Aquatic Insects of Michigan

by Ethan Bright, Museum of Zoology Insect Division and School of Natural Resources and Environment
University of Michigan
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Hydrophiloidea (Water Scavenger Beetles) of Michigan

Introduction

Previously considered in one very large group, work since the 1990s using morphological characters of multiple life stages as well as molecular data (e.g., Hansen 1991, 1995, Archangelsky 1998 etc.) , have supported the elevation of 6 former subfamilies to family level (over 3300 species in about 176 genera). Three of these families - Helophoridae, Hydrochidae and Hydrophilidae - occur in Michigan and our region.

Genera are donoted in bold green; species denoted in bold blue have been recorded in Michigan; other species denoted in bold are likely to occur based on their known distribution. You can use the Find function in your web browser to locate families, genera, and species. Synonomous species (indented) are listed below the current valid species (denoted in bold) with its taxonomic status indicated.

HELOPHORIDAE Leach, 1815 (Grooved Water Scavenger Beetles)

This group, previously included in the Hydrophilidae, is principally an aquatic group but with semiaquatic and terrestrial members. They are a mostly Palaearctic group, but with about 50 species in the Nearctic and 12 recorded from Michigan, with another 5 likely to be found based on regional occurrance. Parthenogenesis has been documented in a few species, including H. orientalis (Angus 1970b, Angus and Jie 2020).
    Helophorus Fabricius, 1775: 66 (Subfamily Helophorinae)

      Helophorus (Rhopalelophorus) angusticollis d'Orchymont, 1945: 21 - Downie and Arnett 1996; see also Smetana 1988: 31, 43-44
      Helophorus (Rhopalelophorus) furius Smetana, 1987: 262 - ON, WI (northern: Smetana 1988: 27-28)
        (syn.) Helophorus frater Smetana, 1985: 40 (nec d'Orchymont, 1926)
      Helophorus (Helophorus) grandis (Illiger, 1798: 272 as Elophorus) - record from Huron Co.; see Smetana 1988: 20-21 (introduced species from Europe)
        (syn.) Helophorus aquaticus, Darlington 1927, Brown 1940 (nec Linné 1758)
      Helophorus (Rhopalelophorus) inflectus (McCorkle, 1965: 31 as Elophorus) - Smetana 1988: 25-26; Downie and Arnett 1996
      Helophorus (Rhopalelophorus) lacustris LeConte, 1850: 217 - Downie and Arnett 1996; see also Smetana 1988: 39-40
      Helophorus (Rhopalelophorus) latipenis - WI (syn. or ssp.?)
      Helophorus (Rhopalelophorus) linearis LeConte, 1850: 356 - IL, IN (Waltz 2002: 178), OH, ON, WI (Smetana 1988: 36-37)
        (syn.) Helophorus pallens Casey, 1884: 81
        (syn.) Helophorus oblitus Sharp, 1915: 276
      Helophorus (Rhopalelophorus) lineatus Say, 1823: 200 - Downie and Arnett 1996; see also Smetana 1988: 29-30
        (syn.) Helophorus ventralis Motschulsky, 1860: 105
        (syn.) Helophorus obsoletesulcatus Motschulsky, 1860: 106
      Helophorus (Rhopalelophorus) marginicollis Smetana, 1985: 106 - Smetana 1988: 44; Downie and Arnett 1996
      Helophorus (Rhopalelophorus) nitiduloides d'Orchymont, 1945: 22 - Downie and Arnett 1996; see also Smetana 1988: 37-38
      Helophorus (Rhopalelophorus) nitidulus LeConte, 1855: 357 - Smetana 1988: 28-29; Downie and Arnett 1996
        (syn.) Helophorus gregalis d'Orchymont, 1945: 17
      Helophorus (Rhopalelophorus) oblongus LeConte, 1850: 217 - Downie and Arnett 1996; see also Smetana 1988: 24-25
      Helophorus (Rhopalelophorus) orchymonti Smetana, 1985: 102 - ON, WI (Smetana 1988: 43)
      Helophorus (Rhopalelophorus) orientalis Motschulsky, 1860: 106 - Downie and Arnett 1996; see also Smetana 1988: 34-35
        (syn.) Helophorus brevipalpis, McCorkle, 1965: 26 (nec Bedel, 1881)
      Helophorus (Rhopalelophorus) sempervarians Angus 1970a: 273 - Downie and Arnett 1996; see also Smetana 1988: 32-33
        (syn.) Elophorus jacutus, McCorkle, 1965: 26 (nec Poppius, 1907)
        (syn.) Helophorus jacutus, d'Orchymont, 1945 :9 (nec Poppius, 1907)
      Helophorus (Rhopalelophorus) smetanai Hilsenhoff, 1995 - WI (Hilsenhoff 1995)
      Helophorus (Cyphelophorus) tuberculatus (Gyllenhal, 1808: 129 as Elophorus) - Downie and Arnett 1996; see also Smetana 1988: 45-46, probably periaquatic, associated with Sphagnum
        (syn.) Helophorus scaber LeConte, 1850: 218

