Scuba Steve's Dive Travel

The last post on my Romblon trip. It was memorable and I will be back.

Marionia arborescens – The Master of Disguise

Blending seamlessly into soft coral forests, Marionia arborescens is one of the ocean’s most underrated camouflage experts. With its tree-like branching body and soft, earthy tones, this nudibranch doesn’t just live on coral… it becomes it.

Often spotted at night, this species creeps across reefs feeding quietly while staying almost invisible to predators

Interesting Facts:

Coral mimic
Its branching gills and textured body closely resemble soft corals like Xenia, making it extremely hard to spot.

Night feeder
Like many in the Marionia genus, it’s mostly nocturnal—emerging after dark to feed on soft corals.

Tree-like anatomy
The name arborescens literally means “tree-like,” referring to its branching, bushy structures along the body.

Soft coral specialist
It feeds primarily on soft corals, often living right on its food source for both nutrition and camouflage.

Naked gills
Like all nudibranchs, it has exposed gills—“nudibranch” literally means naked gills.

Marioniopsis viridescens

A master of camouflage from the Indo-Pacific reefs, this rare dendronotid nudibranch blends seamlessly into its surroundings — looking more like algae or soft coral than a sea slug.

With its intricate branching gills and muted green tones, it’s easy to overlook… but for those who spot it, it’s an absolute gem of the macro world.

Tiny, delicate, and beautifully complex — another reminder that the ocean hides its best treasures in plain sight.

Interesting facts

* A true nudibranch: Marioniopsis viridescens is a dendronotid nudibranch — a type of sea slug with exposed “naked gills,” which is exactly what the name nudibranch means.
* East African roots: This species was first recorded off the coast of Kenya in shallow waters (~9 m), placing it firmly in the Western Indian Ocean region.
* Soft coral specialist: Like many dendronotid nudibranchs, species in this group are often closely associated with (and feed on) soft corals, sometimes living directly on their prey.
* Built for disguise: Its branched gills and body shape mimic coral polyps, helping it avoid predators and ambush food.
* Hermaphrodites: Like most nudibranchs, they have both male and female reproductive organs, increasing their chances of successful reproduction when they meet another individual.

Some more of the Ghost Nudi – Melibe colemani

Looking more like floating debris than a living creature, this surreal nudibranch is one of the ocean’s strangest illusions… and one of the most sought-after macro subjects underwater.

Nicknamed the “ghost nudibranch”, its almost fully transparent body reveals a web of internal organs—giving it that wild “stringy” or “floating net” look.

Meet Phyllodesmium tuberculatum — the master of disguise of the nudibranch world.

At first glance, it looks like just another piece of soft coral… but look closer. This incredible sea slug has evolved to perfectly mimic the very corals it feeds on, blending in so well that even experienced divers can miss it.

Fun facts:
• This species was first described from the Philippines, hiding among reef structures where it feeds on soft corals
• Like many in its genus, it likely steals tiny photosynthetic organisms (zooxanthellae) from its prey — meaning it can get energy from sunlight (basically a “solar-powered” slug!)
• Instead of stinging defenses, it relies on camouflage and deception — looking almost identical to the coral it lives on
• If threatened, it can drop its cerata (those finger-like appendages), which continue wriggling to distract predators

The Ghost of the Reef!

Meet the elusive Ghost Melibe, often called the “holy grail” of nudibranch sightings by underwater photographers. And it’s easy to see why…

Unlike typical nudis, this surreal creature doesn’t rely on bright warning colors. Instead, it’s almost completely transparent, blending seamlessly into its surroundings like a drifting ghost.

Fun facts:
• It feeds using a large, expandable oral hood, like a net, to scoop up tiny prey
• Its body is so translucent you can often see its internal organs
• It lacks the typical rhinophores seen in many nudibranchs
• Sightings are rare, making every encounter feel like finding underwater treasure

For many divers, spotting one isn’t just a dive highlight… it’s a once-in-a-lifetime moment.

Have you ever seen one of these ghosts in the wild?

Melibe digitata – the alien of the reef!

A favourite among underwater macro photographers, Melibe digitata stands out with its brown to greenish-brown tones and beautifully branching cerata. Its translucent body gives you a rare peek inside, revealing the digestive glands in action.

But the real showstopper? Those finely branched papillae on its cerata, perfectly mimicking green algae - nature’s camouflage at its best.

Cool facts:
✨ Unlike most nudibranchs, Melibe digitata doesn’t rely on stinging cells for defence—it relies on disguise and stealth
✨ It uses a unique “oral hood” (like a net!) to scoop up tiny prey from the water
✨ That algae-like look isn’t just pretty—it helps it blend seamlessly into its environment and avoid predators

A true master of illusion and one of the ocean’s most fascinating drifters

Meet Braun’s pughead pipefish (Bulbonaricus brauni) — one of the ocean’s tiniest and most fascinating reef dwellers.

This little guy only grows to about 5.5 cm, but it’s packed with personality. Found in warm waters from Indonesia to Western Australia and even around Japan, it sticks close to shallow coral reefs (just 1–10 m deep).

What makes it special?
🔹 Coral companion – It lives in close association with Galaxea coral, using it for protection and blending in almost perfectly.
🔹 Master of camouflage – Its odd “pug-like” head and body shape help it disappear into the reef.
🔹 Dads do the heavy lifting – Like other pipefish and seahorses, the male carries the eggs in a brood pouch until they hatch
🔹 Born ready – The babies emerge as miniature versions of adults, ready to take on reef life immediately.

Tiny hitchhiker, big adventure!

Riding in style! The emperor shrimp catches a lift on its sea cucumber host, cruising the ocean floor like royalty.

These little shrimp don’t just travel for fun — they stay close for protection and an easy meal, picking up scraps along the way. Nature’s version of “ride-sharing” at its finest.

🔍 Did you know?
• Emperor shrimp can change colour to match their host — from black to white, orange, or even translucent for camouflage
• They don’t just ride sea cucumbers — they’ll also hitch a lift on starfish, nudibranchs, and sea urchins
• This relationship is called commensalism — the shrimp benefits, while the host is mostly unaffected
• They spend most of their lives on a single host, rarely venturing off
• Despite their tiny size (often under 2 cm), they’re a favourite among macro photographers

The tiger butterfly seaslug, probably one of the coolest things I have seen in my life. Check out the video - how’s that for a groove…

This tiger butterfly seaslug may be small (only about 1–3 cm), but it’s a true underwater showstopper. Its leaf-like cerata look like a flowing gown, patterned with bold black, white, and golden tones, nature’s own high fashion.

Found in tropical Indo-Pacific waters, this little beauty can even drop parts of its body to distract predators - talk about dramatic exits