What is the most poisonous starfish?

Answered by James Kissner

The crown-of-thorns starfish, scientifically known as Acanthaster planci, is considered one of the most poisonous starfish in the world. This species gets its name from the venomous thorn-like spines that cover its upper surface, resembling the biblical crown of thorns. These spines are a key characteristic of the crown-of-thorns starfish and play a role in its predatory behavior.

Belonging to the family Acanthasteridae and the genus Acanthaster, the crown-of-thorns starfish is one of the largest starfish species globally. It can grow up to a foot in diameter, and its body is covered in long, sharp spines that are typically colored in shades of brown, red, or purple.

The venom produced by the crown-of-thorns starfish is highly potent and can cause severe pain and discomfort if it comes into contact with human skin. The spines are hollow and connected to venom glands, allowing the starfish to inject venom into its prey or potential threats. The venom contains a mix of toxins, including neurotoxins, which affect the nervous system, and cytotoxins, which damage cells.

Encountering a crown-of-thorns starfish can be hazardous, as their spines can easily penetrate the skin and deliver their venom. The resulting symptoms can vary depending on the individual’s sensitivity to the venom and the amount injected. Common reactions include intense pain, swelling, redness, and inflammation around the affected area. In some cases, nausea, vomiting, muscle weakness, and dizziness may also occur. It is crucial to seek medical attention if stung by a crown-of-thorns starfish to ensure proper treatment and prevent potential complications.

The crown-of-thorns starfish is primarily found in the coral reefs of the Indo-Pacific region, including the Great Barrier Reef in Australia. Despite being venomous, these starfish are not aggressive towards humans and typically only sting when they feel threatened or are accidentally touched. However, their feeding habits can be destructive to coral reefs, as they primarily feed on coral polyps, which are essential for reef health and stability.

The population of crown-of-thorns starfish can experience outbreaks, where large numbers of these starfish gather and feed on coral extensively, causing significant damage to reef ecosystems. This phenomenon can have detrimental effects on the biodiversity and overall health of coral reefs.

Efforts are made to control outbreaks of crown-of-thorns starfish through various methods, including manual removal, chemical injections, and the introduction of natural predators, such as the Triton’s trumpet snail. However, managing these outbreaks remains a challenging task due to the starfish’s ability to reproduce rapidly, with each adult female producing millions of eggs during the breeding season.

The crown-of-thorns starfish, with its venomous spines and destructive feeding habits, is considered one of the most poisonous starfish species. Though potentially dangerous to humans, they primarily pose a threat to coral reefs, where they can cause significant damage during outbreaks. Understanding their behavior and implementing effective management strategies is crucial for maintaining the delicate balance of reef ecosystems.