    References - Taxonomic and Distribution - Helophoridae

      Angus RB. 1970a. Revisional studies on east Palaearctic and some Nearctic species Helophorus F. (Coleoptera: Hydrophilidae). Ergebnisse der zoologischen Forschungen von Dr. Z. Kaszab in der Mongolei (No. 226). Acta Zoologica Academiae Scientiarum Hungaricae 16: 249-290.
      Angus RB. 1970b. Helophorus orientalis (coleoptera: Hydrophilidae), a parthenogenetic water beetle from Siberia and North America, and a British pleistocene fossil. The Canadian Entomologist 102(2): 129-143.
      Angus RB, Jia Fenglong. 2020. Triploidy in Chinese parthenogenetic Helophorus orientalis Motschulsky, 1860, further data on parthenogenetic H. brevipalpis Bedel, 1881 and a brief discussion of parthenogenesis in Hydrophiloidea (Coleoptera). CompCytogen 14(1): 1–10
      Brown WJ. 1940. Notes on the American distribution of some species of Coleoptera common to the European and North American continents. The Canadian Entomologist 72: 65–78.
      Casey T. 1884. Contributions to the desciptive and systematic coleopterology of North America. Part I. Transactions of the American Philosophical Society: 1-60. VIEW
      Darlington PJ. 1927. Helophorus aquaticus L. in America. Psyche 34(5): 174-175. VIEW
      Downie NM, Arnett RH, Jr. 1996. The beetles of northeastern North America. Vol. 1. The Sandhill Crane Press, Gainesville, Florida. 880 pp.
      Fabricius JC. 1775. Systema entomologiae : sistens insectorvm classes, ordines, genera, species, adiectis synonymis, locis, descriptionibvs, observationibvs. Flensbvrgi et Lipsiae: In Officina Libraria Kortii. 832 p. VIEW.
      Gyllenhal L. 1808. Insecta Suecica descripta. Classis I. Coleoptera sive Eleutherata. Scaris: Leverentz Vol. 1, xii, 752 pp.
      Hilsenhoff WL. 1995. Aquatic Hydrophilidae and Hydraenidae of Wisconsin (Coleoptera). I. Introduction, key to genera, and distribution, habitat, life cycle and identification of species of Helophorus Fabricius, Hydrochus Leach, and Berosus Leach (Hydrophilidae), and Hydraenidae. The Great Lakes Entomologist 28(1):25-53. VIEW.
      Illiger JKW. 1798. Verzeichniss der Käfer Preussens. Entworfen von Johann Gottlieb Kugelann Apotheker in Osterode. 510 pp. Gebauer, Halle.
      Leach WE. 1815. Entomology, pp. 57-172 in Edinburgh Encyclopedia, Volume 9(1)(Brewster, ed.). Edinburgh. (VIEW)
      LeConte JL. 1850. General remarks upon the Coleoptera of Lake Superior. In Agassiz, Lake Superior. Vol. IV. Boston, p. 201-242.
      d'Orchymont A. 1926. Contribution à l'étude des Hydrophilides VI. Bulletin du Musée Royal d’Histoire Naturelle de Belgique 66: 201-248.
      d'Orchymont A. 1945. Notes sur des Helophoras, spécialement Américains (Coleoptera Palpicomia Hydrophilidae). Bulletin du Musée Royal d’Histoire Naturelle de Belgique 21(8): 1-28.
      McCorkle DV. 1965. Subfamily Elophorinae, pp. 22-38 in Hatch MH. (ed.), The beetles of the Pacific Northwest. Part IV. University of Washington Publications in Biology 16. Seattle.
      McCorkle DV. 1967. A revision of the species of Elophorus Fabricius in America north of Mexico. Ph.D. Diss., University of Washington iv + 162 pp.
      Motschulsky VI. 1860. Coléoptères de la Sibérie orientale et en particulier des rives de l'Amour, in Schrenk’s Reisen und Forschungen im Amurlande 2:77-257, 6 color plates, St. Petersburg (1861)
      Say T. 1823. Descriptions of coleopterous insects collected in the late expedition to the Rocky Mountains, performed by order of Mr. Calhoun, Secretary of War, under the command of Major Long. Journal of the Philadelphia Academy of Natural History 3: 139-216. VIEW.
      Smetana A. 1985. Revision of the subfamily Helophorinae of the Nearctic region (Coleoptera: Hydrophilidae). Memoirs of the Entomological Society of Canada 131: 1-154.
      Smetana A. 1987. Replacement name for Helophorus frater Smetana 1985. Coleopterists bulletin 41: 262.
      Smetana A. 1988. Review of the family Hydrophilidae of Canada and Alaska (Coleoptera). Memoirs of the Entomological Society of Canada 142. 316 p.

