Milleporidae
Milleporidae is a family of colonial cnidarians, commonly referred to as fire corals. Despite their name, they are not true corals (Scleractinia), but rather a group of hydrozoans closely related to jellyfish. Fire corals are characterized by their hard, calcareous skeletons and their stinging nematocysts, which can cause painful burns to humans. They are widespread throughout tropical and subtropical waters, playing a vital role in coral reef ecosystems.
Common Names
Milleporidae are commonly known as fire corals, due to the painful sting they inflict. Other names include "stinging coral," "fire polyps," and "stony hydrocorals." The term "hydrocoral" is often used to describe Milleporidae and other closely related cnidarians that share similar characteristics, such as their hard, calcareous skeletons.
Characteristics
Milleporidae are characterized by the following features:
- Colonial: Fire corals form colonies of interconnected polyps, resembling a small, branching coral.
- Calcareous Skeleton: The polyps secrete a hard, calcium carbonate skeleton that provides structural support and protection.
- Stinging Nematocysts: Like other cnidarians, fire corals possess stinging cells called nematocysts. These cells contain barbed, toxic threads that are ejected upon contact, causing a painful burn.
- Polyp Morphology: The polyps are small, typically less than a millimeter in diameter, and are arranged in a complex network of interconnected tubes and chambers.
- Reproductive Strategies: Fire corals reproduce both sexually and asexually. Sexual reproduction involves the release of sperm and eggs, while asexual reproduction occurs through budding, where new polyps are generated from existing ones.
- Diverse Coloration: Fire corals can exhibit a variety of colors, including yellow, orange, brown, pink, and red. Their coloration is influenced by factors such as light intensity, water depth, and algal symbionts.
Environments
Fire corals are found in tropical and subtropical waters worldwide, typically in shallow, clear, and sunlit environments. They prefer habitats with strong currents, as these currents provide them with food and oxygen. They are commonly found in coral reefs, lagoons, and rocky shores.