The term snail is used to refer to a great diversity of animals from the group of gastropods, which belong to the Mollusca phylum, which are characterized by the presence of a remarkably visible external univalve shell. These animals have spread over a wide variety of habitats, including marine, freshwater and terrestrial, but even within each of them they can be distributed in different areas of the same ecosystem. A particular feature of snails is that they tend to have slow mobility, however, depending on the species, this does not prevent them from being able to move, dig, climb or swim.
Although they generally appear harmless, some are loaded with toxins that can be lethal, even to humans. Dare to continue reading this article on our site and learn about the types of poisonous snails
Characteristics of poisonous snails
There are not a few species of poisonous snails that exist, since it is estimated, in fact, that there are more than 10 thousand approximately. In this sense, they have a very wide diversity, which has made their taxonomy a not so simple situation. These animals are characterized by being marine predators and use their toxins to capture their prey and then devour them. For animals that have slow mobility, poison is undoubtedly a very advantageous strategy for the type of carnivorous diet they have.
One aspect that the various types of venomous snails have in common, despite the differences of each group, is that they all are included in the superfamily Conoidea, within which three have been identified, among others, that contain species with toxins: Conidae, Turridae and Terebridae.
Cone snails
Although there are other types of poisonous snails, the so-called cone snails are the only group where there are some species that can be lethal to humans. These animals belong to the Conidae family and it is specifically within the Conus genus that certain dangerous species are found.
These snails are characterized by not reaching large sizes, so they can measure around 23 cm in length However, Despite these dimensions and their slow movements, the attacks can be fast, which, together with the toxic substances they possess, make them one of the most dangerous snails out there and not only for us, but also for the species from which they are derived. they feed.
These are marine species that mainly inhabit tropical and subtropical waters, both in the Indian and Pacific oceans. They are not usually present in very deep areas; During the day they are usually located on living coral reefs or remnants of these, but at night they move to rocky or sandy areas.
Cone snails, unlike others, have the radula, their feeding apparatus, in a modified way, since they have pointed radular teeth and are also hollow. The aforementioned structures simulate a harpoon, which they use to inject the toxic substance, which has an effect on the victim's nervous and muscular system.
Characteristics of cone snail venom
The venom of these molluscs is made up of various peptides that are chains of amino acids, which have been called in this case as conotoxins o conopeptides, quite stable.
These conotoxins are smaller than the venom of other animal species, such as arachnids or snakes, a peculiarity that makes them spread more quickly after entering the body of the prey. This explains why the victim is paralyzed in just seconds But the most peculiar feature of these toxins is their degree of selectivity, so that they are able to select receptors at the cellular level to exert its powerful action in a much more effective way.
Examples of poisonous cone snails
To get to know them a little better, let's see below examples of poisonous snails belonging to this group:
- Geography cone snail (Conus geographus): also called cigarette snail, since it is said that a person stung by this animal, he only has time to smoke a cigarette before he dies. Indeed, it is one of the most poisonous species of snails. It is native to the tropical and subtropical waters of the Indian and Pacific Oceans, especially off the Australian coast. If you are interested in knowing more species, do not miss this other article where we show The most dangerous animals in Australia.
- Purple cone snail (Conus purpurascens): it is native to the Pacific Ocean, specifically inhabits off the Galapagos Islands and the Gulf of California. It does not exceed 7.5 cm and is purple in color, and can have different intensities, with black or brown patterns. It is also poisonous and could kill a person.
- Dall's cone snail (Conus dalli): is another species of poisonous snail with lethal potential in humans. It extends into the Pacific at great depths, for example, in the waters near the Galapagos Islands, the Gulf of California and Panama. Its coloration of yellow and brown tones simulates a network with triangular shapes.
In the image we can see the geographic cone snail.
Gemmula Snails
This is another type of poisonous snail found within the Turridae family, which has had some taxonomic divisions. It has a great variety of species and it is common to refer to these snails with the term 'turrids' or 'turridos'. However, it is specifically the snails of the Gemmula genus that present toxins used for hunting.
These snails are usually larger than the rest of the genera of the group and develop mainly in deep tropical waters of the oceans Indian and Pacific. The radula of this type of snail, once it causes the wound in the prey, releases the toxins it possesses. Their venom is made up of several disulfide-rich peptides, which have certain similarities to cone snail conotoxins.
Examples of Poisonous Gemmula Snails
As we have mentioned, only those belonging to the genus Gemmula have poisonous toxins, and here are some examples:
- Gemmula speciose: in English it is usually called splendid turrid, its shell is between 4 and 8 cm long and is characterized by its corrugated or carved form of white or yellowish color. It is distributed in the seas of China, Japan, the Philippines and Papua New Guinea, among others.
- Gemmula kieneri: its appearance is similar to G. speciose, in fact, it has an equal distribution range, although they also have a presence in Australia, at depths from 50 to a little over 300 meters. The size varies between 2.6 to 7 cm.
In the image we see the species Gemmula speciose.
Drill snails
This is the third group of poisonous snails that exist, which belong to the Terebridae family. They are also known as auger snails and their common names are associated with the coiled or spiral shape of their shell, which resembles the point of a drill. Not all terebrids are poisonous, some capture their prey and engulf it without using toxins. Those that do possess these compounds injure the victim with their hypodermic needle-shaped radular tooth, then proceed to inject the poison to immobilize it and finally devour it.
The venom of these animals, although it has certain similarities with the conotoxins in relation to their precursors, after they are formed, they present important divergences that allow establishing that there are no homologies between the venoms of cone snails and the family Terebridae.
Examples of poisonous drill snails
Since not all drill snails are poisonous, we mention two species that are:
- Terebra subulata: This species is distributed in East Africa, Madagascar, Japan, Hawaii and Australia, from 0 to 10 meters deep. It reaches lengths of up to about 11 cm, so it has an elongated shape, with a cream coloration and dark spots. Its venom is only effective against annelids on which it feeds, but harmless to vertebrates. Discover the annelids in this other post: "Types of annelids".
- Hastula hectica: known as 'beach auger', it is a dangerous and poisonous species of snail that measures between 3 and 8 cm, with a presence in the western Indian Ocean. Its toxin, as identified, differs from conotoxins.
Now that you know the most dangerous and poisonous snails in the world, don't stop discovering and visit this other article on the Types of marine and terrestrial snails.
In the photo we can see the beach auger snail.