HYDROCHIDAE Thompson, 1859: 75 (Elongated Water Scavenger Beetles)

Previously included in the family Hydrophilidae, morphological data of all life stages as well the consideration of molecular information warranted placing this monophyletic group to family status.
    Hydrochus Leach, 1817: 75 (Subfamily Hydrochinae)
      Hydrochus brevitarsis Knisch, 1922: 90 - Smetana 1988: 12; Hilsenhoff 1995: 42
      Hydrochus currani Brown, 1929: 108 - ON, WI (Smetana 1988: 11-12)
      Hydrochus granulatus Blatchly 1910: 253 - IN, ON, MN, WI, widespread northern (Smetana 1988: 17-18)
        (syn.) Hydrochus ouelleti Leech, 1948
      Hydrochus inaequalis LeConte, 1855: 359 - IN
      Hydrochus neosquamifer Smetana, 1988: 14 - ON, WI (Smetana 1988: 14-15)
      Hydrochus pseudosquamifer Miller, 1965: 22 - IN, ON, WI (Smetana 1988: 15)
      Hydrochus rufipes Melsheimer, 1846: 100 - IL, IN, OH, WI (Smetana 1988: 18)
        (syn.) Hydrochus impressus Zimmermann, 1868
      Hydrochus rugosus Mulsant, 1844: 373 - IN
      Hydrochus scabratus Mulsant, 1844: 372 - Downie and Arnett 1996; see also Smetana 1988: 11
        (syn.) Hydrochus gibbosus Melsheimer, 1846
      Hydrochus setosus Leech, 1948: 35 - Leech 1948: 35 (ESGR), Hilsenhoff 1995: 44
      Hydrochus squamifer LeConte, 1855: 359 - IN, ON, WI (Smetana 1988: 13-14)
        (syn.) Hydrochus laticollis Notman, 1919: 132
      Hydrochus subcupreous Randall, 1838: 40 - IN, WI (Smetana 1988: 15-17)

