Nudibranch
Nudibranchs (Order: Nudibranchia)
Scientific Classification:
- Kingdom: Animalia
- Phylum: Mollusca
- Class: Gastropoda
- Order: Nudibranchia
Types of Nudibranchs:
Nudibranchs are a diverse group with over 3,000 known species. They are classified into two main suborders:
Dorid Nudibranchs (Suborder: Doridina)
- Have a smooth, often rounded body with gill-like structures at the back.
- Examples: Chromodoris annae (Blue Dorid), Doris verrucosa.
Aeolid Nudibranchs (Suborder: Cladobranchia)
- Have cerata (finger-like appendages) on their backs, which store stinging cells from their prey.
- Examples: Glaucus atlanticus (Blue Dragon), Phyllodesmium longicirrum (Solar-Powered Nudibranch).
Habitat:
- Found in oceans worldwide, from shallow tropical reefs to deep-sea environments.
- Prefer coral reefs, rocky shores, kelp forests, and seagrass beds.
- Some deep-sea species exist at depths of over 2,500 meters.
Diet:
- Carnivorous, feeding on sponges, hydroids, corals, anemones, and even other nudibranchs.
- Some species absorb toxins or stinging cells from prey for self-defense.
- Certain species like Phyllodesmium are solar-powered and derive energy from algae in their tissues.
Lifespan:
- A few weeks to over a year, depending on species.
- Short-lived but continuously reproduce.
Sexual Differences (Hermaphroditism):
- Nudibranchs are simultaneous hermaphrodites, meaning they have both male and female reproductive organs.
- They exchange sperm with each other but cannot fertilize themselves.
How to Spot a Nudibranch:
- Bright, vivid colors – often in blues, oranges, purples, or reds.
- Soft-bodied with no shell, unlike other gastropods.
- Unique external structures:
- Dorid nudibranchs have feathery gills at the back.
- Aeolid nudibranchs have cerata (tentacle-like structures).
- Often crawling slowly on coral, rocks, or sand.
Countries Where Nudibranchs Are Found:
- Australia (Great Barrier Reef, Tasmania, Western Australia)
- Indonesia (Raja Ampat, Bali, Komodo)
- Philippines (Anilao, Tubbataha Reefs)
- Japan (Okinawa, Izu Peninsula)
- Hawaii & Pacific Islands
- Red Sea (Egypt, Sudan, Saudi Arabia)
- Madagascar, Mozambique, South Africa
- Caribbean & Mediterranean Seas