The information contained below was compiled by the late Warren U. Brigham and is available in several files on his webpages at the Illinois Natural History Survey. I have reorganized the information into a single file.
Sharon Knight Jasper
Checklist of Genera of the US, US Territories, and Canada
* Subfamily Noterinae Thomson 1860:34.
o Genus Notomicrus Sharp 1880-1882:260, 834.
o Genus Suphis Aube, 1836:208.
+ syn. Colpius LeConte 1861:40.
o Genus Pronoterus Sharp 1880-1882:263, 835.
o Genus Mesonoterus Sharp 1882:4.
o Genus Hydrocanthus Say 1823:105.
+ subgen. s.str.
+ subgen. Guignocanthus Young 1985:91.
o Genus Suphisellus Crotch 1873:397
+ Suphisellus Zimmermann 1921:187
A portion of this treatment was adapted from a manuscript prepared by R. E. Roughley, University of Manitoba.
Notomicrus Sharp 1880-1882:260
* Type species: Notomicrus brevicornis Sharp 1880-1882, subsequently fixed by Guignot (1946:115)
The genus Notomicrus contains some of the smallest of all aquatic beetles, ranging in length from 1.0 mm to just over 1.6 mm in total length. Currently, 9 species are recognized: eight in the New World, plus one in the Australian and Oriental regions. Guignot (1946) designates the type species. Zimmermann (1927) and Balfour-Browne (1939) consider all the Old World species to be identical with Notomicrus tenellus (Clark), and with Watts (1985), define the Australian and Oriental species. Beutel and Roughley (1987) discuss the systematic position of the genus.
Checklist of Notomicrus
* Notomicrus nanulus (LeConte 1863:22)
o Hydroporus nanulus LeConte 1863:22
* Notomicrus sharpi Balfour-Browne 1939:98
o Notomicrus politus Sharp 1882:3, by Balfour-Browne 1939:98
Key to Species of Notomicrus New World - Young (1978), 8 species
Suphis Aube 1836:208
* Type species: Suphis cimicoides Aube 1836:209
* Syn. Colpius LeConte 1861:40, by Spangler and Folkerts (1973)
o Type species: Colpius inflatus LeConte 1863:22
The genus Suphis is Nearctic and Neotropical in distribution and contains 11 species. Spangler and Folkerts (1973) describe the larva of Suphis inflatus.
Checklist of Species of the US, US Territories, and Canada
* Suphus inflatus (LeConte 1863:22)
o Colpius inflatus LeConte 1863:22, by Spangler and Folkerts (1973:506)
Type specimens: Holotype in LeConte Collection, Museum of Comparative Zoology?.
Type Locality: Florida (Spangler and Folkerts 1973:501) or Louisiana (Young 1954:125).
Distribution: Cuba and United States: Alabama, Florida, Georgia, Louisiana, and South Carolina and Texas.
Key to Species of Suphis: Grosso (1994) keys 10 species, omitting only the nearctic Suphis inflatus LeConte 1863:22.
Suphisellus Crotch 1873:397
* Type species: Suphisellus bicolor (Say 1831:5), by subsequent designation of Leech 1948:403
The source of the genus name Suphisellus and its genotype have been problematic. In discussing the genus Colpius, Crotch (1873:397) stated "This genus appears to me very near Suphis, the type of which is a globose and similarly marked species (S. cimicoides), but which I have not seen. If these two were shown to be congeneric, the species above under Suphis might receive the name Suphisellus." The species he placed under Suphis were Noterus bicolor Say, Suphis lineatus Horn, and Suphis puncticollis Crotch. Crotch was correct in recognizing the similarity between Suphis and Colpius, as the two are now considered congeneric under Suphis. The three species Crotch included under Suphis are now placed in Suphisellus.
In 1880, Sharp (1880-1882:269) erected the genus Canthydrus for a portion of the noterids previously included within Hydrocanthus, noting later (1880- 1882:839) "This genus has been mixed with Hydrocanthus, but was separated by Crotch so far as regards the North American species; he suggested for it the name of Suphisellus, but not in a formal manner - only as it were hypothetically, and I have thought it on the whole better to use a new name." Thus, the three species of "Suphis" of Crotch moved to Canthydrus.