    References - Taxonomic and Distribution - Hydrochidae

      Blatchley WS. 1910. An illustrated descriptive catalogue of the Coleoptera or beetles (exclusive of Rhynchophora) known to occur in Indiana. Indianapolis. 1386 pp. VIEW.
      Brown WJ. 1929.       Some new species of Coleoptera. The Canadian Entomologist 61: 108- 110.
      Downie NM, Arnett RH. 1996.       The beetles of Northeastern North America. Volume I. Introduction; Suborders Archostemata, Adephaga, and Polyphaga, thru Superfamily Cantharoidea. The Sandhill Crane Press: Gainesville, Florida. xiv + 880 pp.
      Hellman JL. 1975.       A taxonomic revision of the genus Hydrochus of North America, Central America, and West Indies. Unpublished Ph.D. Dissertation, University of Maryland 441 pp.
      Hilsenhoff WL. 1995.       Aquatic Hydrophilidae and Hydraenidae of Wisconsin (Coleoptera). I. Introduction, key to genera, and distribution, habitat, life cycle and identification of species of Helophorus Fabricius, Hydrochus Leach, and Berosus Leach (Hydrophilidae), and Hydraenidae. The Great Lakes Entomologist 28(1): 25-53. VIEW.
      Knisch A. 1922.       Hydrophiliden - Studien (Op.10). Archiv für Naturgeschichte 88. A(5): 87-126.
      Leach WE. 1817. The Zoological Miscellany. Vol. III. London. 151 pp., pl. 121-150. VIEW.
      LeConte JL. 1855. Synopsis of the Hydrophilidae of the United States. Proceedings of the Academy of Natural Sciences of Philadelphia 7: 356-375. VIEW.
      Leech HB. 1948. Some nearctic species of palpicom water beetles, new and old (Coleoptera: Hydrophilidae). The Wasmann Club Collector 7: 33-46. VIEW.
      Melsheimer F. 1846. Descriptions of new species of Coleoptera of the United States. Proceedings of the Academy of Natural Sciences of Philadelphia 2 (1844-1845): 26-53, 98-118.
      Miller DC. 1965. Family Hydrophilidae exclusive Helophorinae and Sphaeridiinae, in Hatch, M.H. (Ed.), The Beetles of the Pacific Northwest. Part IV. University of Washington Publications in Biology 16. 268 pp.
      Mulsant E. 1844. Histoire naturelle des coléoptères de France. Palpicomes. Paris. 7 + 196 pp., 1 pl. VIEW.
      Notman H. 1919. Coleoptera collected at Mooers, Clinton Co. N.Y. September 9-13, with descriptions of new species. Bulletin of the Brooklyn Entomological Society 14: 129- 141. VIEW.
      Randall SW. 1838. Descriptions of new species of coleopterous insects inhabiting the state of Massachusetts . Boston Journal of Natural History 2: 34-52.
      Smetana A. 1988. Review of the family Hydrophilidae of Canada and Alaska (Coleoptera). Memoirs of the Entomological Society of Canada 142: 1-316.
      Thomson CG. 1859, 1867.       Skandinaviens Coleoptera. Vol. I, Vol. IX. Lund, Vol. I, 304 p; Vol. IX, 407 p.
      Zimmermann C. 1869. Synonymical notes on Coleoptera of the United States, with descriptions of new species, from the MSS. of the late Dr. C. Zimmermann. Edited by John L. Leconte, M .D. Transactions of the American Entomological Society 2: 243-259. VIEW.

HYDROPHILIDAE Latreille, 1802: 136 (Water Scavenger Beetles)
The information contained on this list is tentative, based on few observations of museum specimens (currently being assessed) and a limited literature search (Downie and Arnett 1996, Willson 1970). Terrestrial species of Sphaeridiinae (itself a significant portion of the family's biodiversity), including those in the genera Cercyon, Cryptopleurum, Paraceryon, Pemelus, Phaenonotum, Sphaeridium, and Tectosternum, are not included, as they are associated with decaying plant or fungal matter, and animal dung, and are only rarely (or incidentally) collected in aquatic systems. A number of species of Cercyon and Phaenonotum are either semi- or peri-aquatic species, and associated with aquatic habitats, and these are included. Consult Smetana (1988) or Downie and Arnett (1996) for more information.

    Anacaena Thomson, 1859: 18 (Subfamily Hydrobiinae, Tribe Hydrobiini)
      Anacaena lutescens Stephens, 1829: 134 - (as A. limbata (Fabricius, 1792: 82), see Hilsenhoff 1995b: 98 about taxonomic validity; likely parthenogenetic in our area), UMMZ; see also Willson 1970:80-81; Smetana 1988:87-88
        (syn.) Laccobius marshami Stephens, 1839: 92
        (syn.) Anacaena variabilis Sharp, 1870: 255
        (syn.) Brachypalpus ambiguus Rey, 1885: 13
        (syn.) Anacaena immatura Abeille de Perrin, 1901: 59

