Conus - AbsoluteAstronomy.com

"Cucullus" redirects here. This may also refer to part of the clasper in male insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...

genitalia.

Conus is a large 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 small to large predatory 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, with the common names of cone snails, cone shells or cones. This genus is placed in the subfamily Coninae within the family Conidae. Geologically speaking, the genus is known from the Eocene

Eocene

The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...

to the Recent (Holocene

Holocene

The Holocene is a geological epoch which began at the end of the Pleistocene and continues to the present. The Holocene is part of the Quaternary period. Its name comes from the Greek words and , meaning "entirely recent"...

) periods. Conus species have shells that are shaped more or less like geometric cones

Cone (geometry)

A cone is an n-dimensional geometric shape that tapers smoothly from a base to a point called the apex or vertex. Formally, it is the solid figure formed by the locus of all straight line segments that join the apex to the base...

. Many species have colorful patterning on the shell surface. Conus snails are mostly tropical in distribution.

Conus snails are all venomous. Live ones should be handled with care or not handled at all, because they are all capable of "stinging" humans with unpleasant results. The species that are most dangerous to humans are the larger ones that prey on small bottom-dwelling fish. The other species hunt and eat marine worms or mollusks. Cone snails use a hypodermic-like modified radula

Radula

The radula is an anatomical structure that is used by molluscs for feeding, sometimes compared rather inaccurately to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus...

tooth and a poison gland to attack and paralyze their prey before engulfing it. The tooth is sometimes likened to a dart or a harpoon. It is barbed and can be extended some distance out from the mouth of the snail, at the end of the proboscis

Proboscis

A proboscis is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate. In simpler terms, a proboscis is the straw-like mouth found in several varieties of species.-Etymology:...

.

Cone snail venoms are mainly peptide

Peptide

Peptides are short polymers of amino acid monomers linked by peptide bonds. They are distinguished from proteins on the basis of size, typically containing less than 50 monomer units. The shortest peptides are dipeptides, consisting of two amino acids joined by a single peptide bond...

s. The venoms contain many different toxins that vary in their effects; some are extremely toxic. The sting of small cones is no worse than a bee sting, but the sting of a few of the larger species of tropical cone snails can be serious, occasionally even fatal to human beings. In recent years cone snail venom

Venom

Venom is the general term referring to any variety of toxins used by certain types of animals that inject it into their victims by the means of a bite or a sting...

is showing great promise as a source of new, medically important substances.

Distribution and habitat

There are over 600 different species of cone snails. This family is typically found in warm and tropical seas and oceans worldwide, and reaches its greatest diversity in the Western Indo-Pacific

Western Indo-Pacific

The Western Indo-Pacific is a biogeographic region of the Earth's seas, comprising the tropical waters of the eastern and central Indian Ocean. It is part of the larger Indo-Pacific, which includes the tropical Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in...

Region. However, some species of Conus are adapted to temperate environments, such as the Cape coast of South Africa, or the cool waters of southern California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

(Conus californicus
Conus californicus
Conus californicus, common name the California cone, is a species of small, predatory sea snail, a marine gastropod mollusk in the family Conidae, the cone snails.- Distribution :...

) and are endemic to these areas.

This genus is found in all tropical and subtropical seas from tidal waters to deeper areas, living on sand or among rocks or coral reefs. When living on sand, these snails will bury themselves with only the siphon protruding from the surface. Many tropical cone snails live in or near coral reef

Coral reef

Coral reefs are underwater structures made from calcium carbonate secreted by corals. Coral reefs are colonies of tiny living animals found in marine waters that contain few nutrients. Most coral reefs are built from stony corals, which in turn consist of polyps that cluster in groups. The polyps...

s. Some species are found under rocks in the lower intertidal and shallow subtidal zones.

Shell description

This genus shows a large variety of colors and patterns, and local varieties and color forms of the same species often occur. This has led to the creation of a large number of known synonyms and probable synonyms, making it difficult to give an exact taxonomic assignment for many snails in this genus. As of 2009, more than 3,200 different species names have been assigned to snails in the genus Conus, with an average of 16 new species names introduced a year.

