Sunday, January 29, 2006

Banded Pipefish


Banded Pipefish. Try saying this scientific name three times ...
Dunckerocampus dactyliophorus.

Janolus


This is an unnamed species of Janolus photographed at Pertamina Pier in about 6M. This animal is on the cover of Takamasa Tonozuka's book on Opistobranchs of Bali and Indonesia. The book is written mostly in Japanese but the photos are excellent and identified by their scientific names.

Saturday, January 28, 2006

Monday, January 23, 2006

Whale Shark Shrinking

This article explains why we haven't seen many whale sharks here in Timor, they're just too damn small!

Researchers: Whale Shark Shrinking
January 19, 2006 12:30 p.m. EST
Hector Duarte Jr. - All Headline News Staff Reporter


London, England (AHN) – Researchers say whale sharks off the coast of Australia are getting smaller. In one decade, the average size recorded by observers has shrunk from 7 to 5 meters.

Whale sharks, the world’s largest fish, are caught for food in some East Asian countries and Australian researchers fear this could be the cause of the decline. The fish is listed as being vulnerable and one of the authors of the study says the new finding is much cause for concern.

These findings were provided by ecotourism companies that run tours to watch and swim with whale sharks at Ningaloo Marine Park, off the northwest Aussie coast.

Says Mark Meekan of the Australian Institute of Marine Science (Aims), "We have obtained those datasets and analysed them over time and essentially what we have seen in the last decade is a decline in average size of shark from 7m to 5m. Now, if you consider that the sharks probably aren't sexually reproductive or mature until they're 6 or 7m long - that's a very worrying sign."

Sunday, January 22, 2006

Sunday at Bob's Rock

Dive conditions were less than ideal today at Bob's Rock, only 5 meters of visibility and chilly water (25C). Here are three shots from the dive.

Giant Moray with Cleaner Shrimp


Banded boxer shrimp, Stenopus hispidus, cleaning a Giant Moray, Gymnothorax javanicus. The moray was hanging out under the barrel sponge on the east side of Bob's Rock.

False Cowery?


Perhaps a False Cowery (6mm).

Ceratosoma trilobatum


Ceratosoma trilobatum (10cm)

Friday, January 20, 2006

The Answer

Tuesday's question was correctly answered by two overachievers, Nick Hobgood (who answered in about 16 seconds after the photo was posted) and Dave McKee (all the way from Jerusalem). The photo is of eggs inside the fused pelvic fins of a Robust Ghost Pipefish, Solenostomus cyanopterus.

Ghost pipefishes comprise a small family (Solenostomidae) of skin-brooding fishes related to true pipefishes and seahorses (Syngnathidae). Solenostomus embryos develop within the fused pelvic fins of the female, unlike syngnathids in which males brood the eggs. Embryos, enclosed in egg envelopes, are attached to epidermal stalks, termed cotylephores, that occur only in brooding females.

For more details about pipefish reproduction, check out "Adaptations for reproduction and development in the skin-brooding ghost pipefishes, Solenostomus"

Coincidentally, I had posted another photo of a Robust Ghost Pipefish just a few days earlier.

Tuesday, January 17, 2006

Anybody care to guess?


Lendell and I found this tonight as Sandy Bottom. Anybody care to guess before I disclose the details?

Sunday, January 15, 2006

Crinoid squat lobster


Allogalathea elegans. Usually crinoid squat lobsters are the same color as their host crinoids and are masters of camouflage. This black and white individual, however, was quite easy to find in the yellow-orange feather star.

Friday, January 13, 2006

Aglajid eating a benthic ctenophore



In December I posted a series of shots entitled "Carnivorous Nudibranch", depicting what I thought was a nudibranch eating some kind of gastropod. Leslie Harris, Collection Manager of Allan Hancock Foundation Polychaete Collection at the Natural History Museum of Los Angeles County, saw the posting and suggested that I write to Dr. Bill Rudman, Principal Research Scientist in the malacology department at the Australian Museum, Sydney.

Here's a letter I submitted yesterday to Dr. Rudman at the Sea Slug Forum.







Aglajid eating a benthic ctenophore
January 13, 2006
From: Brian Francisco

Hi Bill

Leslie Harris suggested that I send you the attached photographs. They depict an opistobranch (Leslie believes either in the family Aglajidae or Gastropteridae) eating a benthic ctenophore, genus Coeloplana. The photographs were taken on a sandy slope at 12M about 25 km west of the capital in East Timor.

Although the ctenophore was nearly the same size as the opistobranch (3-4 cm), the latter had no trouble engulfing the former. The event happened rather quickly, with no hesitation whatsoever, perhaps 8-10 seconds. In the third photo, a branched feeding tentacle can be seen coming off the right side of the ctenophore, even while most of it's body is inside the opistobranch.

The opistobranch then quickly buried itself.
Brian Francisco

uwet.blogspot@gmail.com

Francisco, B., 2006 (Jan 13) Aglajid eating a benthic ctenophore. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find.cfm?id=15543


This is Dr. Rudman's response.