    Berosus Leach, 1817: 92 (Subfamily Berosinae)
      Berosus aculeatus LeConte, 1855: 363 - Smetana 1988:51; Downie and Arnett 1996
      Berosus fraternus LeConte, 1855: 364 - Downie and Arnett 1996, NMNH (web page database); see also Smetana 1988:54-55
        (syn.) Berosus californicus Motschulsky, 1859: 179
      Berosus hatchi Miller, 1965a: 30 - ON, WI (Smetana 1988:53-54)
      Berosus infuscatus LeConte, 1855: 365 - Charity Island (44.030°N, 83.437°W), specimens in UMMZ, NMNH (web page database)
      Berosus ordinatus LeConte, 1855: 365 - IN, MN (and eastward)
      Berosus pantherinus LeConte, 1855: 364 - IL, IN, OH, ON, WI
      Berosus peregrinus (Herbst, 1797: 314 as Hydrophilus) - UMMZ; see also Smetana 1988:50
        (syn.) Berosus auritus Melsheimer, 1846: 100
        (syn.) Berosus peregrinus, LeConte 1855: 364
        (syn.) Berosus subsignatus LeConte, 1855: 364
        (syn.) Berosus immaculatus Zimmermann, 1869: 249
      Berosus striatus (Say, 1825: 188 as Hydrophilus) - UMMZ, NMNH (web page database); see also Smetana 1988:51-52
      Berosus stylifer Horn, 1873: 121 - Smetana 1988:55-56
        (syn.) Berosus falcatus Sharp, 1882: 81

    Cercyon Leach, 1817: 95 (Subfamily Spaheridiinae, Tribe Cercyonini)
      Cercyon (Cercyon) cinctus Smetana, 1978: 92 - Smetana 1988: 148 (peri-aquatic, similar habitat preferences with marinus)
      Cercyon (Cercyon) connivens Fall, 1924b: 250 - Smetana 1988: 141 (peri-aquatic)
      Cercyon (Cercyon) herceus Smetana, 1978: 66 - Smetana 1988: 142-143 (peri-aquatic)
        (syn.) Cercyon tristis, Horn 1890b: 303 (nec Illiger, 1801)
      Cercyon (Cercyon) erraticus Smetana, 1978: 80 - Smetana 1988: 144 (peri-aquatic)
      Cercyon (Cercyon) mendax Smetana, 1978: 83 - Smetana 1988: 145 (peri-aquatic)
      Cercyon (Cercyon) praetextatus (Say, 1825: 190 as Sphaeridium) - Smetana 1988: 145-146
        (syn.) Cercyon testaceus Blatchley, 1923: 16
      Cercyon (Cercyon) marinus Thomson, 1853: 54 - Smetana 1988: 147-148 (semi-aquatic)
      Cercyon (Prostercyon) roseni Knisch, 1922: 98 - Smetana 1988:136-137 (peri- to semi-aquatic, along wetlands, ponds, bogs and lakes)
        (syn.) Cercyon opacellus Fall, 1924b: 249

    Chaetarthria Stephens, 1833: 22 (Subfamily Chaetarthriinae)
      Chaetarthria atra (LeConte, 1863: 24 as Cyllidium) - IL, IN (Smetana 1988: 57-58)
        (syn.) Chaetarthria nigrella, Wickham 1895: 185 (nec LeConte, 1861b)
      Chaetarthria pallida (LeConte, 1861: 342 as Cyllidium) - Cheboygan Co., UMMZ, NMNH (web page database); see also Smetana 1988: 58
        (syn.) Cyllidum nigriceps LeConte, 1861: 342

    Crenitis Bedel, 1881: 306 (Subfamily Hydrobiinae)
      Crenitis digesta (LeConte, 1855: 373 as Hydrobius) - Willson 1970: 78-79; see also Smetana 1988: 81-82)
        (syn.) Paracymus digestus Winters, 1926: 56
        (syn.) Crenophilus digestus d'Orchymont, 1942b: 30

