Everettia is a genus

Genus

In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...

 of air-breathing land snail

Snail

Snail is a common name applied to most of the members of the molluscan class Gastropoda that have coiled shells in the adult stage. When the word is used in its most general sense, it includes sea snails, land snails and freshwater snails. The word snail without any qualifier is however more often...

s, terrestrial

Terrestrial animal

Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...

 pulmonate gastropod mollusks in the family Dyakiidae

Dyakiidae

Dyakiidae is a family of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Dyakioidea ....

.

The species within this genus are very difficult to identify from shells only, because the shells are all very similar.

Species

The genus Everettia included 15 species in 2007 but there was described additional 11 species of Everettia in northern Borneo

Borneo

Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....

 in 2009:

• Everettia corrugata Laidlaw, 1937
  • Everettia corrugata corrugata Laidlaw, 1937
  • Everettia corrugata williamsi Liew, Schilthuizen & Vermeulen, 2009
• Everettia dominiki Liew, Schilthuizen & Vermeulen, 2009
• Everettia interior Liew, Schilthuizen & Vermeulen, 2009
• Everettia jasilini Liew, Schilthuizen & Vermeulen, 2009
• Everettia jucunda (L. Pfeiffer, 1891) - the type species
  Type species
  In biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
  
  
• Everettia jucundior Liew, Schilthuizen & Vermeulen, 2009
• Everettia klemmantanica Gude, 1918
• Everettia lapidini Liew, Schilthuizen & Vermeulen, 2009
• Everettia layanglayang Liew, Schilthuizen & Vermeulen, 2009
• Everettia monticola Liew, Schilthuizen & Vermeulen, 2009
• Everettia occidentalis Liew, Schilthuizen & Vermeulen, 2009
• Everettia paulbasintali Liew, Schilthuizen & Vermeulen, 2009
• Everettia planispira Liew, Schilthuizen & Vermeulen, 2009
• Everettia safriei Liew, Schilthuizen & Vermeulen, 2009
• Everettia subconsul (Smith, 1887)
• Everettia themis (Smith, 1895)