Little Fish with the Hollywood Lips

Big-lip Damsel, Cheiloprion labiatusNovember 2015, Lembeh Strait, Indonesia ~ Cheiloprion labiatus, the Big-lip Damsel, fascinates me. How have we managed to dive throughout its range for so long without ever noticing it? Last month, our friend Janet Eyre noted several during a REEF fish survey in Lembeh Strait and pointed them out. Damselfishes are ubiquitous on the reefs we visit but the ones that usually catch my eye are brightly colored juveniles. By the time the Big-lip Damsel develops its Hollywood lips, it is drab brown; definitely not flashy.

Why a fish would evolve with such an odd-looking feature made sense when we learned what it eats. While some damsels pick plankton and others feed on algae and/or benthic invertebrates, the Big-lip Damsel feeds on the tentacles of the polyps of Acropora corals. Each tiny, fleshy tentacle of this stony coral is surrounded by the sharp, skeletal part of the corallite – no problem for the Big-lip Damsel.

Big-lip Damsel in coral thicket

Video frame capture: Big-lip Damsel tucked into its Acropora thicket

Ensconced in the Acropora thickets it feeds upon, it really has no reason to leave the protection of the coral, making it easy to miss but once we had a search image for the fish, we were able to takes others back to see them. The Big-lip Damsel has a big range: from Sri Lanka to Vanuatu and from the Philippines down to Australia, so we’ve had plenty of chances to see it but it was just “off our radar” – no telling what other fascinating animals we’re overlooking. Here’s some video:

A Shark Egg Case!

Shark Egg Case in the Philippines

Video frame capture: Shark Egg Case – Maybe a Bamboo Shark?

This is a frame capture from a video I shot earlier this year in Anilao, Philippines. I have found empty egg cases washed up on the beach (beachcombers call them mermaid’s purses), but never one with its little living treasure: a yolk and developing shark embryo. I have no idea what species this is – maybe a bamboo shark, one of several small species of oviparous (egg-laying), bottom dwelling sharks found throughout the Indo-Pacific. I’m familiar with the Brownbanded Bamboo Shark (Chiloscyllium punctatum) and the Whitespotted Bamboo Shark (Chiloscyllium plagiosum); both species are found in the Philippines.

At the beginning of our dive, I was distracted by spawning coral (unusual for the middle of the day) and got separated from Ned and our group. I surfaced and told the boat crew I would stay under the anchored boat, at 15 feet depth, and re-board when I heard them start the engine to pick the others up. The boat was anchored away from the reef, in a spot that was mainly rubble; what we call “alternate habitat”. There are advantages to slowly examining one small area, so I was content to spend my hour in the shallows directly under the boat.

The egg case was firmly attached to the top of a small rubbly coral mound but didn’t look like the shiny, clean cases I’ve found on the beach and seen in aquarium exhibit photographs. It was covered in a thin coat of algae but I could clearly see something bright orange undulating inside. When I gently rubbed a little of the algae off, the embryo stopped moving and I realized I was looking at a developing shark! To my relief, it wasn’t long before it started the undulating motion again.

Back on shore, a quick Internet search turned up quite a few images of shark egg cases and an interesting paper, “Survival of the Stillest: Predator Avoidance in Shark Embryos”. The embryo’s undulating motion aids in moving fresh seawater in and out of the egg case, which aids in respiration. Using Bamboo Shark eggs, the researchers found that the embryonic sharks react to possible predators with a freeze response, possibly to avoid alerting the predator by scent or water movement. If the little embryo froze because it perceived I was a predator, I’m glad it resumed its normal behavior so quickly.

It was difficult to shoot video because there was no place to set my camera down to steady it – but here’s a short bit:

Lembeh 2015 Portfolio – Part 2

Mandarinfish trio in Lembeh Strait, Indonesia

A seemingly congenial afternoon gathering of male Mandarinfish precedes their nightly ritual of highly competitive courtship confrontations.

Lembeh Strait Part Two, November 2015 ~ Here is the second installment of favorite photos from our two-week stay at Eco Divers Resort Lembeh. Friends who visited Lembeh earlier reported unseasonably cold water and strong winds so we were bracing for the worst but as luck would have it, the wind died and water warmed just before we arrived at the end of October.  We have dived here in every month of the year but this month the bottom seemed more interesting than usual – maybe it was the cooler summer. Just coming off the publication of the second edition of Reef Fish Identification: Tropical Pacific, Ned was tuned into fishes but there seemed to be more octopuses and nudibranchs too. We left in the best way to leave a place: wishing we had one more day to go back and see that jawfish/blenny/flasher wrasse just one more time.

A thumb-sized Poisonous Ocellate Octopus, Amphioctopus siamensis, on high alert as an Algae Octopus approaches:

Poisonous Ocellate Octopus on high alert

 

The Algae Octopus, Abdopus aculeatus, dancing across the bottom:

Algae Octopus, abdopus aculeatus

 

The Ocellate Octopus flees…

Poisonous Ocellate Octopus flees from another octopus

 

… to safer terrain:

Poisonous Ocellate Octopus lands after fleeing from another octopus

 

A scientifically undescribed one-inch jawfish leaps from its sand burrow. Although we could see these tiny jawfish jumping all around him, Ned had decided, after watching them on an earlier dive, that he had to just select one individual and work it. He spent an hour with this little fish:

Undescribed jawfish in Lembeh Strait

 

A scientifically undescribed Flabellina nudibranch:

A scientifically undescribed Flabellina nudibranch

 

A scientifically undescribed Godiva nudibranch:

A scientifically undescribed Godiva nudibranch

 

Funeral Jorunna, Jorunna funebris, nudibranch:

Funeral Jorunna, Jorunna funebris

 

Instead of the traditional topknot of sponge, this Redspot Sponge Crab, Lewindromia unidentata, was carrying a clipped piece of soft coral:

Redspot Sponge Crab, Lewindromia unidentata

 

At the base of a soft coral, a squat lobster:

Squat lobster

 

A decorator crab adorned with hydroid polyps:

Fairy decorator crab

 

A Whitebelly Toby inflates with water to thwart being swallowed by a lizardfish:

Lizardfish trying to eat a toby

 

Over the years of watching the behavior of squid and cuttlefishes, we’ve never actually made physical contact with one. After being followed almost the entire dive by an overly friendly Broadclub Cuttlefish, Anna extended her hand and much to our surprise, it eased forward and stroked her hand:

A cuttlefish touching diver's hand

 

A False Cleanerfish, Aspidontus taeniatus, exposes its fangs in an effort to deter predators from its egg nest:

False Cleanerfish, Aspidontus taeniatus

 

A sesame seed-sized mysid (Crustacea: Mysida):

Mysid (Crustacea: Mysida)

We’ll be back soon with more favorites from our travel this year. Be sure to “like” our Blennywatcher Facebook page and check out our Blennywatcher YouTube Channel.

Lembeh 2015 Portfolio – Part 1

Coconut octopus, Amphioctopus marginatus

Coconut Octopus— a Lembeh classic—curls inside a large bivalve shell.

Lembeh Strait—Once Again! Part One, October 2015 ~ The narrow 12-mile stretch of water separating Lembeh Island from the large island of Sulawesi in Indonesia is home to one of the Earth’s most diverse displays of natural selection and symbiosis above or below water. Even after [...]