The lesser weever (''Echiichthys vipera'') is a venomous

weever Weevers (or weeverfish) are nine extant taxon, extant species of fishes of Family (biology), family Trachinidae, order Trachiniformes, part of the Percomorpha clade. They are long (up to 37 cm), mainly brown in color, and have venomous s ...

of the family Trachinidae, in the

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...

Perciformes, and the

class Class or The Class may refer to: Common uses not otherwise categorized * Class (biology), a taxonomic rank * Class (knowledge representation), a collection of individuals or objects * Class (philosophy), an analytical concept used differentl ...

Actinopterygii Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or h ...

. It is generally found on the sandy sea beds of the open sea, near the shore. Lesser weevers may sting

swimmers Swimming is the self-propulsion of a person through water, or other liquid, usually for recreation, sport, exercise, or survival. Locomotion is achieved through coordinated movement of the limbs and the body to achieve hydrodynamic thrust that r ...

badly if disturbed in the water, and fishermen when they clean their fishing nets. The lesser weever grows up to 18 cm long, but generally less than 15 cm, with an elongated body. Its color can be described as greyish-brown on the back and silvery-white on the sides. It has no spines in front of its eyes.

Habitat

Lesser weever fish occur in the eastern

Atlantic The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe an ...

from the

North Sea The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the Norwegian S ...

around the British Isles to

Morocco Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to ...

and

Madeira ) , anthem = ( en, "Anthem of the Autonomous Region of Madeira") , song_type = Regional anthem , image_map=EU-Portugal_with_Madeira_circled.svg , map_alt=Location of Madeira , map_caption=Location of Madeira , subdivision_type=Sovereign st ...

, and in the

Mediterranean The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the e ...

. It is typically found resting on the bottom, partially buried with its eyes and tip of the first dorsal fin exposed.

Biology

The lesser weever is

littoral The littoral zone or nearshore is the part of a sea, lake, or river that is close to the shore. In coastal ecology, the littoral zone includes the intertidal zone extending from the high water mark (which is rarely inundated), to coastal areas ...

and

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "t ...

, living on sandy, muddy bottoms, ranging from a few meters deep to 150 m (in winter). Resting on the bottom, its position can be described as with eyes buried and the tip of the first

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ...

exposed. Because of its

venom Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...

and its occurrence near beaches, it is considered to be one of Europe's most dangerous weever

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

. The

glands In animals, a gland is a group of cells in an animal's body that synthesizes substances (such as hormones) for release into the bloodstream (endocrine gland) or into cavities inside the body or its outer surface (exocrine gland). Structure De ...

are located on its first dorsal fin, which is completely black, and on the gill cover. This species has the most potent toxin of all the weevers. The venom contains a

cytolysin Cytolysin refers to the substance secreted by microorganisms, plants or animals that is specifically toxic to individual cells, in many cases causing their dissolution through lysis. Cytolysins that have a specific action for certain cells are n ...

, trachinine, as well as

serotonin Serotonin () or 5-hydroxytryptamine (5-HT) is a monoamine neurotransmitter. Its biological function is complex and multifaceted, modulating mood, cognition, reward, learning, memory, and numerous physiological processes such as vomiting and vas ...

histamine Histamine is an organic nitrogenous compound involved in local immune responses, as well as regulating physiological functions in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Since histamine was discovered in ...

-realising substances and various

enzymes Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different molecule ...

Effect on humans

The

sting Sting may refer to: * Stinger or sting, a structure of an animal to inject venom, or the injury produced by a stinger * Irritating hairs or prickles of a stinging plant, or the plant itself Fictional characters and entities * Sting (Middle-eart ...

of a weever causes acute and intense pain, which is frequently radiated to the area around the limb. The

pain Pain is a distressing feeling often caused by intense or damaging stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sensory and emotional experience associated with, or resembling that associated with, ...

intensity reaches its peak 30 minutes after the sting, and then slowly decreases, but some pain (or other sensation, such as a tingle) may continue to affect the area for up to 24 hours. Very rarely, pain can be propagated to the tributary

lymph nodes A lymph node, or lymph gland, is a kidney-shaped organ of the lymphatic system and the adaptive immune system. A large number of lymph nodes are linked throughout the body by the lymphatic vessels. They are major sites of lymphocytes that includ ...

, i.e. those in the groin (when the sting is on the sole of the foot), or those in the armpit (if the sting is on the hands). The best

first aid First aid is the first and immediate assistance given to any person with either a minor or serious illness or injury, with care provided to preserve life, prevent the condition from worsening, or to promote recovery. It includes initial in ...

is to wash the wound, and then to immerse it in very hot water for at least an hour, to ease the pain and help destroy the protein-based venom. Water temperature for immersion should be 40°C (104°F) or as hot as the patient can tolerate. Also, reassure the patient of the relative harmlessness of the sting.

References

* *

External links

More detailed Description

Other hazardous fish
{{Taxonbar, from=Q1470652 lesser weever Venomous fish Fish of the East Atlantic Fish of the Mediterranean Sea Fish of the North Sea Marine fish of Europe lesser weever Taxa named by Georges Cuvier

Habitat

Biology

Effect on humans

See also

References

External links