The shells

Gastropod shell

The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...

of Conus species are small to large in size. The shells are shaped more or less like the geometric shape known as a cone, as one might expect from the popular and scientific name. The shell is many-whorled and in the form of an inverted cone, the anterior end being the narrow end. The protruding parts of the top of the whorl

Whorl (mollusc)

A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in of numerous gastropods, but it is also found in shelled cephalopods including Nautilus, Spirula and the large extinct subclass of cephalopods known as the...

s that form the sprire

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...

are more or less in the shape of another, much more flattened, cone. The 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....

is elongated and narrow. The horny operculum

Operculum (gastropod)

The operculum, meaning little lid, is a corneous or calcareous anatomical structure which exists in many groups of sea snails and freshwater snails, and also in a few groups of land snails...

is very small. The outer lip is simple, thin and sharp and without a callus. The outer lip has a notched tip at the upper part. The columella is straight.

The larger species of cone snails can grow up to 23 cm in length. The shells of cone snails are often brightly colored, and have interesting patterns, although in some species the color patterns may be partially or completely hidden under an opaque layer of periostracum

Periostracum

The periostracum is a thin organic coating or "skin" which is the outermost layer of the shell of many shelled animals, including mollusks and brachiopods. Among mollusks it is primarily seen in snails and clams, i.e. in bivalves and gastropods, but it is also found in cephalopods such as the...

. The patterns on the shell sometimes resemble certain one-dimensional cellular automata, and may in fact be biological versions of them.

The shell of living species is covered with a thin periostracum

Periostracum

, a transparent yellowish or brownish membrane.

Life habits

Cone snails are carnivorous

Carnivore

A carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging...

, and predatory. They hunt and eat prey such as marine worm

Worm

The term worm refers to an obsolete taxon used by Carolus Linnaeus and Jean-Baptiste Lamarck for all non-arthropod invertebrate animals, and stems from the Old English word wyrm. Currently it is used to describe many different distantly-related animals that typically have a long cylindrical...

s, small fish

Fish

Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...

, mollusks, and even other cone snails. Because cone snails are slow-moving, they use a venomous harpoon

Harpoon

A harpoon is a long spear-like instrument used in fishing to catch fish or large marine mammals such as whales. It accomplishes this task by impaling the target animal, allowing the fishermen to use a rope or chain attached to the butt of the projectile to catch the animal...

(called a toxoglossan radula

Radula

) to capture faster-moving prey such as fish. The venom of a few larger species, especially the piscivorous ones, is powerful enough to kill a human being.

The osphradium

Osphradium

The osphradium is the olfactory organ in certain molluscs, linked with the respiration organ.The main function of this is to test incoming water for silt and other possible food particles.It is used by all members of the Genus Conus....

(a chemoreceptory organ) in the family Conidae is more highly specialized than the same organ in any other family of gastropods. It is through this sensory modality that cone snails become aware of the presence of a prey animal, not through vision. The cone snails immobilize their prey using a modified, dartlike, barbed radula

Radula

r tooth, made of chitin

Chitin

Chitin n is a long-chain polymer of a N-acetylglucosamine, a derivative of glucose, and is found in many places throughout the natural world...

, along with a poison gland containing neurotoxin

Neurotoxin

A neurotoxin is a toxin that acts specifically on nerve cells , usually by interacting with membrane proteins such as ion channels. Some sources are more general, and define the effect of neurotoxins as occurring at nerve tissue...

s. Small species of these cone snails hunt small prey such as marine worms, whereas larger cone snails hunt live fish.

Molecular phylogeny

Molecular phylogeny

Molecular phylogenetics is the analysis of hereditary molecular differences, mainly in DNA sequences, to gain information on an organism's evolutionary relationships. The result of a molecular phylogenetic analysis is expressed in a phylogenetic tree...

research by Kraus et al. (2010) based on a part of "intron

Intron

An intron is any nucleotide sequence within a gene that is removed by RNA splicing to generate the final mature RNA product of a gene. The term intron refers to both the DNA sequence within a gene, and the corresponding sequence in RNA transcripts. Sequences that are joined together in the final...

