Classification and Checklist of Leeches (Phylum Annelida: Class Clitellata: Order Hirudinida) in North America north of Mexico

Compiled by Mark J. Wetzel 1, Frederic R. Govedich 2, William E. Moser 3, and Donald J. Klemm 4

[ page update: 2020-III-21; 2021-VIII-16, XI-20; 2023-I-01; IV-07; VI-06,07; XI-27; 2024-III-17; mjw]

1 Illinois Natural History Survey, Prairie Research Institute at the University of Illinois Urbana-Champaign, Forbes Natural History Building,
1816 S. Oak Street, Champaign, Illinois 61820 USA. E-Mail: mjwetzel{AT}

2 Department of Biology, Southern Utah University, 341 W University Blvd., Cedar City, UT 84720.  E-Mail: govedich{AT}

3 Smithsonian Institution, National Museum of Natural History, Department of Invertebrate Zoology, Museum Support Center, MRC 534, 4210 Silver Hill Road, Suitland, MD 20746 USA.  E-mail: moserw{AT}

4  [formerly, U.S. Environmental Protection Agency, Cincinnati, Ohio USA; Don passed away on 19 September 2023, in Michigan]

Note:  be sure to manually replace the ‘{AT}’ with the ‘@’ symbol in the email addresses provided above prior to sending your messages. **


Freshwater leeches (segmented worms) are important components of benthic communities in nearly every freshwater ecosystem. They are widely distributed, and some groups are found in great abundance. Several of the hirudinidan groups have been used for monitoring and detecting changes in water quality and physical habitats. The habitat and water quality requirements as well as the pollution tolerances of some species of freshwater leeches have been documented in the literature by a few investigators. Practical taxonomic keys are now available to species, but many benthic water quality assessment studies still do not treat the leeches adequately because the investigators lack taxonomic and systematic expertise, as well as knowledge of and experience in using available keys. The inadequate treatment by some investigators represents a loss of valuable ecological data and information for use in bioassessment of the quality of water resources, water pollution, or other changes in aquatic ecosystems resulting from natural causes or anthropogenic activities of man. We present here a current classification and list of freshwater leeches occurring in North America north of Mexico.

Some of the recent distributional information for leeches in North America was summarized during our affiliation with the American Fisheries Society AFS) Committee on Names of Aquatic Invertebrates (CNAI). The primary objective of the CNAI, established on 30 September 1981 by AFS president John J. Magnuson, was to achieve uniformity and confusion in the vernacular [and scientific] nomenclature of aquatic invertebrates. Under the direction of Dr. Donna Turgeon, a series of volumes in the AFS Special Publications series [SP] focusing on invertebrate groups (by phylum) was initiated, resulting in the publication of several volumes: SP 16 (Mollusks – Turgeon et al. 1988), SP 17 (Decapod Crustaceans – Williams et al. 1989), SP 22 (Cnidaria and Ctenophora – Cairns et al. 1991), SP 26 (Mollusks, Second Edition – Turgeon et al. 1998), SP 28 (Cnidaria and Ctenophora, Second Edition – Cairns et al. 2002), and SP 31 (Crustaceans, Second Edition – McLaughlin et al. 2005). These are available for purchase via this AFS website.  Coates and Wetzel served on this Committee from 1989 through 2005 (as co-chairs of the clitellate Annelid Subcommittee), and (in collaboration with many colleagues, including Don Klemm, Bill Moser, John Reynolds, Steve Fend, R. Deedee Kathman, and Stuart Gelder) had been preparing the non-clitellate Annelida volume for this series. Dr. Kristian Fauchald (Smithsonian Institution, National Museum of Natural History) had been chairing the polychaete annelid subcommittee). Unfortunately, the AFS CNAI committee has been dormant for several years following the retirement of our enthusiastic and tireless CNAI committee chair, Dr. Turgeon; information compiled during our preparation of the Annelida volume has or will be presented in different formats.

We thank our annelidically-aligned colleagues in North America and elsewhere in the world for their contributions to the study of segmented worms, and for providing us with reprints and other information summarizing their research, thus allowing us to remain relatively current with the taxonomy, systematics, and ecology of leeches and other annelid groups; our efforts to maintain and continuously update this checklist is dependent upon collaboration between and corroboration among our fellow aquatic biologists.