    Cymbiodyta Bedel, 1881: 307 (Subfamily Hydrobiinae, Tribe Helocharini)
      Cymbiodyta acuminata Fall, 1924a: 87 - UMMZ; Willson 1970: 52-53; Smetana 1974: 68-70; see also Smetana 1988: 110-111
      Cymbiodyta blanchardi Horn, 1890a: 254 - UMMZ; Willson 1970: 53; see also Smetana 1974: 61-64; Smetana 1988: 107-108
      Cymbiodyta chamberlaini Smetana, 1974: 57 - UMMZ; Smetana 1974: 57-61; Smetana 1988: 106-107
      Cymbiodyta minima Notman, 1919: 133 - UMMZ, NMNH (web page database); Willson 1970: 54; Smetana 1974: 73-76; see also Smetana 1988: 111-112
        (syn.) Hydrobius marginellus Kirby, 1837: 170, in Richardson
        (syn.) Philidrus lacustris Horn, 1873: 131 (nec LeConte 1855)
        (syn.) Cymbiodyta lacustris Horn 1890a: 254, 259; Wickham, 1895: 214
      Cymbiodyta semistriata (Zimmermann, 1869: 250 as Philhydrus) - UMMZ, NMNH (web page database); Smetana 1974: 48-51; see also Smetana 1988: 103, 105
        (syn.) Philhydrus fimbriatus LeConte, 1855: 369 (nec Melsheimer 1846)
        (syn.) Philidrus fimbriatus Provancher, 1877: 217
        (syn.) Cymbiodyta fimbriata, Horn 1890a and authors
      Cymbiodyta toddi Spangler, 1966: 211 - Willson 1970: 56; Smetana 1974: 51-54; see also Smetana 1988: 104, 106
      Cymbiodyta vindicata Fall, 1924a: 86 - UMMZ, NMNH (web page database); Willson 1970: 55-56; Smetana 1974: 64-67; see also Smetana 1988: 108-109

    Dibolocelus Bedel, 1891: 309 (Subfamily Hydrophilinae)
      Dibolocelus ovatus (Gemminger & Harold, 1868: 476 as Hydrophilus, nom. nov.) - Willson 1970; see also Smetana 1988: 124
        syn.) Hydrophilus ovilis Ziegler, 1844: 45 (nec Laport, 1840)

    Enochrus Thomson, 1859: 18 (Subfamily Hydrobiinae, Tribe Helocharini)
      Enochrus (Methydrus) blatchleyi (Fall, 1924a: 85 as Philhydrus) - Willson 1970: 62; see also Smetana 1988: 92
      Enochrus (Methydrus) cinctus (Say, 1824: 276 as Hydrophilus) - Willson 1970: 63-64; record at Albertson College of Idaho Collection; see also Smetana 1988: 92-93
        (syn.) Philhydrus limbalis Melsheimer, 1846: 101
      Enochrus (Lumetus) collinus Brown, 1931: 118 - MN, WI. MB-VT, expect in n. MI (Hilsenhoff 1995b: 106)
      Enochrus (Methydrus) consors LeConte, 1863: 24 as Philhydrus) - Willson 1970: 65; see also Smetana 1988: 93)
      Enochrus (Methydrus) consortus Green, 1946: 61 - Willson 1970: 64-65; see also Smetana 1988: 93-94
      Enochrus (Lumetus) diffusus (LeConte, 1855: 371 as Philhydrus) - record at Albertson College of Idaho Collection; western species with isolated eastern populations (Smetana 1988: 99); see also Willson 1970: 66-67
      Enochrus (Lumetus) hamiltoni (Horn, 1890: 249 as Philhydrus) - Downie and Arnett 1996; see also Smetana 1988: 99-100
        (syn.) Philhydrus lividus Walker, 1866: 310, (nec. Forster) fide Miller 1964:71
        (syn.) Philhydrus conjunctus Fall, 1901: 217
        (syn.) Enochrus collinus Brown, 1931: 118
        (syn.) Enochrus diffusus Winters 1927:23 (partim) fide Leech 1950: 253
        (syn.) Enochrus horni Leech, 1950: 250
        (syn.) Enochrus hamiltoni pacificus Leech, 1950: 255
        (syn.) Enochrus hamiltoni pyretus Leech, 1950: 255
      Enochrus (Methydrus) ochraceus (Melsheimer, 1846: 101 as Philhydrus) - Willson 1970: 62-63; record at Albertson College of Idaho Collection; see also Smetana 1988: 95
        (syn.) Philhydrus lacustris LeConte, 1855: 369
        (syn.) Philhydrus simplex LeConte, 1863: 24
      Enochrus (Methydrus) perplexus (LeConte, 1855: 371 as Philhydrus) - Willson 1970: 54-55 (as C. fimbriata), 65-66; see also Smetana 1988: 94
        (syn.) Cymbiodyta fimbriatua Melsheimer, 1846: 101
      Enochrus (Methydrus) pygmaeus nebulosus (Say, 1824: 277 as Hydrophilus) - Willson 1970: 60-61; see also Smetana 1988: 96
        (comb.) Hydrophilus pygmaeus Fabricius, 1792: 186 (Gundersen 1977: 256)
      Enochrus (Methydrus) sayi Gundersen, 1977: 262 - Downie and Arnett 1996; Smetana 1988: 97

