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.

2017年1月27日金曜日

2017年1月23日月曜日

2017年の沖縄本島でのブラックウォーターダイブ®第1弾・第2弾

2017年の沖縄本島でのBlack Water Dive®第1弾・第2弾は、下記の日程に決まりました。皆様のご参加をお待ちしております。

沖縄本島 Dolphinkick

  • 3/31(金)-4/3(月)
  • 6/14(水)-6/17(土)
開催店:Dolphinkick(ドルフィンキック)
HP:www.dolphinkick.jp
参加のお申し込み&お問い合わせ:TEL: 098-963-6640(Dolphinkick)


詳細はご案内PDF

2017年1月12日木曜日

Record of Cardiapoda richardi from Kume Island


Cardiapoda known only two species from worldwide.
  • Cardiapoda richardi Vayssiere, 1903
  • Cardiapoda placenta  (Lesson, 1830)

Cardiapoda richardi

C. richardi is smaller species than C. placenta.; the tail is long like a filamentous; gill handle is shorter than C. placenta. ; gill number is eight; shell is not characterized at old literature but, actually they has a very thin shell. Retractable brown, membranous structure on the mid ventral surface of the tail. Lens of eye rests in a surrounded in a U-shaped retina. Japanese name is "Muchio-Zoukurage". "Muchio" mean tail shapes filamentous. "Zou" mean an elephant. "Kurage" mean a jellyfish.

About this individual

These pictures all took at Kume-Island Okinawa Japan. Size: about 35mm. This individual is female. Because egg strings is releasing from near the gill and Cardiapoda is known that fin sucker present only in males. Body is covered with many reddish pigment. There was a behavior to round the body. This is considered to be for defense. Brown membrane appeared only at that time. In normal posture the brown membrane is stored in the ventral surface of tail.

Cardiapoda richardi ムチオゾウクラゲ
Egg strings is releasing from near the gill

Cardiapoda richardi ムチオゾウクラゲ
Gill number is eight they has a very thin shell

Cardiapoda richardi ムチオゾウクラゲ
Lens of eye rests in a surrounded in a U-shaped retina.

Cardiapoda richardi ムチオゾウクラゲ
Retractable brown, membranous structure on the mid ventral surface of the tail.

Cardiapoda richardi ムチオゾウクラゲ
normal posture, brown membrane is stored in the ventral surface of tail.

<<References>>

Cardiapoda richardi - Tree of Life Web Project 

Chihara, M. & Murano, M. eds. ,1997 An Illustrated Guide to Marine Plankton in Japan.  Description: xxxvi, 1574pp, Tokai University Press, Tokyo Japan. (in Japanese)

Ryo Minemizu et al ,2015 A Photographic Guide to the Jellyfishes of Japan. 360pp. Heibonsha, Tokyo Japan. (in Japanese)

2016年11月18日金曜日

Phylliroe bucephala is eating Rhizophysa eysenhardtii or R. filiformis

Phylliroe bucephala is eating Rhizophysa eysenhardtii Peron & Lesueur, 1807 or R. filiformis (Forskål, 1775)
P. bucephala is not so rare planktonic nudibranch. It's found at tropical and subtropical sea throughout the world. Especially, It's found many at the current-rip.

The body is thin and flat. The shape looks like a flounder fish. It has ability to bioluminescence.

Rhizophysa is kind of Siphonophorae jellyfish. They are known stocking strong poison to cnidocyte.

Phylliroe bucephala is eating Bathyphysa conifera or R. filiformis
Phylliroe bucephala is eating Bathyphysa conifera or R. filiformis


Location: Kume-Island Okinawa Japan
Time & Date: 20:30, 05, Nov, 2016
Depth: 5m, Sea Temp: 25℃
Specimen Size: 40mm


*Phylliroe bucephala Lamarck, 1816
=Phylliroe bucephalum Peron & Lesueur, 1810

Japanese name"konoha-umiushi"
="konoha" mean leaf.
="umiushi" mean nudibranchs.


<<References>>

WoRMS - World Register of Marine Species - Phylliroe bucephala Lamarck, 1816

The Sea Slug Forum - Phylliroe bucephalum

2016年9月29日木曜日

Larva of Malacanthus brevirostris Guichenot, 1848

This larva is Malacanthus brevirostris Guichenot, 1848. Taken at Black Water Dive® in Kume island Okinawa Japan.
Total length is about 55mm, relatively large larva. Snout is short protrusion. Frequently to treading water. 

Color: Red horizontal stripes pattern on body. Caudal fin has yellow-green dye, the edge has been framed in white and that outside is transparent. The rim and the base of the dorsal and ventral fins has red and yellow-green spots.

Larva of Malacanthus brevirostris Guichenot, 1848  TL:55mm

REFERENCES:
Nakabo, T. (ed.), 2013. Fishes of Japan with pictorial keys to the species, third edition. Tokai University Press, Kanagawa, Pp, 2428. (3-Volume Set)  (in Japanese).

Okiyama M. (ed), 2014. An Atlas of Early Stage Fishes in Japan Second Edition Tokai University Press, Japan. :Pp,1912. (in Japanese).