The checklist

Currently, three orders, eight families, 19 genera, and 94+ nominal species of leeches are known to occur in North America north of Mexico. We present here a general classification and checklist of these species based upon records published in the peer-reviewed literature. While many additional records of leeches exist—representing specimens identified to the genus and species levels during the completion of a variety of privately and publicly funded projects at the local, state, regional, federal, and provincial government levels—those records remain ‘unavailable’ to science in general because 1) preliminary identifications of specimens have not been verified by recognized leech specialists, and / or 2) these data have not been published in the peer-reviewed literature. The unfortunate reality here is that many of these identified yet unpublished records likely could represent new distributional information for taxa at the drainage, state, provincial, and possibly continental level. Furthermore, many of these records could represent a) new (undescribed) species, b) identified species that are considered rare throughout their known distributional range, c) species for which few mature specimens have been examined, and/or d) new ecological affiliations (e.g., geographical, physical, biological, water quality).

Sources of information for species included in this checklist

The freshwater leech fauna of North America has been documented in several major publications (e.g., Davies 1991; Davies and Govedich 2001; Govedich et al. 2010; Klemm 1985, 1990, 1991, 1995; Sawyer 1972, 1986a,b,c), literature cited therein, and more recent publications (included in the literature cited/references section at the bottom of this website, plus several others to be added herein). Please consult these publications for additional (and usually more specific) distributional information for selected taxa. Citations for newly published and otherwise pertinent publications focusing on leech biology, ecology, distribution, taxonomy, and systematics in North America are added to this website periodically.  

We encourage contact from you with addenda, and errata needing correcting to assure this website remains accurate, and current.  

Classification and checklist of the leeches occurring in North America North of Mexico

– – Phylum Annelida – –

Class Clitellata
Order Hirudinida – sensu Siddall, Apakupakul, Burreson, Coates, Erséus, Gelder, Källersjö & Trapido-Rosenthal, 2001 

Order Acanthobdellida Livanow, 1905

Family Acanthobdellidae Livanow, 1905

Genus Acanthobdella Grube, 1851
     Acanthobdella peledina Grube, 1851

Order Arhynchobdellida R. Blanchard, 1894

Family Haemopidae Sawyer, 1986

Genus Haemopis Savigny, 1822
     Haemopis grandis (Verrill, 1874)
     Haemopis plumbea Moore, 1912
     Haemopis kingi Mathers, 1954
     Haemopis lateromaculata Mathers, 1963  [see Hovingh, 2006]
     Haemopis marmorata (Say, 1824)
     Haemopis ottorum Wirchansky & Shain, 2010
     Haemopis septagon Sawyer & Shelley, 1976
     Haemopis terrestris (Forbes, 1890)

Family Hirudinidae Whitman, 1886

Genus Hirudo Linnaeus, 1758
     Hirudo medicinalis Linnaeus, 1758 – I –

Family Macrobdellidae Richardson, 1969

Genus Macrobdella Verrill, 1872 – see updated information in Phillips Et Al. (2019)
     Macrobdella decora (Say, 1824)
     Macrobdella ditetra Moore, 1953
     Macrobdella diplotertia Meyer, 1975
    Macrobdella mimicus Phillips, Salas-Montiel, Kvist & Oceguera-Figueroa, 2019
          USA: MD (type locality), GA, SC, NC , VA, NY.
     Macrobdella sestertia Whitman, 1886

Genus Philobdella Verrill, 1874
     Philobdella floridana (Verrill, 1874)
     Philobdella gracilis Moore, 1901

Family Erpobdellidae R. Blanchard, 1894

Genus Erpobdella de Blainville, 1818
     Erpobdella [= Dinaanoculata (Moore, 1898)
     Erpobdella [= Mooreobdellabucera Moore, 1949
     Erpobdella [= Dinadubia (Moore & Meyer, 1951)
     Erpobdella [= Mooreobdellafervida (Verrill, 1871)
     Erpobdella lahontana Hovingh & Klemm, 2000
     Erpobdella [= Mooreobdellamelanostoma (Sawyer & Shelley, 1976)
     Erpobdella [= Mooreobdellamicrostoma (Moore, 1901)
     Erpobdella [= Nephelopsisobscura (Verrill, 1872)
     Erpobdella [= Dinaparva (Moore, 1912)
     Erpobdella punctata (Leidy, 1870)
     Erpobdella coastalis Sawyer & Shelley, 1976
     Erpobdella [= Mooreobdellatetragon (Sawyer & Shelley, 1976)

