Ranella 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 very large warm-water and tropical sea snail

Sea snail

Sea snail is a common name for those snails that normally live in saltwater, marine gastropod molluscs....

s, marine

Marine (ocean)

Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 gastropod molluscs in the family

Family (biology)

In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Ranellidae

Ranellidae

Ranellidae, common name the triton shells or tritons, is a taxonomic family of small to very large predatory sea snails, marine gastropod mollusks in the clade Littorinimorpha.-Subfamilies:...

, the tritons.

Shell description

The shells of species within this genus are very large and solid, with a tall spire

Spire (mollusc)

A spire is a descriptive term for part of the coiled shell of mollusks. The word is a convenient aid in describing shells, but it does not refer to a very precise part of shell anatomy: the spire consists of all of the whorls except for the body whorl...

, a rounded aperture

Aperture (mollusc)

The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where part of the body of the animal emerges for locomotion, feeding, etc....

, a broadly flanged outer lip, and a moderately long siphonal canal

Siphonal canal

Some sea marine gastropods have a soft tubular anterior extension of the mantle called a siphon through which water is drawn into the mantle cavity and over the gill and which serves as a chemoreceptor to locate food. In many carnivorous snails, where the siphon is particularly long, the structure...

, which is flexed and inclined to the left. The varices

Varix (mollusc)

A varix is an anatomical feature of the shell of certain sea snails, marine gastropod molluscs.It is a thickened axial ridge in the shell of some families of gastropods. A varix is located at intervals around the whorl, and is formed by considerable thickening of the outer lip at a resting stage...

 are prominent and rounded, but are hollowed out on the inside.

Species

• Ranella olearium Linnaeus, 1758
• Ranella parthenopaeum Salis
  Carl Ulisses von Salis-Marschlins
  Carl Ulisses von Salis-Marschlins or Karl or Charles was a Swiss naturalist interested in botany , entomology, and conchology....
  
  , 1793. NOTE: this may no longer be considered a Ranella, this may in fact be an out of date name for Cymatium parthenopeum (Salis
  Carl Ulisses von Salis-Marschlins
  Carl Ulisses von Salis-Marschlins or Karl or Charles was a Swiss naturalist interested in botany , entomology, and conchology....
  
  , 1793)
• Ranella australasia
  Ranella australasia
  Ranella australasia is a species of predatory sea snail, a marine gastropod mollusk in the family Ranellidae, the triton snails, triton shells or tritons....
  
  (Perry, 1811)

Further reading

• R.Tucker Abbott & S. Peter Dance, 1982, Compendium of Seashells, Duttin, New York
  New York
  New York is a state in the Northeastern region of the United States. It is the nation's third most populous state. New York is bordered by New Jersey and Pennsylvania to the south, and by Connecticut, Massachusetts and Vermont to the east...