    Helocombus Horn, 1890: 241 (Subfamily Hydrobiinae, Tribe Helocharini)
      Helocombus bifidus (LeConte, 1855: 371 as Philhydrus) - Willson 1970: 50-51; see also Smetana 1988: 113

    Hydrobius Leach, 1815 (Subfamily Hydrobiinae, Tribe Hydrobiini)
      Hydrobius fuscipes (Linnaeus, 1758: 411 as Dytiscus) - Willson 1970: 69, NMNH (web page database), record at Albertson College of Idaho Collection; see also Smetana 1988: 69-70
      Hydrobius melaenus (Germar, 1824: 96) Sphaeridium (orig.) - Willson 1970: 69-71 (as H. globosus); see also Smetana 1988: 70-71
        (syn.) Hydrophilus globosus Say, 1824: 96
        (syn.) Hydrobius globosus LeConte, 1855: 372
        (syn.) Hydrobius globulosus Provancher, 1877: 218

    Hydrochara Berthold, 1827: 355 (Subfamily Hydrophilinae)
      Hydrochara leechi Smetana, 1980: 38 - IL, OH, WI, may occur in s LP (Smetana 1980: 38-41)
      Hydrochara obtusata (Say, 1823: 202 as Hydrophilus) - Willson 1970: 22-23; NMNH (web page database); Smetana 1980: 24-30; see also Smetana 1988: 127
      Hydrochara simula Hilsenhoff & Tracy 1982: 99 - Hilsenhoff and Tracy 1982: 101; see also Smetana 1988: 128
      Hydrochara soror Smetana, 1980: 30 - Smetana 1980: 30-34; see also Smetana 1988: 128
      Hydrochara spangleri Smetana, 1980: 34 - IL, IN, OH, WI, may occur in sw LP (Smetana 1980: 34-36)

    Hydrophilus Geoffroy, 1762 (Subfamily Hydrophilinae)
      Hydrophilus triangularis Say, 1823: 201 - Willson 1970: 24-25; see also Smetana 1988: 123-124

    Laccobius Erichson, 1837 (Subfamily Hydrobiinae, Tribe Hydrobiini)
      Laccobius agilis (Randall, 1838a: 19 as Hydrophilus) - Willson 1970: 38-39; see also Smetana 1988: 61-62
        (syn.) Laccobius ellipticus, Stace Smith 1930: 23 (nec LeConte, 1855)
      Laccobius carri d'Orchymont, 1942a: 12 - ON, may occur in UP (Smetana 1988: 67-68)
        (syn.) Laccobius pacificus Miller 1965d: 60
      Laccobius cinereus columbianus Miller, 1965d: 59 - Downie and Arnett 1996; see also Smetana 1988: 64-65
      Laccobius minutoides d'Orchymont, 1942: 10 - Willson 1970: 39-40; see also Smetana 1988: 62-63
      Laccobius reflexipennis Cheary, 1971: 101 - ON, WI (Smetana 1988: 66-67)
      Laccobius spangleri Cheary, 1971: 93 - Willson 1970: 40-44; Cheary 1971; NMNH (web page database); see also Smetana 1988: 67
        (inv.) Laccobius spangleri Willson, 1970, unpublished MS thesis
      Laccobius teneralis Cheary, 1971: 107 - ON, may occur in s. LP (Smetana 1988: 65-66)
      Laccobius truncatipenis Miller, 1965d: 61 - Willson 1970: 44-48 (as L. arenarius); Cheary 1971 (as L. arenarius); NMNH (web page database); see also Smetana 1988: 68-69
        (inv.) Laccobius arenarius Willson 1970, unpublished MS thesis
        (syn.) Laccobius arenarius Cheary, 1971

    Limnohydrobius Reitter, 1909 (Subfamily Hydrobiinae, Tribe Hydrobiini)
      Limnohydrobius tumidus (LeConte, 1855: 372 as Hydrobius) - IL, IN (GBIF, accessed 6/5/2020) (expect in sw LP)