Genus Motobdella Govedich, Blinn, Keim, & Davies, 1998
     Motobdella [= Erpobdellamontezuma (Davies, Singhal, and Blinn, 1985)
     Motobdella sedonensis Govedich, Blinn, Keim, & Davies, 1998

Family Salifidae Johansson, 1910

Genus Barbronia Johansson, 1918
     Barbronia weberi R. Blanchard, 1897 – I – (see Rutter and Klemm, 2001)

Order Rhynchobdellida R. Blanchard, 1894 – see Tessler et al. (2018)

Suborder Glossiphoniiformes Tessler and de Carle, 2018

Family Glossiphoniidae Vaillant, 1890

Genus Actinobdella Moore, 1901
     Actinobdella annectens Moore, 1906
     Actinobdella inequiannulata Moore, 1901

Genus Alboglossiphonia Lukin, 1976
     Alboglossiphonia heteroclita (Linnaeus, 1761)
    Alboglossiphonia pallida (Verrill, 1872) – (see Moser et al. 2022)

Genus Batracobdella Viguier, 1879
     Batracobdella paludosa (Carena, 1824)

Genus Glossiphonia Johnson, 1816
     Glossiphonia complanata (Linnaeus, 1758) 4
Glossiphonia elegans (Verrill, 1872) 4
     Glossiphonia [= Boreobdellaverrucata (Fr. Müller, 1844)

Genus Helobdella R. Blanchard, 1896
     Helobdella austinensis Kutschera, Langguth, Kuo, Weisblat & Shankland, 2013
     Helobdella blinni Beresic-Perrins, Govedich, Banister, Bain, Rose & and Shuster. 2017
     Helobdella bowermani Moser, Fend, Richardson, Hammond, Lazo-Wasem, Govedich, & Gullo, 2013
     Helobdella californica Kutschera, 1988
     Helobdella echoensis Saglam, Kutschera, Saunders, Saidel, Balombini & Shain, 2018 2
     Helobdella [= Gloiobdellaelongata (Castle, 1900)
     Helobdella eriensis Saglam, Kutschera, Saunders, Saidel, Balombini & Shain, 2018 2
     Helobdella fusca (Castle, 1900)
     Helobdella lineata (Verrill, 1874)
     Helobdella modesta (Verrill, 1872)
     Helobdella papillata Moore, 1952 
          [ commonly misidentified as H. triserialis; see footnote ]
     Helobdella robusta Shankland, Bissen & Weisblat, 1992
     Helobdella serendipitous Saglam, Kutschera, Saunders, Saidel, Balombini & Shain, 2018 3
     Helobdella stagnalis (Linnaeus, 1758) 2
     Helobdella transversa Sawyer, 1972

Genus Marvinmeyeria Soos, 1969
     Marvinmeyeria lucida (Moore, 1954)

Genus Placobdella R. Blanchard, 1893
    Placobdella akahkway Fan, Carle & Kvist, 2022 – CAN: Alberta, Saskatchewan, Manitoba
     Placobdella ali Hughes & Siddall, 2007 – see Richardson et al. 2010
     Placobdella appalachiensis Moser & Hopkins, 2014
     Placobdella [= Oligobdellabiannulata (Moore, 1900)
     Placobdella burresonae Siddall & Bowerman, 2006
     Placobdella [= Desserobdellacryptobranchii (Johnson & Klemm, 1977)
          – see Moser et al. 2013
     Placobdella hollensis (Whitman, 1892)
     Placobdella [= Desserobdellamichiganensis (Sawyer, 1972)
     Placobdella kwetlumye Oceguera-Figueroa, Kvist, Watson, Sankar, Overstreet
          & Siddall, 2010 – USA: Whatcom Co., WA; Lake Co., OR; ID
     Placobdella montifera (Moore, 1906)
     Placobdella multilineata Moore, 1953
     Placobdella nuchalis Sawyer & Shelley, 1976
     Placobdella ornata (Verrill, 1872)
     Placobdella papillifera (Verrill, 1872)
     Placobdella parasitica (Say, 1824)
     Placobdella pediculata Hemingway, 1908
     Placobdella [= Desserobdellaphalera (Graf, 1899)
     Placobdella [= Desserobdellapicta (Verrill, 1872) – see Barta and Sawyer (1990)
     Placobdella rugosa (Verrill, 1874) – see Moser et al. 2012 [BPMNH 53, citation below]
     Placobdella siddalli Richardson & Moser, 2017 – USA: Georgia Co., MS
     Placobdella sophieae Oceguera-Figueroa, Kvist, Watson, Sankar, Overstreet & Siddall, 2010
     Placobdella translucens Sawyer & Shelley, 1976

