Order Beetle | Rank Genus | |
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Family GeorissidaeLaporte, 1819 Similar Spercheidae, Beetle, Heteroceridae, Sphaerites, Limnichidae | ||
Georissus, also called minute mud-loving beetles, is the only genus in the beetle family Georissidae (or Georyssidae). They are tiny insects living in wet soil, often near water. Found on every continent except Antarctica.
Contents
Characteristics
Georissidae are small beetles (length 1–2 mm). They have a broadly oval body whose outline is more or less interrupted between the pronotum and the elytra. The head and pronotum are granulate, the prosternum is rudimentary, without intercoxal processes. The anterior coxae and trochanters are fused. The basal ventrite is very large.
Systematics and evolution
There are about 75 living species, including:
The genus is divided into three subgenera (Georissus, Neogeorissus and Nipponogeorissus). Formerly it was included within the family Hydrophilidae. Recent molecular data indicate, that they belong to a clade comprising the small groups of Hydrophiloidea - Epimetopidae, Hydrochidae, Helophoridae and Georissidae.