9" of the gamma-glutamyl carboxylase

Gamma-glutamyl carboxylase

Gamma-glutamyl carboxylase is an enzyme that in humans is encoded by the GGCX gene, located on chromosome 2 at 2p12.-Function:Gamma-glutamyl carboxylase is an enzyme that catalyzes the posttranslational modification of vitamin K-dependent proteins...

gene has shown that feeding on fish in Conus has evolved at least twice independently.

Harpoon and venoms

Cone snails use a radula

Radula

tooth as a harpoon-like structure for predation

Predation

In ecology, predation describes a biological interaction where a predator feeds on its prey . Predators may or may not kill their prey prior to feeding on them, but the act of predation always results in the death of its prey and the eventual absorption of the prey's tissue through consumption...

. Each of these harpoons is a modified tooth, primarily made of chitin

Chitin

Chitin n is a long-chain polymer of a N-acetylglucosamine, a derivative of glucose, and is found in many places throughout the natural world...

and formed inside the mouth of the snail, in a structure known as the radula. (The radula in most gastropods has rows of many small teeth, and is used for grasping at food and scraping it into the mouth.) Each specialized cone snail tooth is stored in the radula sac (an evaginated pocket in the posterior wall of the buccal cavity), except the tooth that is currently ready to be used.

The tooth is hollow and barbed, and is attached to the tip of the radula in the radular sac, inside the snail's throat. When the snail detects a prey animal nearby, it extends a long flexible tube called a proboscis

Proboscis

towards the prey. The radula tooth is loaded with venom from the poison bulb and, still attached to the radula, is fired from the proboscis into the prey by a powerful muscular contraction. The venom paralyzes small fish almost instantly. The snail then retracts the radula, drawing the subdued prey into the mouth. After the prey has been digested, the cone snail will regurgitate any indigestible material such as spines and scales, along with the then-disposable harpoon. There is always a dart stored in the radular sac. A dart may be used in self-defense when the snail feels threatened.

The tropical cone snail Conus purpurascens
Conus purpurascens
Conus purpurascens is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.Like all species within the genus Conus, these snails are predatory and venomous. They are capable of "stinging" humans, therefore live ones should be handled carefully...

uses its special modified radular teeth to fire a retrievable hollow dart at small fish and inject a toxin. The toxin rapidly paralyses the fish, which the cone snail then swallows.

All cone snail species are equipped with a battery of toxic harpoons which can fire in any direction, even backwards. Some of these toxins can be fatal to humans.

The venom of cone snails contains hundreds of different compounds, and its exact composition varies widely from one species of cone snail to another. The toxins in these various venoms are called conotoxin

Conotoxin

A conotoxin is one of a group of neurotoxic peptides isolated from the venom of the marine cone snail, genus Conus.Conotoxins, which are peptides consisting of 10 to 30 amino acid residues, typically have one or more disulfide bonds. Conotoxins have a variety of mechanisms of actions, most of...

s. These are various peptide

Peptide

s, each targeting a specific nerve channel or receptor. Some cone snail venoms also contain a pain-reducing toxin, which the snail uses to pacify the victim before immobilising and then killing it.

Risk of being stung

The bright colors and patterns of cone snails are attractive to the eye, and therefore people sometimes pick up the live animals and hold them in their hand for a while. This is risky, because the snail often fires its harpoon in these situations. In the case of the larger species of cone snail, the harpoon is sometimes capable of penetrating the skin, even through glove

Glove

A glove is a garment covering the hand. Gloves have separate sheaths or openings for each finger and the thumb; if there is an opening but no covering sheath for each finger they are called "fingerless gloves". Fingerless gloves with one large opening rather than individual openings for each...

s or wetsuit

Wetsuit

A wetsuit is a garment, usually made of foamed neoprene, which is worn by surfers, divers, windsurfers, canoeists, and others engaged in water sports, providing thermal insulation, abrasion resistance and buoyancy. The insulation properties depend on bubbles of gas enclosed within the material,...

s.

The sting of many of the smallest cone species may be no worse than that of a bee or hornet sting, but in the case of a few of the larger tropical fish-eating species, especially Conus geographus
Conus geographus
Cnous geographus, common name the geography cone, is a species of predatory sea snail, a marine gastropod mollusk in the family Conidae, the cone snails, cone shells or cones. Although all cone snails hunt and kill prey using venom, the venom of this species is known to be especially potent...