Genus Theromyzon Phillippi, 1867
     Theromyzon bifarium Oosthuizen & Davies, 1993
     Theromyzon maculosum (Rathe, 1862) 5
     Theromyzon rude (Baird, 1863)
     Theromyzon tessulatum (O.F. Müller, 1774) 5
     Theromyzon tigris Foote, Iwama, de Carle & Kvist, 2022 – CAN: AB, SK
     Theromyzon trizonare Davies & Oosthuizen, 1993

Family Piscicolidae Johnston, 1865

Genus Cystobranchus Diesing, 1859
     Cystobranchus [= Gonimosobdellaklemmi (Williams & Burreson, 2005)
     Cystobranchus mammillatus (Malm, 1863)
     Cystobranchus meyeri Hayunga & Grey, 1976
     Cystobranchus salmositicus (Meyer, 1946) [= Piscicola salmositica]
     Cystobranchus verrilli Meyer, 1940
     Cystobranchus virginicus Hoffmann, 1964

Genus Myzobdella Leidy, 1851 [= Illinobdella Meyer, 1940]
     Myzobdella lugubris Leidy, 1851
     Myzobdella [= Piscicolariareducta (Meyer, 1940)

Genus Piscicola de Blainville, 1818
     Piscicola geometra (Linnaeus, 1761)
     Piscicola milneri (Verrill, 1871)
     Piscicola punctata (Verrill, 1871)


– I – = Introduced

1 In previous keys (Klemm 1982, 1985, Sawyer 1986b), specimens would fall under the description of Helobdella triserialis (E. Blanchard, 1849). Based upon the original species descriptions and the results of a phylogenetic analysis, Siddall and Borda (2003) differentiated Helobdella papillata (three irregular rows of papillae irrespective of size and pigmentation) from Helobdella triserialis (cephalic transverse banding). Helobdella papillata—as it is now defined—is common and widely distributed throughout eastern North America. Helobdella triserialis occurs in South America {modified from Moser et al. 2006}.

2 The original description of Helobdella stagnalis by Linnaeus in 1758 was based on common European specimens. The brown, chitinous scute on the dorsal-anterior surface of this taxon observed on specimens elsewhere in the world has generally led to the classification of all scute-bearing members of the genus as H. stagnalis. In their paper, Saglam et al. (2018) presented the morphology and behavior of the type species from Europe and analyze H. stagnalis-like specimens collected worldwide, providing evidence for at least four distinct scute-bearing Helobdella species that can be morphologically resolved.

3 Saglam et al. (2018) inadvertently created nomenclatural issues when writing this paper, spelling the specific epithet for ‘Helobdella serendipitous‘ three different ways in the text  its original description—errors that were not caught by initial reviewers of the manuscript, nor editor(s) of the journal, Zootaxa.   These errors were corrected in a subsequent paper by Saglam et. al. (2019).

4 Mack and Kvist (2019), using cytochrome c oxidase subunit I (COI) sequences from newly collected specimens of Glossiphonia complanata and Glossiphonia elegans from a broad geographic range covering southern Canada, parts of the U.S., Slovenia, and Croatia, confirm that G. complanata is likely confined to Europe. The species is phylogenetically distinct from G. elegans, which seems to exclusively inhabit North America.  Please access their paper for additional information, and their emphasis for future research into the biogeography and population genetics of the genus Glossiphonia.

