thumb|Reef stonefish in the [[Great Barrier Reef Marine Park|239x239px]]

Synanceia verrucosa, the reef stonefish, is a species of venomous, marine ray-finned fish, belonging to the subfamily Synanceiinae, which is classified as being within the family Scorpaenidae, the scorpionfishes and their relatives. It is the most widespread species of stonefish, mostly found in shallow waters of the Red Sea and the Indo-Pacific. It possesses highly effective venom that can kill humans. It is the type species of Synanceia.

Taxonomy

Synanceia verrucosa was first formally described in 1801 by the German naturalists Marcus Elieser Bloch and Johann Gottlob Theaenus Schneider with the type locality given as India. Bloch and Schneider described a new genus, Synanceia, for this species, but in 1856 Eugène Anselme Sébastien Léon Desmarest designated Scorpaena horrida which had been described by Carl Linnaeus in 1766, as the type species of Synanceia. The specific name verrucosa means "covered with verrucas or warts", an allusion to the warty growths all over its body.

Description

Synanceia verrucosa are usually brown or grey, and may have areas of yellow, orange, or red.

The dorsal fin contains between 12 and 14 spines and 5 and 7 soft rays while the anal fin has 3 spines and 5 or 6 soft rays. This species reaches a maximum recorded total length of but is more typical. It has since been observed in Turkey, Lebanon, Syria and Israel.

This fish lives in coral reefs. It may settle on and around rocks and plants, or rest on the seabed.

thumb|Reef stonefish on the reef floor

The reef stonefish has evolved many adaptations to help them succeed in the reef bottom. Their skin texture and color is highly irregular which helps them hide and remain camouflaged when among rocks and corals.

Human uses

The primary commercial significance of this stonefish is as an aquarium pet. It is also sold for meat in Southern China markets. It is consumed in the Philippines, especially in Chinese restaurants, and in Japan.

Toxicity

thumb|Synanceia verrucosa in a public aquarium

The reef stonefish is the most venomous fish in the world. Stonefish venom can be fatal at a dose of only 18 mg, which the fish is capable of releasing with only six of its thirteen spines. The protein makeup differs between the three species of stonefish, but in reef stonefish the fatal protein is the verrucotoxin protein.

Effects of the venom include severe pain, shock, paralysis, and tissue death. Surviving victims may have nerve damage, which can lead to local muscle atrophy.

The venom consists of a mixture of proteins, including the hemolytic stonustoxin, the proteinaceous verrucotoxin, and the cardiotoxic cardioleputin.

Reproduction

The reef stonefish lives most of its life as a solitary animal, and during mating season only aggregates with the opposite sex for a short time. When a female stonefish has reached sexual maturity, she will lay her unfertilized eggs on the floor of the reef. A male will then swim by and release sperm onto the layer of eggs, fertilizing them. Stonefish eggs are fairly large, with young fish hatching well developed. The mating system of the reef stonefish is promiscuity, as the female will not discriminate between which males can lay their sperm on the egg layer. Sexual dimorphism is apparent in reef stonefish, with females being larger than males.

References

  • Synanceia verrucosa. Integrated Taxonomic Information System.