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.
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.
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.
There are over 2,154 species of beetles species of Coleoptera native to Ireland. These are disposed in 84 families. By contrast there are 4,034 species of Coleoptera in the British Isles, consisting of 106 families . The largest beetle families in Ireland are the rove beetles (Staphylinidae) with 641 species, the weevils (Curculionidae) with 214 species, and the ground beetles (Carabidae) with 210 species.List of the Cenozoic life of Alaska
This list of the Cenozoic life of Alaska contains the various prehistoric life-forms whose fossilized remains have been reported from within the US state of Alaska and are between 66 million and 10,000 years of age.List of the Cenozoic life of Washington (state)
This list of the Cenozoic life of Washington contains the various prehistoric life-forms whose fossilized remains have been reported from within the US state of Washington and are between 66 million and 10,000 years of age.List of the prehistoric life of Alaska
This list of the prehistoric life of Alaska contains the various prehistoric life-forms whose fossilized remains have been reported from within the US state of Alaska.Psammophory
Psammophory is a method by which certain plants armor themselves with sand on their body parts making chances less for them to be eaten by animals. University of California graduate students have listed over 200 species of desert plants that coat themselves in sand and they trap sand that the wind blows at them. Over 200 species of plants hailing from 88 genera in 34 families have been identified as psammorphorous.The term was first proposed in 1989 by scientists studying the habits of the beetle Georissus which actively covers its elytra with sand or mud particles.
Extant Coleoptera families