5 Foote, Iwama, de Carle, and Kvist (2022) discussed the apparent global distribution of Theromyzon tessulatum and Th. maculosum – two species each with type localities in Europe – highlighting the collections of these taxa by Oosthuizen and Davies (1993) in North America considered to be morphologically identical to the European type specimens and thus suggesting conspecificity, and the possibility of as yet undiscovered cryptic diversity. Be sure to consult these two papers. 

Literature Cited and Selected References

Anderson, K.,  G. Braoudakis, and S. Kvist. 2020. Genetic variation, pseudocryptic diversity, and phylogeny of Erpobdella (Annelida: Hirudinida: Erpobdelliformes), with emphasis on Canadian species. Molecular Phylogenetics and Evolution 143: 106688

Barta, J.R., and R.T. Sawyer. 1990. Definition of a new genus of glossiphoniid leech and a redescription of the type species, Clepsine picta Verrill, 1972. Canadian Journal of Zoology 68: 1942–1950.

Beresic-Perrins, R.K., F.R. Govedich, K. Banister, B.A. Bain, D. Rose, and S.M. Shuster. 2017. Helobdella blinni sp. n. (Hirudinida, Glossiphoniidae) a new species inhabiting Montezuma Well, Arizona, USA. ZooKeys 661: 137–155.

Borda, E., and M.E. Siddall. 2004a. Arhynchobdellida (Annelida: Oligochaeta: Hirudinida): phylogenetic relationships and evolution. Molecular Phylogenetics and Evolution, 30: 213–225.

Borda, E., and M.E. Siddall. 2004b. Review of the evolution of life history strategies and and phylogeny of the Hirudinida (Annelida: Oligochaeta). Lauterbornia, 52: 5–25.

Burreson, E.M., and D.W. Williams. 2005. Resdescription of Cystobranchus virginicus Hoffman, 1964, and Cystobranchus salmositicus (Meyer, 1946) (Hirudinida: Piscicolidae) from freshwater fishes in North America. Comparative Parasitology 72(2): 157–165.

de Carle, D., A. Oceguera-Figueroa, M. Tessler, M.E. Siddall, and S. Kvist. 2017.  Phylogenetic analysis of Placobdella (Hirudinea: Rhynchobdellida: Glossiphoniidae) with consideration of COI variation. Molecular Phylogenetics and Evolution 114: 234–248.

Davies, R.W., R.N. Singhal, and D.W. Blinn. 1985. Erpobdella montezuma (Hirudinoidea: Erpobdellidae), a new species of freshwater leech from North America. Canadian Journal of Zoology 63: 965–969.

Davies, R.W. 1991. Annelida: Leeches, Polychaetes, and Acanthobdellids. Pp. 437-479, In: James H. Thorp and Alan P. Covich (eds.). Ecology and classification of North American freshwater invertebrates. Academic Press, NY.

Davies, R.W., and F.R. Govedich. 2001. Chapter 13. Annelida: Euhirudinea and Acanthobdellidae. Pp. 465–504, In: James H. Thorp and Alan P. Covich (eds.). Ecology and Classification of North American freshwater invertebrates. Second Edition. Academic Press, NY. [superseded by Govedich et al. 2010, citation below].

Davies, R.W., F.R. Govedich, and W.E. Moser. 2008. Leech Parasites of Birds. Pp. 501–514, In: Parasitic Diseases of Wild Birds. C.T. Atkinsen, N.J. Thomas, and D.B. Hunter (eds). Wiley-Blackwell.

Davies, R.W., and J.H. Oosthuizen. 1993. A new species of duck leech from North America formerly confused with Theromyzon rude (Rhynchobdellida: Glossiphoniidae). Canadian Journal of Zoology 71: 770–775.

Fan, S.L., D. De Carle, and S. Kvist. 2022. Placobdella akahkway n. sp. (Clitellata: Hirudinea: Glossiphoniidae), a new leech species from central Canada. Zootaxa 5159(2): 265–280.

Foote, M., R. Iwama, D. de Carle, and S. Kvist. 2022. An integrative taxonomic study of the genus Theromyzon (Hirudinea: Glossiphoniidae), with description of a new North American species. Invertebrate Systematics 36(7): 631–646. 

