''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on

algae Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

; they occur on all continents except Antarctica. Three species occur in the United States. The overall form of the beetle is convex, glossy, dark brown or black with some markings possible. The head is prominent, with relatively large eyes set far apart, and capitate antennae. Total length ranges from . The beetles occur in a variety of damp environments, including mud, under stones, among plant roots and leaf litter, and in mosses in bogs. They store some air underneath their elytra. Females produce a single large egg at a time. The family used to be known as "Sphaeriidae", but the name was preoccupied by a family of freshwater clams. The name was inappropriately replaced with "Microsporidae" (by changing the genus name to ''Microsporus''), but this act has been superseded by a return to the use of ''Sphaerius'' and a reformation of the family name as Sphaeriusidae. The position of the family within Coleoptera has also changed a number of times. Ross H. Arnett, Jr. and

Michael C. Thomas Michael Charles Thomas (May 5, 1948 – October 14, 2019) was an American entomologist who co-authored the book series ''American Beetles''. Born in Miami, Florida, Thomas graduated from the University of South Florida in 1970 with a Bachelor o ...

, ''

American Beetles ''American Beetles'' is the single most comprehensive description of the beetles of North America north of the tropical area of Mexico. It was started by Ross H. Arnett, Jr. as an update of his classic ''The Beetles of the United States''; along ...

'' (CRC Press, 2001)

Species

*'' Sphaerius acaroides'' *''

Sphaerius africanus ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius alticola ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius coenensis ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius coomani ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius cribratus ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ...

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Sphaerius favosus ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ...

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Sphaerius gustavlohsei ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius hispanicus ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius humicola ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius laeviventris ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius madecassus ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius minutus ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius politus ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius obsoletus ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius ovensensis ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius papulosus ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius perlaevis ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius scutellaris ''Orthoperus scutellaris'' is a species of minute hooded beetle in the family Corylophidae. It is found in North America North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is ...

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Sphaerius silvicola ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

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Sphaerius spississimus ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ...

'' *'' Sphaerius tesselatus'' *''

Sphaerius texanus ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ...

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Sphaerius tropicus ''Sphaerius'' is a genus of beetles, comprising 23 species, which are the only living members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae; they occur on all continents ex ...

Fossil Sphaeriusidae

* †''Burmasporum'' Kirejtshuk 2009 Burmese amber, Myanmar,

Cenomanian The Cenomanian is, in the ICS' geological timescale, the oldest or earliest age of the Late Cretaceous Epoch or the lowest stage of the Upper Cretaceous Series. An age is a unit of geochronology; it is a unit of time; the stage is a unit in the s ...

References

External links

Sphaeriusidae
Tree of Life {{Taxonbar, from1=Q606681, from2=Q16209130 Myxophaga genera Taxa named by Joseph Waltl