Sphaerius is a genus of beetle, comprising 23 species, which are the only members of the family Sphaeriusidae. They are typically found along the edges of streams and rivers, where they feed on algae, occurring on all continents except Antarctica. Only 3 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 0.5รข"1.2 mm.
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 was previously 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replaced with "Microsporidae" (by changing the genus name to Microsporus) but this act has very recently been superseded by a return to the use of Sphaerius and a re-formation of the family name as Sphaeriusidae. The position of the family within Coleoptera has also changed a number of times.
Species
- Sphaerius acaroides
- Sphaerius africanus
- Sphaerius alticola
- Sphaerius coenensis
- Sphaerius coomani
- Sphaerius cribratus
- Sphaerius favosus
- Sphaerius gustavlohsei
- Sphaerius hispanicus
- Sphaerius humicola
- Sphaerius laeviventris
- Sphaerius madecassus
- Sphaerius politus
- Sphaerius obsoletus
- Sphaerius ovensensis
- Sphaerius papulosus
- Sphaerius perlaevis
- Sphaerius scutellaris
- Sphaerius silvicola
- Sphaerius spississimus
- Sphaerius tesselatus
- Sphaerius texanus
- Sphaerius tropicus
References
- Ross H. Arnett, Jr. and Michael C. Thomas, American Beetles (CRC Press, 2001)
External links
Sphaeriusidae Tree of Life