Scorpaenidae, the scorpionfish, are a 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...

 of mostly marine

Ocean

An ocean is a major body of saline water, and a principal component of the hydrosphere. Approximately 71% of the Earth's surface is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas.More than half of this area is over 3,000...

 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...

 that includes many of the world's most venomous species. As the name suggests, scorpionfish have a type of "sting" in the form of sharp spines coated with venomous mucus

Mucus

In vertebrates, mucus is a slippery secretion produced by, and covering, mucous membranes. Mucous fluid is typically produced from mucous cells found in mucous glands. Mucous cells secrete products that are rich in glycoproteins and water. Mucous fluid may also originate from mixed glands, which...

. The family is a large one, with hundreds of members. They are widespread in tropical and temperate seas, but mostly found in the Indo-Pacific

Indo-Pacific

The Indo-Pacific is a biogeographic region of the Earth's seas, comprising the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the seas connecting the two in the general area of Indonesia...

. They should not be confused with the cabezone

Cabezone

The Cabezon or also commonly referred to as the mother-in-law fish to Floridians, Scorpaenichthys marmoratus, is a sculpin native to the Pacific and Atlantic coasts of North America...

s, of the genus Scorpaenichthys, which belong to a separate, though related family, Cottidae

Cottidae

The Cottidae is a family of demersal fish in the order Scorpaeniformes, suborder Cottoidei . There are about 300 species in 70 genera of Cottidae that are mostly marine and found in shallow coastal waters in the northern and arctic regions...

.
Some types, such as the lionfish

Lionfish

Lionfish may refer to:* genus Pterois, collectively known as the lionfish* Red Lionfish , a significant invasive species off the East Coast of North America and in the Caribbean-Fish:...

, are attractive as well as dangerous, and highly desired for aquaria

Aquarium

An aquarium is a vivarium consisting of at least one transparent side in which water-dwelling plants or animals are kept. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, marine mammals, turtles, and aquatic plants...

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