In 1921, Zimmermann (1921:187) described the genus Suphisellus for the American species previously included in Sharp's genus Canthydrus. Zimmermann then described four new species of Suphisellus, the first of which was Suphisellus variicollis Zimmermann 1921:397. Zimmermann's paper makes no note of Crotch's use of Suphisellus. Guignot (1946) identified or designated genotypes of numerous aquatic beetles. For Suphisellus, he states (Guignot 1946:116) "Suphisellus Zimm. - Type: variicollis Zimm., que je designe."
Leech (1948:403) apparently had not seen Guignot's paper, and wrote under Suphisellus, "Genotype: There is no indication in the literature at hand that a genotype has been assigned. I hereby designate Noterus bicolor Say, 1831:5, as the type of Suphisellus Crotch." In the following paragraph, Leech states "The species of this genus occur in the New World, and previous to Zimmermann's paper  on the South American forms, were included in Canthydrus Sharp. However, the name chosen by Zimmermann had already been proposed, albeit obscurely, by Crotch."
Leech (1970) discussed these problems and concluded that it was correct to credit the genus to Crotch (1873:397), with the genotype Noterus bicolor Say (1831:5), fixed by subsequent designation by Leech (1948:403). Suphisellus Zimmermann (1921:187) should be considered a junior synonym (and homonym). Guignot (1946:116) was in error designating as a genotype, a species not originally included in Suphisellus by Crotch. Suphisellus is represented in the Americas north of Colombia by 17 species. The South American species are numerous, poorly known, and in need of revision (Young 1979).
Key to species of Suphisellus: North and Central America - Young 1979, 17 species
Type specimens: Suphisellus bicolor (Say 1834:446)
Type locality: Louisiana, Mr. Barabino. Subsequently restricted to New Orleans by Leech (1970:243).
Checklist of Suphisellus
Suphisellus bicolor (Say 1834:446)
* Suphisellus bicolor subsp. bicolor (Say 1834:446)
o Noterus bicolor Say 1834:446
o Suphisellus bicolor subsp. bicolor (Say 1834:446), new combination by Young (1979:425)
Distribution: United States: Alabama, Arkansas, Indiana, Louisiana, Mississippi, and Texas. Introduced to California (Leech 1970).
* Suphisellus bicolor subsp. punctipennis (Sharp 1880-1882:270)
o Canthydrus punctipennis Sharp 1880-1882:270
o Suphisellus bicolor subsp. punctipennis (Sharp 1880-1882:270), new combination by Young (1979:426)
Type specimens: Lectoholotype male in the British Museum (Natural History).
Type locality: "Carolina #509".
Distribution: United States: Alabama, Delaware, Georgia, Illinois, Indiana, Kentucky, New Jersey, North Carolina, Tennessee, South Carolina, and Virginia.
Suphisellus gibbulus (Aube 1838:414)
* Suphis gibbulus Aube 1838:414
Type specimens: Lectoholotype male in British Museum (Natural History).
Type locality: United States; lectoholotype locality: "Amer Bor. ex. Mus. DeJean".
Distribution: United States: Alabama, Georgia, Florida, South Carolina.
Suphisellus insularis (Sharp 1880-1882:270)
* Canthydrus insularis Sharp 1880-1882:270
* Canthydrus simplex Sharp 1882:5, by Young (1979:422)
* Canthydrus similaris Sharp 1887:748, by Young (1979:422)
* Canthydrus floridanus Blatchley 1914:63, by Young (1979:422)
Type specimens: Holotype male in the British Museum (Natural History)?
Type locality: San Domingo, Coll. Biuvouloir [Young (1979:421) locates this as: Cuba, Villas Province, Santo Domingo].
Distribution: Cuba, Dominican Republic, Guatemala, Haiti, Mexico, and Puerto Rico.
Suphisellus parsoni Young 1952:157
Type specimens: Holotype male in California Academy of Sciences.
Type locality: United States: Florida, Highlands County, Sebring (at light), 20.Jul.1942, C. T. Parsons.