Dear Brian,

I am glad Leslie encouraged you to send this message. This is a whole series of 'firsts'. I suspect it is the first record of a benthic ctenophore being eaten by an opisthobranch, and the opisthobranch is almost certainly an aglajid, but I am pretty sure it's an unknown species. From the general shape, it is possibly a species of Philinopsis but the slender pointed tip to the posterior edge of the head shield is rather unusual. It reminds me a lot of the animal I have on the Forum as Aglajid sp 9. I wonder if the similarity in colour between the aglajid and the ctenophore is mere coincidence?

We don't know much about the biology of benthic ctenophores, in fact when I do a web search I usually end up on the Sea Slug Forum, where we have photos of a number of species, and some spectacular shots of animals with their feeding tentacles greatly expanded. Aglajids are unusual opisthobranchs because most have lost their radular teeth and so have evolved ways of feeding which involve either sucking in their prey whole - like eating a piece of spaghetti - in the case of the worm-eating Melanochlamys, or engulfing it by everting a large cylindrical buccal bulb - in the case of Philinopsis - which feeds on cephalaspidean bubble shells. Your animal has a foregut then, which is quite capable of engulfing a large prey item such as a benthic ctenophore.

To my knowledge no aglajid has been reported to feed on such prey before. You have made a very interesting discovery.

Best wishes,
Bill Rudman

Rudman, W.B., 2006 (Jan 13). Comment on Aglajid eating a benthic ctenophore by Brian Francisco. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find.cfm?id=15543

Wednesday, January 11, 2006

Tuesday, January 10, 2006

Sea Horse Hunting

Thanks to dive buddies Nick, Greg, Shane and Daphne for a fantastic dive in the cove behind Cristo Rei. Although we didn't find any sea horses, we found lots of other cool stuff.

Philinopsis pilsbry


Greg found this fantastic opistobranch, Philinopsis pilsbry, 3.5cm

According to Debilius, the Philinopsis pilsbry is "a rare species often only encounted as individuals" Known in Thailand, Indonesia, and Australia.

Unidentified Dragonet found at 1M.

Maritigrella eschara


Beautiful Flatworm Maritigrella eschara

The measurement

And finally...

Sunday, January 08, 2006

Sunday Bubble Beach


Strange object in this fish's right gill area, perhaps a parasitic copepod, whatever that is.

Flabellina bilas


Flabellina bilas is the only species of nudibranch with red bands on the cerata and rhinophores.

Pliopontonia furtiva


Pliopontonia furtiva. (6mm) There were two individuals on this disc anemone, the larger one was buried inside the folded lip of the anemone .

Friday, January 06, 2006

Spawning Anemone


While diving at Sandy Bottom last night, I came upon a spawning carpet anemone which I believe to be a Hadden's Sea Anemone (Stichodactyla haddoni). The Hadden's is a large anemone (this one only about 50cm), usually found on sandy slopes, with folds at its edge and short, tightly-packed tentacles. Tentacle color is usually green or brown, but sometimes variegated. It has a whitish column with "non-adhesive verrucae" (look that up) in the same color or pinkish.

Hadden's sea anemones have an obligate symbiosis with anemone fish, in this case, Amphiprion clarkia, distinguishing it as a "host anemone". Of the more than 1,000 species of sea anemones found throughout the world's oceans, only ten of these species are "hosts" to clownfish.

Now for the good part...While it's difficult to find information specific to the spawning process of Hadden's Sea Anemones, there are current sources such as The University of Kansas, Biodiversity Research Center which discuss anemone reproduction. According to the BRC, anemones "reproduce sexually. An individual of some species may produce both eggs and sperm; host anemones appear to have separate sexes" [emphasis mine]. This is assertion that host anemones are either male or female is supported by the work of Anna Scott, from the Southern Cross University in northern New South Wales. Scott filmed anemones spawning (apparently for the first time in 2003) and noted that the release of eggs from the female are likely triggered by the release of sperm from the male anemone. Fertilization, she said, only takes place once the eggs and sperm connect in the water column.

From my observations last night, this information seems to be correct; I was likely observing a female releasing her eggs into the water. When the female released her eggs, the Clark's anemone fish went straight for the anemone's 'mouth' and ingested as many eggs as possible. This lasted for only 30-45 seconds until the release of eggs decreased. Upon review of the photos from the dive, there appears to be a cloud, perhaps of sperm, surrounding the anemone fish. I have come up with two possibilities: One is that the cloud is, in fact, sperm and that the Hadden's anemones are capable of asexual reproduction, producing both eggs and sperm, like some other "non-host" anemones. Or two, that the cloud is simply the waste product of the anemone fish as it feasted on the released eggs. My guess is the latter, but if you have any other theories or additional sources of anemone spawning information, please let me know...email me.

Wednesday, January 04, 2006


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Com and Tutuala

Just a few more photos from this weekend's trip to Com and Tutuala.

All of the underwater shots from Com and Tutuala were taken with a Sony P150 in a Sony housing with a Sea & Sea YS 25 Strobe.

Spotted Moray


Notice the smaller shrimp on the eel's jaw, but you may have to click on it to see the larger photo.

Hunting Cuttlefish


This cuttlefish was digging around in coral rubble and came out with a crab.

Close-up

Demon Stinger