This is official site of Black Water Dive® produced by photographer Ryo Minemizu. Black Water Dive® is a kind of night diving. We are setting up underwater lights of high-color rendering on the sea bottom of night that while considering tides, times, places. The creature which appears is mainly juveniles and larvae. All is fascinating, and it's not to be seen at daytime or regular night diving. It will be your first experience. This site will introduce the state of the event and the creatures seen and also future of BWD schedules. *"BWD"stands for Black Water Dive®.*Black Water Dive® is a registered trademark of Ryo Minemizu.
ラベル ムラサキダコのオス の投稿を表示しています。 すべての投稿を表示
ラベル ムラサキダコのオス の投稿を表示しています。 すべての投稿を表示


Tremoctopus gracilis (Eydoux & Souleyet, 1852) has tentacles of jellyfish to arms.

This time, I could shooting valuable male ecology of Tremoctopus gracilis (Eydoux & Souleyet, 1852) at Palau. That is probably of a third case in the world.

Tremoctopus gracilis is a very unique an octopus of open ocean-swimming with web on the arm. The male is very small compared to the female, So far, It's have been most captured in such investigation by the plankton net.

The first discovery is by David Paul of Melbourne University. It was the world's first ecological photographed at Great Barrier Reef, in Australia. after that, first report is by Dr Norman in 2002.
At that time, it has been reported to have the tentacles of cnidarians such as jellyfish. Then, that this species is holding tentacles at selectively Portuguese Man O' War (Physalia physalis) has also been re-reported at Tree of Life Web Project. So far, how to use of this jellyfish tentacles, it has been considered for the defense or attack.

Blanket Octopus - Black Water Dive®
Tremoctopus gracilis (Eydoux & Souleyet, 1852) ,male, ML:15mm
Blanket Octopus - Black Water Dive®
seems to be tentacles of Physalia physalis on the sucker arm.

Related report

Larva of Blanket Octopus


Sweeney, M.J., Roper, C.F.E., Mangold, K.M., Clarke, M.R., and Boletzky, S. v. 1992. 'Larval' and juvenile cephalopods: a manual for their identification. Smithsonian Contributions to Zoology - No. 513. 282pp.

Norman, M.D. 2000. Cephalopods A World Guide. Frankfurt, Germany, IKAN Publishing. 320 pp.

Jereb,P., Roper,C.F.E.,Norman,M.D.,Julian,K.F., 2014. Cephalopods of the World. An annotated and illustrated catalogue of Cephalopod species known to date Volume 3 Octopods and Vampire Squids. FAO Species Catalogue for Fishery Purposes No.4, Vol.3. 382pp.