Govedich, F.R., D. Blinn, P. Keim, and R.W. Davies. 1998. Phylogenetic relationships of three genera of Erpobdellidae (Hirudinoidea), with a description of a new genus, Motobdella, and species, Motobdella sedonensis. Canadian Journal of Zoology 76: 2164–2171.

Govedich, F.R., B.A. Bain, W.E. Moser, S.R. Gelder, R.W. Davies, and R.O. Brinkhurst. 2010. Annelida (Clitellata) Oligochaeta, Branchiobdellida, Hirudinida, and Acanthobdellida. Pages 385-436, In: J.H. Thorp and A.P. Covich (eds). Ecology and classification of North American freshwater invertebrates. Third Edition xiv + 1,021 pp. Academic Press / Elsevier, San Diego, CA. ISBN 978-0-12-374855-3. [] USD$ 139.95 / 93.95 Euro.

Hovingh, P. 1993. Zoogeography and paleozoology of leeches, molluscs, and amphibians in western Bonneville Basin. Journal of Paleolimnology 9: 41–54.

Hovingh, P. 2004. Erpobdella (Dinaparva complex (Annelida: Hirudinea: Arhynchobdellida: Erpobdellidae): additional description ofErpobdella parva, E. dubia, and E. lahontana and taxonomic revision. Hydrobiologia 517: 89–105.

Hovingh, P. 2006. The Leech Haemopis lateromaculata (Hirudinea: Haemopidae): Its North America Distribution and Additional Notes on Species Description.  Canadian Field-Naturalist 120(4): 443–451.

Hovingh, P., and D.J. Klemm. 2000. Erpobdella lahontana (Annelida: Hirudinea: Arhynchobdellida: Erpobdellidae), a new species of freshwater leech from North America. Proceedings of the Biological Society of Washington 113(1): 155–161.

Hovingh, P., W.H. Clark, and J. Keebaugh. 2008. Leeches of the Snake River in Idaho and Oregon: paleodrainage implications ofMooreobdella microstoma. Western North American Naturalist 68(2): 210–224.

Hughes, J.L., and M.E. Siddall. 2007. A new species of leech from the New York metropolitan area. American Museum Novitates 3578: 1–6.

Klemm, D.J. 1972. The leeches (Annelida: Hirudinea) of Michigan. Michigan Academician 4(4): 405–444.

Klemm, D.J. 1977. A review of the leeches (Annelida: Hirudinea) in the Great Lakes region. Michigan Academician 9(4): 397–418.

Klemm, D.J. 1982. Leeches (Annelida: Hirudinea) of North America. Environmental Monitoring and Support Laboratory, U.S. Environmental Protection Agency, Cincinnati, OH 45268. EPA-600/3-82-025. 177 pp.

Klemm, D.J. 1985. Freshwater leeches. Pp. 70–173, In: D.J. Klemm (ed.). A guide to the freshwater Annelida (Polychaeta, Naidid and Tubificid Oligochaeta, and Hirudinea) of North America. Kendall/Hunt Publ. Co., Dubuque, Iowa.

Klemm, D.J. 1990. Hirudinea. Pp. 398–415, In: B.L. Peckarsky, P.R. Fraissinet, M.A. Penton, and D.J. Conklin, Jr. (eds.). Freshwater macroinvertebrates of northeastern North America. Cornell University Press, Ithaca, NY.

Klemm, D.J. 1991. Taxonomy and pollution ecology of the great Lakes Region leeches (Annelida: Hirudinea). Michigan Academician 24: 37–103.

Klemm, D.J. 1995. Identification guide to the freshwater leeches (Annelida: Hirudinea) of Florida and other southern states. Bureau of Surface Water Management, Florida Department of Environmental Protection, 2600 Blair Stone Road, Tallahassee, FL 32399. v + 82 pp. [This manual is available free, as a pdf document you can download from the Florida Department of Environmental Protection – Bureau of Laboratories List of Keys and Guides website; you must scroll down to the listing for this manual, then click on the entry ”Leeches.pdf” to begin the download; this file is 3.1 MB in size, so will be a very slow download if you are using a dial-up internet connection].

Klemm, D.J., B.A. Daniels, W.E. Moser, and R.J.G. Lester. 2003. Biology of the leech Actinobdella inequiannulata Moore, 1901 (Annelida: Hirudinea: Rhynchobdellida: Glossiphoniidae), parasitic on the white sucker, Catostomus commersoni Lacepède, 1803, and the longnose sucker, Catostomus catostomus Forster, 1773, in Algonquin Provincial Park, Ontario, Canada. Comparative Parasitology 70: 120–127.

