influences.


Assuntos
Hirudo medicinalis/classificação , Hirudo medicinalis/genética , Filogenia , Filogeografia , Animais , Sequência de Bases , Evolução Biológica , DNA Intergênico/genética , DNA Mitocondrial/genética , DNA Ribossômico/genética , Deriva Genética , Variação Genética , Genética Populacional , Dados de Sequência Molecular , RNA Ribossômico/genética , Análise de Sequência de DNA
7.
Syst Parasitol ; 74(2): 95-102, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19731093

RESUMO

Karyological preparations were made from the testisacs of three medicinal leech species Hirudo medicinalis Linnaeus, 1758, H. verbana Carena, 1820 and H. orientalis Utevsky & Trontelj, 2005 . The samples originated from different populations in Azerbaijan, Kazakhstan, Russian Federation, Ukraine and Uzbekistan. The chromosome numbers were determined both from mitotic and meiotic stages of spermatogenesis using the propionic haematoxylin staining technique. All three species were found to have different haploid chromosome numbers: H. medicinalis 14, H. verbana 13 and H. orientalis 12, thus corroborating the validity of these taxa. The chromosomes can be classified as meta-, submetacentric and acrocentric. The chromosome numbers obtained are similar to that of the related species Haemopis sanguisuga (Linnaeus, 1758), which has 13 pairs.


Assuntos
Cromossomos , Sanguessugas/genética , Animais , Azerbaijão , Cariotipagem , Cazaquistão , Sanguessugas/fisiologia , Meiose , Mitose , Federação Russa , Espermatogênese , Ucrânia , Uzbequistão
8.
Proc Biol Sci ; 274(1617): 1481-7, 2007 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-17426015

RESUMO

The European medicinal leech is one of vanishingly few animal species with direct application in modern medicine. In addition to the therapeutic potential held by many protease inhibitors purified from leech saliva, and notwithstanding the historical association with quackery, Hirudo medicinalis has been approved by the United States Food and Drug Administration as a prescription medical device. Accurate annotation of bioactive compounds relies on precise species determination. Interpretations of developmental and neurophysiological characteristics also presuppose uniformity within a model species used in laboratory settings. Here, we show, with mitochondrial sequences and nuclear microsatellites, that there are at least three species of European medicinal leech, and that leeches marketed as H. medicinalis are actually Hirudo verbana. Beyond the obvious need for reconsideration of decades of biomedical research on this widely used model organism, these findings impact regulatory statutes and raise concerns for the conservation status of European medicinal leeches.


Assuntos
Alelos , Comércio , Sanguessugas/classificação , Sanguessugas/genética , Filogenia , Análise de Variância , Animais , Sequência de Bases , Primers do DNA , DNA Mitocondrial/genética , Europa (Continente) , Repetições de Microssatélites/genética , Modelos Genéticos , Dados de Sequência Molecular , Análise de Sequência de DNA , Especificidade da Espécie
9.
Parasitol Res ; 98(1): 61-6, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16261357

RESUMO

A recent molecular phylogenetic study has suggested that the genus Hirudo contains a neglected species previously known as the orientalis coloration type of the medicinal leech Hirudo medicinalis. In this paper, the new species is formally described as Hirudo orientalis sp. n. It can most readily be identified by the grass green coloration of the dorsum, segmentally arranged pairs of black quadrangular or rounded dots on its paramarginal dorsal stripes and similarly arranged, but less regular light-colored markings on the predominantly black venter. It has medium-sized epididymes and an evenly coiled vagina. H. orientalis is known from Transcaucasia, Iran, and Uzbekistan. It is widely used in medicine as the "medicinal leech." Very little is known about its exact distribution, specific habitat, and conservation status. The paper contains an identification key to all species of the genus Hirudo.


Assuntos
Hirudo medicinalis/classificação , Hirudo medicinalis/genética , Sanguessugas/classificação , Sanguessugas/genética , Animais , Cromossomos/genética , DNA Mitocondrial/genética , Hirudo medicinalis/anatomia & histologia , Irã (Geográfico) , Sanguessugas/anatomia & histologia , Filogenia , Pigmentação , Homologia de Sequência , Uzbequistão
10.
Mol Phylogenet Evol ; 34(3): 616-24, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15683933

RESUMO

The medicinal leech is the most famous representative of the Hirudinea. It is one of few invertebrates widely used in medicine and as a scientific model object. It has recently been given considerable conservation effort. Despite all attention there is confusion regarding the taxonomic status of different morphological forms, with many different species described in the past, but only two generally accepted at present. The results of the phylogenetic analysis of a nuclear (ITS2+5.8S rRNA) and two mitochondrial gene sequences (12S rRNA, COI) suggest that the genus Hirudo is monophyletic. It consists, apart form the type Hirudo medicinalis and the East Asian Hirudo nipponia, of three other, neglected species. All of them have already been described either as species or morphological variety, and can readily be identified by their coloration pattern. The type species is in weakly supported sister relation with Hirudo sp. n. (described as variety orientalis) from Transcaucasia and Iran. Sister to them stands Hirudo verbana from southeastern Europe and Turkey, which is nowadays predominantly bred in leech farms and used as 'medicinal leech.' The North African Hirudo troctina is the sister taxon to this group of Western Eurasian species, whereas the basal split is between H. nipponia and the Western Palaearctic clade.


Assuntos
Hirudo medicinalis/classificação , Hirudo medicinalis/genética , Animais , Teorema de Bayes , Núcleo Celular/genética , Funções Verossimilhança , Mitocôndrias/genética , Filogenia , RNA Ribossômico
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