Hazardous Marine Life – The ‘Demon Stinger’. (Inimicus Sp.)

Inimicus is a genus of venomous fishes, closely related to the true stonefishes.  These benthic fishes are found on sandy or siltysubstrates of lagoon and seaward reefs, in coastal regions of tropical oceans. They are collectively known by various common names, including Bearded GhoulSea GoblinSpiny Devilfish, Devil Stinger, Indian Walkman and Stingfish.

Lifestyle and peculiar habits

Demon Stinger is an ambush predators. They are nocturnal and typically lie partially buried on the sea floor during the day, covering themselves with sand and other debris to further camouflage themselves. They have no known natural predators. Once hidden, they are very reluctant to leave their refuge.

When threatened, they spread their brilliantly colored pectoral and caudal fins as a warning. On those occasions when a scuba diver does see them move, the Demon Stinger will display an unusual mechanism of subcarangiform locomotion—they crawl slowly along the seabed, employing the four lower rays (two on each side) of their pectoral fins as legs.

Venom Spines

All Demon Stinger possess a complex and extremely potent venom. It is stored in glands at the bases of needle-like spines in their dorsal fins. Upon contact with the dorsal fin, the fish can deliver a very painful, potentially fatal, sting.

The venom consists of a mixture of proteolytic enzymes, including stonustoxin (a hemotoxin), trachynilysin (a neurotoxin), and cardioleputin (a cardiotoxin). 

Envenomation results severe and immediate local pain, sometimes followed by shock, paralysis, tissue necrosis, and even death.

Treatment for Stings

Envenomation by a Demon Stinger is characterized by immediate and severe local pain. Medical aid must be sought at the earliest opportunity after envenomation.

Recommended first aid treatment includes immersion of the affected area in hot water. Immersing the injured area in water at a temperature of at least 45 °C (113 °F) can partially denature the proteolytic enzymes in the venom.

Some relief can also be obtained by infiltrating the envenomation site with a local anesthetic. For more extreme cases, an intramuscular injection of a specific horse-derived antivenom can be lifesaving.

Tetanus toxoid vaccine should also be administered, if indicated.

Surviving victims often suffer localized tissue necrosis and nerve damage, leading to atrophy of adjoining muscle tissues.

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