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

weever Weevers (or weeverfish) are nine extant species of ray-finned fishes of the family Trachinidae in the order Perciformes, part of the wider clade Percomorpha. They are long (up to 37 cm), mainly brown in color, and have venomous spines on ...

of the family Trachinidae, in the

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

Perciformes Perciformes (), also called the Acanthopteri, is an order or superorder of ray-finned fish in the clade Percomorpha. ''Perciformes'' means " perch-like". Among the well-known members of this group are perches and darters ( Percidae), and als ...

, and the

class Class, Classes, 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 d ...

Actinopterygii Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class (biology), class of Osteichthyes, bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built ...

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

swimmers Swimming is an individual or team racing sport that requires the use of one's entire body to move through water. The sport takes place in pools or open water (e.g., in a sea or lake). Competitive swimming is one of the most popular Olympic ...

badly if disturbed in the water, and

fishermen A fisherman or fisher is someone who captures fish and other animals from a body of water, or gathers shellfish. Worldwide, there are about 38 million commercial and subsistence fishers and fish farmers. Fishermen may be professional or recr ...

when they clean their

fishing net A fishing net or fish net is a net (device), net used for fishing. Fishing nets work by serving as an improvised fish trap, and some are indeed rigged as traps (e.g. #Fyke nets, fyke nets). They are usually wide open when deployed (e.g. by cast ...

s. 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 oceanic divisions, with an area of about . It covers approximately 17% of Earth's surface and about 24% of its water surface area. During the Age of Discovery, it was known for se ...

from the

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

around the British Isles to

Morocco Morocco, officially the Kingdom of Morocco, is a country in the Maghreb region of North Africa. It has coastlines on the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria to Algeria–Morocc ...

and

Madeira Madeira ( ; ), officially the Autonomous Region of Madeira (), is an autonomous Regions of Portugal, autonomous region of Portugal. It is an archipelago situated in the North Atlantic Ocean, in the region of Macaronesia, just under north of ...

, 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 east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

. 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, also called litoral 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 i ...

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 the Ancient Greek word (), meaning "the depths". ...

, 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 on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

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 A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

. The

glands A gland is a Cell (biology), cell or an Organ (biology), organ in an animal's body that produces and secretes different substances that the organism needs, either into the bloodstream or into a body cavity or outer surface. A gland may also funct ...

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 ...

, trachinine, as well as

serotonin Serotonin (), also known as 5-hydroxytryptamine (5-HT), is a monoamine neurotransmitter with a wide range of functions in both the central nervous system (CNS) and also peripheral tissues. It is involved in mood, cognition, reward, learning, ...

histamine Histamine is an organic nitrogenous compound involved in local immune responses communication, as well as regulating physiological functions in the gut and acting as a neurotransmitter for the brain, spinal cord, and uterus. Discovered in 19 ...

-realising substances and various

enzymes An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as pro ...

Effect on humans

The sting 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 Stimulus (physiology), stimuli. The International Association for the Study of Pain defines pain as "an unpleasant sense, sensory and emotional experience associated with, or res ...

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 (anatomy), 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 lymphoc ...

, 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). Common and minor symptoms include severe pain, itching, swelling, heat, redness, numbness, tingling, nausea, vomiting, joint aches, headaches, abdominal cramps, lightheadedness, increased urination and tremors. Rare and severe symptoms include abnormal heart rhythms, weakness, shortness of breath, seizures, decreased blood pressure,

gangrene Gangrene is a type of tissue death caused by a lack of blood supply. Symptoms may include a change in skin color to red or black, numbness, swelling, pain, skin breakdown, and coolness. The feet and hands are most commonly affected. If the ga ...

, tissue degeneration and unconsciousness.Branko Šuljić, ''Sportski ribolov'', 2001 The best

first aid First aid is the first and immediate assistance given to any person with a medical emergency, with care provided to preserve life, prevent the condition from worsening, or to promote recovery until medical services arrive. First aid is gener ...

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 The lesser weever (''Echiichthys vipera'') is a venomous weever of the family Trachinidae, in the order Perciformes, and the class Actinopterygii. It is generally found on the sandy sea beds of the open sea, near the shore. Lesser weevers may s ...

Venomous fish Fish of the East Atlantic Fish of the Mediterranean Sea Fish of the North Sea Marine fish of Europe

Taxa named by Georges Cuvier

Habitat

Biology

Effect on humans

See also

References

External links