, Conus tulipa
Conus tulipa
Conus tulipa is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.Like all species within the genus Conus, these snails are predatory and venomous...

and Conus striatus
Conus striatus
Conus striatus, common name the striated cone, is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.These snails are predatory and venomous...

, a sting can sometimes have fatal consequences. Other dangerous species are Conus pennaceus
Conus pennaceus
Conus pennaceus, common name the feathered cone, is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.Like all species within the genus Conus, these snails are predatory and venomous...

, Conus textile
Conus textile
Conus textile, common name the cloth of gold cone is a venomous species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails, cone shells or cones. The species is extremely dangerous to humans.-Distribution:C...

, Conus aulicus
Conus aulicus
Conus aulicus, common name the princely cone, is a species of a predatory sea snail, a marine gastropod mollusk in the family Conidae, the cone snails, cone shells or cones.-Description:...

, Conus magus
Conus magus
Conus magus, common name the magical cone, is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.Like all species within the genus Conus, these snails are predatory and venomous...

and Conus marmoreus
Conus marmoreus
Conus marmoreus, common name the "marbled cone", is a species of predatory sea snail, a marine gastropod mollusk in the family Conidae, the cone snails, cone shells or cones. This is a species which is believed to feed mostly on marine molluscs including other cone snails. This snail is venomous,...

http://pagesperso-orange.fr/zonatus/Killers%20cones.htm. According to Goldfrank's Toxicologic Emergencies, only about 15 deaths can be confidently attributed to cone snail envenomation.

Most of the cone snails that hunt worms rather than fish are probably not a real risk to humans, with the possible exception of larger species such as Conus vexillum
Conus vexillum
Conus vexillum, common name the vexillum cone, is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies....

or Conus quercinus
Conus quercinus
Conus quercinus is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.Like all species within the genus Conus, these snails are predatory and venomous. They are capable of "stinging" humans, therefore live ones should be handled carefully or...

.

One of the fish-eating species, the geography cone, Conus geographus, is also known colloquially as the "cigarette snail," a humorous exaggeration implying that, when stung by this creature, the victim will have only enough time to smoke a cigarette before dying.

Symptoms of a more serious cone snail sting include intense, localized pain

Pain

Pain is an unpleasant sensation often caused by intense or damaging stimuli such as stubbing a toe, burning a finger, putting iodine on a cut, and bumping the "funny bone."...

, swelling, numbness and tingling and vomiting. Symptoms can start immediately or can be delayed in onset for days. Severe cases involve muscle paralysis

Paralysis

Paralysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling in the affected area if there is sensory damage as well as motor. A study conducted by the Christopher & Dana Reeve Foundation, suggests that about 1 in 50 people have been diagnosed...

, changes in vision

Visual perception

Visual perception is the ability to interpret information and surroundings from the effects of visible light reaching the eye. The resulting perception is also known as eyesight, sight, or vision...

and respiratory failure

Respiratory failure

The term respiratory failure, in medicine, is used to describe inadequate gas exchange by the respiratory system, with the result that arterial oxygen and/or carbon dioxide levels cannot be maintained within their normal ranges. A drop in blood oxygenation is known as hypoxemia; a rise in arterial...

that can lead to death

Death

Death is the permanent termination of the biological functions that sustain a living organism. Phenomena which commonly bring about death include old age, predation, malnutrition, disease, and accidents or trauma resulting in terminal injury....

. There is no antivenom, and treatment involves providing life support

Life support

Life support, in medicine is a broad term that applies to any therapy used to sustain a patient's life while they are critically ill or injured. There are many therapies and techniques that may be used by clinicians to achieve the goal of sustaining life...

until the venom is metabolised by the victim.

Medical use of the venom

See also: Conantokins

Conantokins

Conantokins are a small family of helical peptides, rich in γ-carboxyglutamate amino acid residues. They are derived from the venom of predatory marine snails of the genus Conus. Conantokins act as potent and specific antagonists of the N-methyl-D-aspartate receptor . They are the only...