Distribution: United States: Florida and Georgia.
Suphisellus puncticollis (Crotch 1873:397)
* Suphis puncticollis Crotch 1873:397
* Suphisellus puncticollis Crotch 1873:397, by Young (1954:131)
Type specimens: Type possibly in the LeConte Collection, Museum of Comparative Zoology. The type was collected by LeConte.
Distribution: Canada; United States: Massachusetts to Michigan, south to Florida.
Hydrocanthus Say 1823:105
* Type species: Hydrocanthus iricolor Say 1823:105, by monotypy
Hydrocanthus is represented by 46 species distributed worldwide, excepting the Palaearctic region. Of these, six occur in North America north of Mexico.
Checklist of Species of the US, US Territories, and Canada
* subgen. s.str.
* Hydrocanthus advena Sharp 1880-1882:281
* Hydrocanthus atripennis Say 1834:447
o Hydrocanthus texanus Sharp 1880-1882:280, by Young 1985:97
* Hydrocanthus iricolor Say 1823:105
o Hydrocanthus similator Zimmermann 1927 (1928):165, by Young 1985:97
* Hydropcanthus oblongus Sharp 1880-1882:280
* Hydrocanthus regius Young 1953:2
* subgen. Guignocanthus Young 1985:91, by original designation
* Hydrocanthus debilis Sharp 1880-1882:281
o Hydrocanthis finitismus Guignot, by Young (1985:98)
Type specimens: Type in the Royal Museum at Brussels. Type locality: Guadeloupe, Basseterre.
Distribution: Antilles: Cuba?, Guadeloupe, Hispaniola, Puerto Rico, Trinidad.
Hydrocanthus atripennis Say 1834:447
* Hydrocanthus texanus Sharp 1880-1882:280, by Young 1985:97
Distribution: Eastern Mexico to southern Canada west of the Appalachians, common in Texas, Arkansas, Louisiana, and Mississippi north to southern Illinois and southern Indiana; rare eastward in Florida and the Atlantic coastal plain north to the Carolinas (Young 1985:97).
Hydrocanthus debilis Sharp 1880-1882:281
* Hydrocanthis finitismus Guignot, by Young (1985:98)
Type specimens: Holotype male in British Museum (Natural History). Type locality: South
America, Bahia, Amazon's Valley.
Distribution: Texas to Paraguay (Young 1985:98), Bolivia (Guignot 1957:5).
Hydrocanthus iricolor Say 1823:105
* Hydrocanthus similator Zimmermann 1927 (1928):165, by Young 1985:97
* Hydrocanthus tricolor Say, mis-spelled by Guignot (1959:507)
Distribution: Eastern North America from Maine and Ontario to Michigan, northern Indiana, and south to South Carolina and Georgia.
Hydrocanthus oblongus Sharp 1880-1882:280
Type specimens: Type in the British Museum (Natural History). Type locality: North America.
Distribution: Bahamas, Cuba, and United States: Gulf and Atlantic coastal plains from Texas to the Carolinas.
Hydrocanthus regius Young 1953:2
Type specimens: Holotype male in Museum of Zoology, University of Michigan. Type locality: United States: Florida, Alachua County, Bivans Arm of Payne's Prairie, Aug.23.1950, J. C. Jackson and F. N. Young.
Distribution: United States: Florida and Georgia.
Aubé, C. 1838. Species general des Coleopteres. VI. Species general des Hydrocanthares et Gyriniens, par le docteur Ch. Aube; pour faire suite au species general des Coleopteres de la collection de M. Le Comte Dejean. Mequignon-Marvis pere et fils, Paris. xvi + 804 pp.
Balfour-Browne, J. 1939. A contribution to the study of the Dytiscidae. (Coleoptera, Adephaga). Ann. Mag. Nat. Hist. Series 11. 3(13):97-114.
Beutel, R. G. and R. E. Roughley. 1987. On the systematic position of the genus Notomicrus Sharp (Hydradephaga: Coleoptera). Canadian J. Zool. 65(8):1898-1905.