    Paracymus Thomson, 1867: 119 (Subfamily Hydrobiinae, Tribe Hydrobiini)
      Paracymus confluens Wooldridge, 1966: 716 - Wooldridge 1966; Willson 1970: 74-75; Smetana 1988: 75-76
      Paracymus confusus Wooldridge, 1966: 719 - Downie and Arnett 1996; see also Willson 1970: 75; Smetana 1988: 77
      Paracymus despectus (LeConte, 1863: 723 as Hydrobius) - Willson 1970: 73-74; NMNH (web page database); see also Smetana 1988: 78
      Paracymus subcupreus (Say, 1825: 189 as Hydrobius) - Willson 1970: 75-76, NMNH (web page database); see also Smetana 1988: 76-77

    Phaenonotum Sharp, 1882: 97 (Subfamily Spaheridiinae, Tribe Sphaeridiini)
      Phaenonotum exstriatum (Say, 1835: 171 as Hydrophilus) - Willson 1970: 13-14; Smetana 1988: 130 (often semi-aquatic, at edges of wet habitats and water, wet moss and Sphagnum)
        (comb.) Cyclonotum estriatum LeConte, 1855: 373 (unjustified emendation)
        (syn.) Cyclonotum semiglobosum Zimmermann, 1869: 250
        (syn.) Phaenonotum dubium Sharp, 1882: 98 (spell.)

    Sperchopsis LeConte, 1862: 47 (Subfamily Hydrobiinae, Tribe Hydrobiini)
      Sperchopsis tessellatus (Ziegler, 1844: 44 as Spercheus) - Willson 1970: 71-72; record at Albertson College of Idaho Collection; E. Bright coll.; see also Smetana 1988: 72
        (syn.) Sperchopsis tessellatus LeConte, 1861: 47
        (syn.) Hydrobius tessellatus Horn, 1873: 133
        (syn.) Hydrocyclus tessellatus Winters, 1926: 53

    Tropisternus Solier, 1834: 302 (Subfamily Hydrophilinae)
      Tropisternus blatchleyi modestus d'Orchymont, 1938: 437 - Willson 1970: 32 (as T. modestus); see also Smetana 1988: 119-120
        (syn.) Tropisternus modestus d'Orchymont, 1938: 437; Wooldridge 1965: 205
      Tropisternus columbianus Brown, 1931: 117 - Willson 1970: 29-30; see also Smetana 1988: 122
      Tropisternus ellipticus (LeConte, 1855: 368 as Hydrophilus) - IL, WI (Smetana 1988: 118-119; see also Willson 1970: 29)
        (syn.) Tropisternus affinis Motschulsky, 1859: 175
        (syn.) Tropisternus concolor Sharp, 1882: 57
      Tropisternus glaber (Herbst, 1797: 298 as Hydrophilus) - Willson 1970: 33-34; Ryker 1972; see also Smetana 1988: 121
      Tropisternus lateralis nimbatus (Say, 1823: 203 as Hydrophilus) - Willson 1970: 28; Ryker 1972 (as T. nimbatus); see also Smetana 1988: 118
        (syn.) Tropisternus nimbatus Summers, 1874: 82
        (syn.) Tropisternus lateralis Horn, 1876: 251
      Tropisternus mixtus (LeConte, 1855: 368 as Hydrophilus) - Willson 1970: 30-31; Ryker 1972; see also Smetana 1988: 119
      Tropisternus natator d'Orchymont, 1938: 436 - Willson 1970: 32-33; Ryker 1972; see also Smetana 1988: 120-121
        (syn.) Tropisternus glaber, LeConte, 1859: 36; Wooldridge, 1967
        (syn.) Hydrophilus glaber, LeConte, 1855: 368 (nec Herbst, 1797: 298)

    References - Hydrophilidae [under construction]

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    Page edits:
      June 21, 2020
      • Created separate species-list page for Hydrophiloidea, allowing for Coleoptera pages to be more manageable. Added more links to original literature.
      • Removed Hydrochus rugosus Mulsant - unlikely to be found in Michigan, and record from Indiana has a doubtful locality validity (Hellman 1975, ref. in Hydrochidae)
      November 21, 2012
      • Beginning to keep track of changes to the web site pages
      • Removed individual pages for families into one long list, families accessed from left menu via anchor redirects within page.

    Page created: November 01, 2002; Last update July 20, 2020 (EB)