, Conotoxin

Conotoxin

The appeal of the cone snail's venom for creating pharmaceutical drugs is the precision and speed with which the various components act; many of the compounds target a particular class of receptor, to the exclusion of any other. This means that in isolation, they can reliably and quickly produce a particular effect on the body's systems without side effects; for example, almost instantly reducing heart rate or turning off the signaling of a single class of nerve, such as pain receptors.

The venom of some cone snails, such as the magician cone, Conus magus
Conus magus
Conus magus, common name the magical cone, is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.Like all species within the genus Conus, these snails are predatory and venomous...

, shows much promise for providing a non-addictive pain reliever 1000 times as powerful as, and possibly a replacement for, morphine

Morphine

Morphine is a potent opiate analgesic medication and is considered to be the prototypical opioid. It was first isolated in 1804 by Friedrich Sertürner, first distributed by same in 1817, and first commercially sold by Merck in 1827, which at the time was a single small chemists' shop. It was more...

.

Many peptides produced by the cone snails show prospects for being potent pharmaceuticals, such as AVC1, isolated from the Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

n species, the Queen Victoria cone, Conus victoriae
Conus victoriae
Conus victoriae is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails and their allies.Like all species within the genus Conus, these snails are predatory and venomous...

. This has proved very effective in treating postsurgical and neuropathic pain, even accelerating recovery from nerve injury

Nerve injury

Nerve injury is injury to nervous tissue. There is no single classification system that can describe all the many variations of nerve injury. Most systems attempt to correlate the degree of injury with symptoms, pathology and prognosis...

.

The first painkiller derived from cone snail toxins, ziconotide, was approved by the U.S. Food and Drug Administration

Food and Drug Administration

The Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...

in December 2004 under the name "Prialt". Other drugs are in clinical and preclinical trials, such as compounds of the toxin that may be used in the treatment of Alzheimer's disease

Alzheimer's disease

Alzheimer's disease also known in medical literature as Alzheimer disease is the most common form of dementia. There is no cure for the disease, which worsens as it progresses, and eventually leads to death...

, Parkinson's disease

Parkinson's disease

Parkinson's disease is a degenerative disorder of the central nervous system...

, and epilepsy

Epilepsy

Epilepsy is a common chronic neurological disorder characterized by seizures. These seizures are transient signs and/or symptoms of abnormal, excessive or hypersynchronous neuronal activity in the brain.About 50 million people worldwide have epilepsy, and nearly two out of every three new cases...

Shell collecting

The intricate color patterns of cones have made them one of the most popular collectible shells

Conchology

Conchology is the scientific or amateur study of mollusc shells. Conchology is one aspect of malacology, the study of molluscs, however malacology studies molluscs as whole organisms, not just their shells. Conchology pre-dated malacology as a field of study. It includes the study of land and...

.

Conus gloriamaris
Conus gloriamaris
Conus gloriamaris, common name the Glory of the Seas Cone, is a species of sea snail, a marine gastropod mollusk in the family Conidae, the cone snails, cone shells or cones. It is commonly found in the Pacific and Indian Oceans....

, the "Glory of the Seas" cone was, in earlier centuries, one of the most famous and sought-after seashells, with only a few specimens in private collections. This apparent rarity meant that shells of this species fetched very high prices, until finally the habitat for this cone was discovered. Sizable populations were then located, and this brought the price down dramatically.

As jewelry

Naturally-occurring, beachworn cone shell "tops" (the broken-off spire of the shell, which usually end up with a hole worn at the tip) can function as beads without any further modification. In Hawaii

Hawaii

Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...

, these natural beads were traditionally collected from the beach drift to make puka shell

Puka shell

Puka shells originally were naturally occurring bead-like objects which could be found on some beaches in Hawaii. These were beachworn pieces of cone snail shells, a kind of seashell. Puka is the Hawaiian word for "hole" and refers to the naturally occurring hole in the middle of these rounded...

jewelry. Since it is hard to obtain enough naturally-occurring cone tops, almost all modern puka shell jewelry uses cheaper imitations, cut from thin shells of other species of mollusk, or even made of plastic.

Species

The number of valid names of recent species in the genus Conus is over 600 and there are, in addition, a large number of fossil species.