Blatchley, W. S. 1914. Notes on the winter and early spring Coleoptera of Florida, with descriptions of new species. Canadian Entomol. 46:88-92.
Crotch, G. R. 1873. Revision of the Dytiscidae of the United States. Trans. Amer. Entomol. Soc. 4:383-424.
Grosso, L. E. 1994. Revision de las especies neotropicales del genero Suphis Aube, con la description de S. Ticky n. sp. (Coleoptera - Noteridae). [Revision of the newtropical species of the genus Suphis Aube (Coleoptera- Noteridae)]. Acta Zool. Lilloana 42(2):225-238.
Guignot, F. 1946. Genotypes des Dytiscoidea et des Gyrinoidea. Rev. Francaise d'Entomol. 13:112-118.
Guignot, F. 1957. Beitrage zur Kenntnis der Insektenfauna Boliviens. Teil II. Coleoptera I. Dytiscidae. Opusc. Zool., Munich 6:1-10.
Guignot, F. 1959. Revision des Hydrocanthares d'Afrique (Coleoptera Dytiscoidea), Part 2. Ann. Mus. Congo Belgique (ser 8) Sci. Zool. 78:317-648.
LeConte, J. L. 1863. New species of American Coleoptera. Smithsonian Misc. Coll. 6(167):1-86.
Leech, H. B. 1948. Contributions toward a knowledge of the insect fauna of Lower California. No. 11. Coleoptera: Haliplidae, Dytiscidae, Gyrinidae, Hydrophilidae, Limnebiidae. Proc. California Acad. Sci. 24(11):375-484 + pls. 20-21.
Leech, H. B. 1970. Copelatus glyphicus (Say) and Suphisellus bicolor (Say), water beetles new to California and presumably introduced (Coleoptera: Dytiscidae and Noteridae). Proc. California Acad. Sci. 37:237-247.
Mouchamps, R. 1955. Note systematique sur le genere Suphis Aube. Bull. Inst. Royal Sci. Nat. Belgique 31(57):1-7.
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Sharp, D. 1880-1882. On aquatic carnivorous Coleoptera or Dytiscidae. Sci. Trans. Royal Dublin Soc. 2(new series), part 2:179-1003 + plates vii-xviii. 1882-1887. Biologia Centrali Americana, Insecta Coleoptera, I. 2:xv + 824 pp + 19 pls.
Spangler, P. J., and G. W. Folkerts 1973. Reassignment of Colpius inflatus and a description of its larva (Coleoptera: Noteridae). Proc. Biol. Soc. Washington 86(43):501-510.
Watts, Ch. H. S. 1985. A faunal assessment of Australian Hydradephaga. Proc. Acad. Nat. Sci. Philadelphia 137:22-28.
Young, F. N. 1952. A new species of Suphisellus from Florida (Coleoptera: Noteridae). Florida Entomol. 35(4):157-158.
Young, F. N. 1953. A new species of Hydrocanthus from Florida, with notes on other species of the genus (Coleoptera: Noteridae). Occ. Pap. Mus. Zool. Univ. Michigan 549:1-6.
Young, F. N. 1978. The New World species of the water-beetle genus Notomicrus (Noteridae). Syst. Entomol. 3(3):285-293.
Young, F. N. 1979. Water beetles of the genus Suphisellus Crotch in the Americas north of Colombia (Coleoptera: Noteridae). Southwest. Nat. 24(3):409-429.
Young, F. N. 1985. A key to the American species of Hydrocanthus with descriptions of new taxa (Coleoptera: Noteridae). Proc. Acad. Nat. Sci. Philadelphia 137(1):90-98.
Zimmermann, A. 1921. Beitrage zur Kenntnis der sudamerikanischen Schwimmkaferfauna nebst 41 Neubeschreibungen. Arch. Naturgeschichte 87(3):181-206.
Zimmermann, A. 1927. Dytiscidae, pp. 15-19. In Insects of Samoa and other Samoan terrestrial Arthropoda, part 4, fasc. 1.
Zimmermann, A. 1927/1928. Neuer Beitrag zur Kenntnis der Schwimmkafer. Wien. Entomol. Zeit. 44:165-187.