June 22, 2013
There’s life to be found in all sorts of weird and unexpected places on the reef. This tiny and beautiful cowrie was found on the surface of a soft coral at Pulau Jong, on a dive survey conducted during the Mega Marine Survey. It would have been easily missed without careful inspection!
A Trapezia crab hides within a Acropora coral. These small commensal crustaceans live their whole life within the branches of Pocillopora corals and Acropora Corals if no Pocilloporid corals are available. In a symbiotic relationship with its host coral, the Trapezia Crab is thought to feed on particulates trapped by the coral polyps, fallen detritus, and the coral’s secreted mucus. In turn, the crabs guard the coral from invaders and fend off predators.
Wrapped around this whip coral is a tiny brittle star with a center disk as big as the surrounding coral polyps.
A Gorgonian Goby (Braninops sp.)
It was only during these survey dives that I noticed these tube worms that live burrowed within the whip corals.
During the night dive at Kusu Island, there were plenty of these little crabs in the Heliopora.
There was a gorgeous Thorny oyster. If you look closely, you can see its eyes on the fringe between the mantle and its shell! They are grouped in the same superfamily as the scallops, but like the true oysters, they cement themselves to rocks, rather than attaching themselves by a byssus. Their key characteristic is the two parts of their shells are hinged together with a ball and socket type of hinge, rather than a toothed hinge as is more common in other bivalves.
Spondylus spp. have multiple eyes around the edges of the shell, and they have relatively well-developed nervous systems. Their nervous ganglia are concentrated in the visceral region, with recognisable optic lobes connected to the eyes.
Spondylus shells are much sought after by collectors, and there is a lively commercial market in them. 
As on every night dive, there were heaps of hermit crabs. Some of them were mobile and ran around in their own shells, like the one above.
Others like the one above, remain burrowed in the coral.
Snails are interesting and they can make a surprisingly fast get away too! They manage this by simply detaching themselves from the substrate they are clinging onto, and drop themselves into a crevices of the coral that are (hopefully) difficult or impossible the predator to reach.
A beautiful Arabian cowrie Cypraea arabica
I saw a Sauron shrimp on this night dive but didn’t manage to take a photo. This one above is a kind of hingebeak I think? There’s never enough time for a night dive! There’s just so much bizarre stuff to discover!
Here are the Tweets I posted from today’s expedition:
Hope the storm last evening/night didn’t turn the waters terrible! Was really enjoying the good visibility yesterday!
Just spoke with Dr de Graves, Oxford Natural History Museum, we’ve found 14 new records for shrimp in Sg so far!
Dr Zeehan sorts the fish from the mangrove survey! Pandaka is one of the smallest vertebrate animals in the world! http://twitpic.com/cv69ou
Two new records of hermit crabs fr this mornings dive! Pseudopaquristes monoporus & Diogenes pallescens! http://twitpic.com/cv6bv9
Dive at Jong: frogfish, ovulid, Crinoid shrimp, acopora goby, diadema shrimp & I learned what an alveopora coral is! http://twitpic.com/cv64jk
Night dive at Kusu: massive lobster, crabs, aeolid nudis, stick pipefish, porcelain crabs, batfish, octopus, rabbitfish etc etc
Night survey @ Kusu: flying fish, garfish, sauron shrimp, slipper & squat lobsters. Massive lobster, squid, cuttlefish, gobidon
The Bukom oil refinery cloud – formed through the release of various gases, illuminated by its city-esque lights. http://twitpic.com/cur8bq