Prior to 2009, all species within the family Conidae were still placed in one genus Conus
Conus
Conus is a large genus of small to large predatory sea snails, marine gastropod molluscs, with the common names of cone snails, cone shells or cones. This genus is placed in the subfamily Coninae within the family Conidae. Geologically speaking, the genus is known from the Eocene to the Recent ...

. Testing in order to try to understand the molecular phylogeny

Molecular phylogeny

of the Conidae was initially begun by Christopher Meyer and Alan Kohn, and is continuing, particularly with the advent of nuclear DNA testing in addition to mDNA testing.
In 2009, J.K. Tucker and M.J. Tenorio proposed a classification system consisting of 3 distinct families and 82 genera for the living species of cone snails. This classification was based upon shell

Gastropod shell

morphology

Morphology (biology)

In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....

, radular

Radula

differences, anatomy

Anatomy

Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...

, physiology

Physiology

Physiology is the science of the function of living systems. This includes how organisms, organ systems, organs, cells, and bio-molecules carry out the chemical or physical functions that exist in a living system. The highest honor awarded in physiology is the Nobel Prize in Physiology or...

, cladistics

Cladistics

Cladistics is a method of classifying species of organisms into groups called clades, which consist of an ancestor organism and all its descendants . For example, birds, dinosaurs, crocodiles, and all descendants of their most recent common ancestor form a clade...

, with comparisons to molecular (DNA) studies. Published accounts of genera within the Conidae that use these new genera include J.K. Tucker & M.J. Tenorio (2009), and Bouchet et al. (2011).

Some experts however currently (2011) prefer to keep using the traditional classification, where all species are placed in Conus
Conus
Conus is a large genus of small to large predatory sea snails, marine gastropod molluscs, with the common names of cone snails, cone shells or cones. This genus is placed in the subfamily Coninae within the family Conidae. Geologically speaking, the genus is known from the Eocene to the Recent ...

within the single family Conidae: for example, according to the current November 2011 version of the World Register of Marine Species

World Register of Marine Species

The World Register of Marine Species is a database that hopes to provide an authoritative and comprehensive list of names of marine organisms. The content of the registry is edited and maintained by scientific specialists on each group of organism. These taxonomists control the quality of the...

, all species within the family Conidae are in the genus Conus
Conus
Conus is a large genus of small to large predatory sea snails, marine gastropod molluscs, with the common names of cone snails, cone shells or cones. This genus is placed in the subfamily Coninae within the family Conidae. Geologically speaking, the genus is known from the Eocene to the Recent ...

. The binomial names of species in the 82 cone snail genera listed in Tucker & Tenorio 2009 are recognized by the World Register of Marine Species

World Register of Marine Species

as "alternative representations." Debate within the scientific community regarding this issue continues, and additional molecular phylogeny

Molecular phylogeny

studies are being carried out in an attempt to clarify the issue.

External links

Tucker J.K. (2009). Recent cone species database. September 4th 2009 Edition
Filmer R.M. (2001). A Catalogue of Nomenclature and Taxonomy in the Living Conidae 1758 - 1998. Backhuys Publishers, Leiden. 388pp
Bouchet, P.; Fontaine, B. (2009). List of new marine species described between 2002-2006. Census of Marine Life.
Natural History Museum Rotterdam - photos of Conus shells
Cone snail and conotoxins page
The Conus Biodiversity website
ConoServer
Conidae from worldwide.conchology.com. Scroll down for many photographs.
Pain-killer comes out of its shell (The Age news article)
Venomous snails aid medical science (BBC News Article).
ConeShell Collection Giancarlo Paganelli
Cone Snail Video - Hunting Footage and Physiology
Deadly Critters That Might Save Your Life (CNN)
iBioSeminar on Conus Peptides on-line lecture by Baldomero Olivera
Baldomero Olivera
Baldomero Olivera is a Filipino American chemist known for discovery of many cone snail toxins important for neuroscience. These molecules, called conotoxins led to a breakthrough in the study of ion channels and neuro-muscular synapses....
Zonatus Gallery http://mollus.oxfordjournals.org/content/55/2/167.short

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Distribution and habitat

Shell description

Life habits

Harpoon and venoms

Risk of being stung

Medical use of the venom

Shell collecting

As jewelry

Species

Further reading

External links