Cuthona ornata
Baba, 1937
Order: NUDIBRANCHIA
Suborder: AEOLIDINA
Family: Tergipedidae
DISTRIBUTION
Known from Japan & Hong Kong
PHOTO
Tiu Chung Chau, Hong Kong, 30 March 1985, 5m, AM C146966. Photo: Pres B.W.Darvell.
Background colour of the body translucent orange. The oral tentacles and smooth tapering rhinophores are translucent watery orange at the base, changing to a translucent yellow about halfway up. There can sometimes be a pair of bluish white lines of the head running from in front of the rhinophores to along the basal half of the oral tentacles. The most distinctive colour feature of this species is the bright blue digestive gland which colours the cerata except for an apical bright yellow cap. In some cases the upper part of the digestive gland can be a blackish colour so that cerata looks as though it is bright blue with a black band then a yellow cap. It can grow to 15mm long.
Reference:
• Baba, K. (1937) Opisthobranchia of Japan (II). J. Dept. Agric. Kyusyu Imp. Univ. 5(7): 289-344. (Pls.1-2)
• Baba, K. (1955) Opisthobranchia of Sagami Bay, Supplement. Iwanami Shoten, Tokyo. 59pp., 20 Plates
Rudman, W.B., 2001 (August 9) Cuthona ornata Baba, 1937. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/cuthorna
Related messages
Cuthona ornata from eastern Russia
May 16, 2005
From: Alexei Chernyshev & A. Ratnikov
Dear Bill,
Cuthona ornata is a rare species in Peter the Great Bay (Martynov, 2002). Here it was found only in warm season (August and September).
Locality: Peter the Great Bay, Russia, Sea of Japan, Pacific Ocean. Depth: 2 m. Length: 10 mm. August 2002. on Codium sp. Photographer: A. Ratnikov.
-
Martynov A. V. (2002) The new species of the genus Trinchesia Ihering, 1879 from Peter the Great Bay, Japan Sea (Nudibranchia, Tergipetidae), with notes on the taxonomy of the family. Ruthenica, 12(1): 45-54 (in Russian).
Best regards,
Alexei & Alexander
tsher@bio.dvgu.ru
Chernyshev, AV., & Ratnikov, AV. , 2005 (May 16) Cuthona ornata from eastern Russia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13767Dear Alexei & Alexander,
Thanks for another report from the Russian far east. It is very interesting to see photos of these animals and compare them with the fauna of Japan and the rest of the northern Pacific.
Best wishes,
Bill Rudman
Nudibranch will travel by decorator crab
May 11, 2005
From: Dong Bum Koh
Dear Bill
Concerning the message #13718.
The photo is a evidence of Nudibranch will travel by decorator crab.
You can find a small nudibranch on the hydroids attached to this camouflaged decorator crab, Pugettia quadridens .
Locality: Aewol, South Korea. Depth: 11 m. Length: Several mm. Sep. 1994. Rocky bottom. Photographer: Dong Bum Koh
Best regards,
Dong Bum Koh
drkoh@seasee.co.kr
D. B. Koh, 2005 (May 11) Nudibranch will travel by decorator crab. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13741
Dear Koh,
This is an interesting photo. It looks like the crab has cut off branches of the hydroid colony and attached them on its carapace. As you can see in the close-up photo there is indeed at least one nudibranch along for the ride. I am pretty sure it is Cuthona ornata.
Best wishes,
Bill Rudman
Cuthona ornata from Japan
November 14, 2003
From: Yukari Sato
Hello Dr.Rudman,
I have found this animal at Zushi, Japan.
I think this is Cuthona ornata. I am happy if you have any comment.
Upper Photo:
Date: 4 May 2003
Depth: 15m
Size: approx.15-20mm.
Location: Zushi(near Hayama), Sagami Bay, Japan
Lower Photo:
Date: 3 Aug 2003
Depth: 22m
Size: approx.8mm.
Location: Zushi(near Hayama), Sagami Bay, Japan
A small animal, 5mm long alive, was seen at the same locality on 8 June 2003. Depth: 15m
Best regards,
Yukari Sato
yuks@cg7.so-net.ne.jp
Dear Yukari,
Yes I agree that this is Cuthona ornata. It is good to see some photos showing the extent of the colour variation in the species
Best wishes
Bill Rudman
Cuthona ornata from Japan
May 23, 2002
From: Nishina Masayoshi
Dear Bill,
My wife has taken some good photos of Cuthona ornata.
Date: 4 May, 2002
Loc: Echizen coast, Fukui Pref. Japan
Length: 8mm
Depth: 7m
found and photographed by N. Chikako
Best Regards,
Nishina Masayoshi
nishina@wips.co.jp
Masayoshi, N., 2002 (May 23) Cuthona ornata from Japan. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/6964Dear Nishina & Chikako,
Thanks for these excellent photos of Cuthona ornata. It is good to get some photos from Japan to match those we have from Hong Kong.
Best wishes,
Bill Rudman
Cuthona ornata from Hong Kong
August 14, 2001
From: Bernard Picton
Hi Bill,
Here is a scan of Cuthona ornata from Hong Kong. We collected this species twice during the workshop, I expect Brian Darvell got more after that? I see you don't have it on the Forum yet, Bob Bolland has it at his site, but the main picture looks like a different species to me, whilst his secondary page looks exactly like the Hong Kong specimens.
11 Apr 1983 - NW Kong Chau, Mirs Bay - BEPHK101 - 5-10m
Bernard
bernard.picton.um@nics.gov.uk
Picton, B.E., 2001 (Aug 14) Cuthona ornata from Hong Kong. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/5056Dear Bernard,
I'll sort out and add Brian Darvell's other records. As you will have noted I am gradually adding his Hong Kong records.
Looks like the yellow on the cerata can be missing at times and the oral tentacles and rhinophores can be pale blue, as in your photo and Bob Bolland's second image. However I don't think Bob's first image is C. ornata.
Best wishes,
Bill Rudman