Klemm, D.J., D.G. Huggins, and M.J. Wetzel. 1979. Kansas leeches (Annelida: Hirudinea) with notes on distribution and ecology. Technical Publications of the State Biological Survey of Kansas 8: 38–46.

Klemm, D.J., P.A. Lewis, F. Fulk, and J.M. Lazorchak. 1990. Macroinvertebrate field and laboratory methods for evaluating the biological integrity of surface waters. EPA/600/4-90/030. Environmental Monitoring systems Laboratory, U.S. Environmental Protection Agency, Cincinnati, OH 45268.

Kutschera, U. 1988. A new leech species from North America, Helobdella californica nov. sp. (Hirudinea: Glossiphoniidae). Zoologischer Anzeiger 220: 173–178.

Kutschera, U. 2011. The Golden Gate Leech Helobdella californica (Hirudinea: Glossiphoniidae): Occurrence and DNA-based taxonomy of a species restricted to San Francisco. International Review of Hydrobiology 96(3): 286–295.

Kutschera, U., H. Langguth, D.-H. Kuo, D.A. Weisblat, and M. Shankland. 2013. Description of a new leech species from North America, Helobdella austinensis n. sp. (Hirudinea: Glossiphoniidae), with observations on its feeding behaviour. Zoosyst. Evol. 89(2): 239–246.

Light, J.E., and M.E. Siddall. 1999. Phylogeny of the leech family Glossiphoniidae based on mitochondrial gene sequences and morphological data. Journal of Parasitology, 85: 815–823.

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Magalhães, W.F.,  P. Hutchings, A. Oceguera-Figueroa, P. Martin, R.M. Schmelz, M.J. Wetzel, H. Wiklund,  N.J. Maciolek, G.Y. Kawauchi, and J.D. Williams. 2021. Segmented worms (Phylum Annelida): a celebration of twenty years of progress through Zootaxa and call for action on the taxonomic work that remains. Zootaxa 4979(1): 190–211.

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Moser, W.E., S.V. Fend, D.J. Richardson, C.A. Hammond, E.A. Lazo-Wasem, F.R. Govedich, and B.S. Gullo. 2013. A new species of Helobdella (Hirudinida: Glossiphoniidae) from Oregon, USA. Zootaxa 3718(3): 287–294.

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Moser, W.E., D.J. Richardson, C.I. Hammond, and E. Lazo-Wasem. 2011. Molecular characterization of Helobdella modesta (Verrill, 1872) (Hirudinida: Glossiphoniidae) from its type locality, West River and Whitneyville Lake, New Haven County, Connecticut, USA. Zootaxa 2834: 65–68.

Moser, W.E., D.J. Richardson, C.I. Hammond, F.R. Govedich, & E. Lazo-Wasem. 2012. Resurrection and redescription of Placobdella rugosa (Verrill, 1874) (Hirudinida: Glossiphoniidae). Bulletin of the Peabody Museum of Natural History 53 (2): 375–381.

Moser, W.E., D.J. Richardson, C.I. Hammond, and E. Lazo-Wasem. 2012. Molecular characterization of Glossiphonia elegans (Verrill, 1872) (Glossiphoniidae: Hirudinida) from its type locality, West River, New Haven County, Connecticut, USA. Zootaxa 3195: 57–60.

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Moser, W.E., D.J. Richardson, B.A. Wheeler, K.J. Irwin, B.A. Daniels, S.E. Trauth, and D.J. Klemm. 2008. Placobdella cryptobranchii (Rhynchobdellida: Glossiphoniidae) on Cryptobranchus alleganiensis bishopi (Ozark Hellbender) in Arkansas and Missouri. Comparative Parasitology 75(1): 98–101.

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Suggested citation for this electronic webpage:

Wetzel, M.J., F.R. Govedich, W.E. Moser, and D.J. Klemm.  2024.  Classification and Checklist of the Leeches (Phylum Annelida: Class Clitellata: Subclass Hirudinida) occurring in North America north of Mexico. March. 
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