Deception and Disguise: A Closer Look at Mimicry in Lembeh
When it comes to marine biology, looks can be deceiving. In the rich, biodiverse waters of North Sulawesi, many marine creatures rely not on speed or strength, but on deception for survival. The evolutionary trait of mimicry – where one species evolves to resemble another, or blends seamlessly with its environment – is one of the most fascinating strategies in the underwater world. And Lembeh Strait is one of the best places on Earth to witness it in action.
In this article, we explore the fascinating world of mimicry in Lembeh, to reveal how it works, which species are taking it to the next level, and how you can see it in action. Let’s dive in.
What Is Mimicry?
Mimicry is a form of camouflage found throughout the animal kingdom. In marine environments, it allows species to hide from predators, sneak up on their prey, or even fool potential mates. Broadly speaking, mimicry can be:
- Protective (to avoid being eaten),
- Aggressive (to help ambush prey), or
- Reproductive (to aid in mating behavior)
Some species even engage in something called ‘Batesian’ mimicry, whereby a harmless animal imitates the warning signals of a dangerous one – an evolutionary bluff that often pays off.
In the Lembeh Strait, this evolutionary arms race is on full display. From seahorses and shrimp to frogfish and nudibranchs, mimicry is everywhere – if you know where to look.
The Art of Staying Hidden: Protective Mimicry
One of the most iconic examples of protective mimicry in Lembeh is the pygmy seahorse.
The Bargibant’s pygmy seahorse (Hippocampus bargibanti) lives exclusively on Muricella gorgonian corals, matching the polyp structure and color so perfectly that even seasoned divers sometimes struggle to spot them. Our experienced dive guides at Lembeh Resort are skilled in spotting these masters of disguise in their natural habitat.
Another seahorse species in Lembeh, the Pontohi pygmy seahorse (Hippocampus pontohi), can be found on algae-covered rubble and hydroids, where its white-and-gold coloration mimics a blade of algae or coral debris. Despite their tiny size, these miniature masters of disguise have evolved astonishing detail in their mimicry, allowing them to go unnoticed by predators.
Other examples of protective mimicry in Lembeh include cryptic shrimp (Gelastocaris paronae) that blend into sponge surfaces, and Tozeuma shrimp (Tozeuma lanceolatum); a group of long-bodied, color-variable crustaceans that hide on everything from black coral bushes to algae tufts. Their camouflage goes beyond coloration, to include posture and behavior – by staying perfectly motionless, these critters can blend seamlessly into their background.
Aggressive Mimicry: Lurking in Plain Sight
Not all mimicry is about hiding. Some species use it as a weapon. Members of the Frogfish (Antennariidae) family, for example, are ambush predators that use aggressive mimicry to devastating effect.
The painted frogfish (Antennarius pictus) mimics sponges down to the smallest detail, even sporting spots that resemble sponge pores. Sargassum frogfish (Histrio histrio), on the other hand, drift in floating algae mats near the surface, blending perfectly with the tangled vegetation.
But it’s not just their appearance that tricks prey. Frogfish also have an evolutionary ace up their sleeve: a modified dorsal spine tipped with a fleshy lure (known as an esca). Different species have developed lures shaped like shrimp, worms, or small fish, and they’ll ‘fish’ with this appendage until an unlucky victim gets too close – then it’s swallowed whole in the blink of an eye.
Want to learn more about frogfish in Lembeh? Check out this blog.
Batesian Mimicry in the Lembeh Strait
In Batesian mimicry, a harmless species copies the appearance or behavior of a potentially harmful or dangerous one. A standout example in Lembeh is the black saddle filefish (Paraluteres prionurus), which closely resembles the saddled toby (Canthigaster valentini), a species of toxic pufferfish.
Both species are often seen swimming together in mixed schools. To the average predator, there’s little to distinguish between the two – so the filefish gets a free pass simply by association. It’s mimicry by proximity, and it works.
Nudibranchs That Disappear
Nudibranchs may be some of the ocean’s most colorful residents, but that doesn’t mean they always want to be seen. Species from the Phyllodesmium genus take camouflage to the next level – these soft coral-feeding nudibranchs often mimic the very corals they consume.
Phyllodesmium rudmani, for instance, is nearly indistinguishable from the pulsing tentacles of Xenia soft corals – until it moves across the substrate and reveals its true colors. Other species, like Phyllodesmium crypticum and Phyllodesmium lizardensis, are similarly well-disguised, making them a thrilling (and sometimes frustrating) assignment for macro photographers.
Even the juvenile common egg cowry (Ovula ovum) gets in on the act, mimicking Phyllidia nudibranchs, which are known to contain chemical defenses. By pretending to be something toxic, this harmless snail reduces its chances of being eaten.
There’s More to Mimicry Than Meets the Eye
One of the most intriguing aspects of mimicry is that it’s not purely visual. Many species also mimic the behavior of their muse.
For example, frogfish will stay perfectly still like sponges, waiting patiently to ambush their prey; robust ghost pipefish (Solenostomus cyanopterus) drift with the current like pieces of seagrass; and twin-spot gobies (Signigobius biocellatus) mimic crabs, with eye spots resembling crab claws and a distinctive sideways, scuttling motion across the sand.
In each case, it’s the mix of appearance and behavior that completes the illusion. For divers and underwater photographers with an eye for mimicry in Lembeh, this blend of appearance and behavior is a captivating combination.
To find out more about ghost pipefish in Lembeh, read this recent blog.
Mimicry in Lembeh: See It for Yourself
Mimicry in the Lembeh Strait is more than just a biological curiosity – it’s a constant reminder that evolution rewards creativity. In a world where being seen can mean being eaten, the best strategy is often to become something (or someone) else entirely.
In this article, we’ve covered just a handful of species that use mimicry in Lembeh – as with all things here in North Sulawesi, there’s always plenty more to explore! So, on your next dive in Lembeh, challenge yourself to spot the imposters. Look twice at every sponge, algae tuft, or soft coral. What appears ordinary might, in fact, be watching you.
Ready to meet the masters of disguise? Join us for world-class diving at Lembeh Resort, where our expert local guides will reveal some of the most bizarre and beautiful mimicry in the marine world. For more information, please get in touch.
You can also watch a short video about mimicry in Lembeh, by tuning into our Lembeh Learning Series on YouTube.
