Thuridilla albopustulosa
Gosliner, 1995

Order: SACOGLOSSA
Superfamily: ELYSIOIDEA
Family: Elysiidae

DISTRIBUTION

Philippines, Papua New Guinea, Indonesia, Aldabra Atoll & South Africa

PHOTO

Upper: Zushi (near Hayama), Sagami Bay, Japan. 8 Jun 2003, Depth: 27m. Size: 15mm. Photo: Yukari Sato.
Lower: Malapascua Island, Philippines, 6 March 2004. Approx 20-25mm long. Depth: 4-5 metres. Photo: Paul Osmond.

The living animals are light blue with scattered translucent blackish pigment especially near the foot. There is an opaque white band along the edge of the parapodia and the parapodia are covered with scattered opaque white or cream spots or longitudinal bands. The dorsal part of the head is opaque white and the white pigment forms a V shape running into the basal third of the rhinophores. The outer two-thirds of the rhinophores are bright orange red with a thin, often broken, median white line. The red pigment extends farther basally on the outer side of the rhinophore than on the inner side. The anterior margin of the foot is blue.

Thuridilla vatae is quite similar in colour to T. albopustulosa and both species are unique among species of Thuridilla in having connections between the lateral and posterior pericardial vessels. According to Gosliner, the radular teeth of T. vatae appear to be more finely denticulate than those of T. albopustulosa and the penial papilla of one specimen of T. albopustulosa had a constriction in the middle of its length. At present, it is not known whether this is a consistent difference between the two species.
Aspects of the coloration of T. vatae differ consistently from that of T. albopustulosa. In T. vatae, the ground color is a dark gray to black while that of T. albopustulosa is blue. The parapodia of T. vatae are ornamented with black and yellow spots, while those of T. albopustulosa are white or cream. In T. vatae, white pigment covers most of the length of rhinophores and only the apex is red. In T. albopustulosa, the majority of the rhinophores are red rather than white. In T. vatae, the red pigment is a solid transverse band, while in T. albopustulosa there are median white patches or a line within the band.

Reference:
• The genus Thuridilla (Opisthobranchia: Elysiidae) from the tropical Indo-Pacific, with a revision of the phylogeny and systematics of the Elysiidae. Proceedings of the California Academy of Sciences 49(1): 1-54.

Authorship details
Rudman, W.B., 2003 (July 3) Thuridilla albopustulosa Gosliner, 1995. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/thuralbo

Related messages


Thuridilla albopustulosa from Indonesia

May 4, 2005
From: Roberto Sozzani

Dear Bill,
this is a Thuridilla albopustulosa from Indonesia, for your database.

Locality: Sangeang island, Indonesia.Depth: 12 metres. Length: 15 mm. June 2003. Sand and coral slope. Photographer: Roberto Sozzani

Best regards
Roberto Sozzani
www.robertosozzani.it

roberto.sozzani@fastwebnet.it

Sozzani, R., 2005 (May 4) Thuridilla albopustulosa from Indonesia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13676

Dear Roberto,
Considering the colour variation in this species it is good to get another photo of it
Best wishes,
Bill Rudman

Rudman, W.B., 2005 (May 4). Comment on Thuridilla albopustulosa from Indonesia by Roberto Sozzani. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13676

Thuridilla albopustulosa found Southern Queensland

March 8, 2005
From: Gary Cobb


Hi Bill and everyone!
While diving at Pinnacles Noosa on Saturday I found Thuridilla albopustulosa. Because of the surge I lost the animal and only got two shots one out of focus. Still it is now recorded here on the Sunshine Coast Queensland, Australia. Is this the first time recorded in Australia? It was very beautiful.

Locality: Noosa, Queensland, Australia. Depth: 12 meters. Length: 25 mm. 05 February 2005. Open water. Photographer: Gary Cobb

That makes 192 species here recorded.
Cheers
Gary Cobb

gary@nudibranch.com.au

Cobb.G, 2005 (Mar 8) Thuridilla albopustulosa found Southern Queensland. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13292

Dear Gary,
Yes I pretty sure this is Thuridilla albopustulosa and I don't know of any published records from Australia, so I guess this is the first record.

Can I make a general request when people are filling in the new locality data form. Can you please put the Month in words in the format suggested. 05-02-2005 means 5 February 2005 to Australians but 2 March 2005 to those from USA - and in the rest of world some go one way, some the other - which means I haven't a clue.

Best wishes,
Bill Rudman

Rudman, W.B., 2005 (Mar 8). Comment on Thuridilla albopustulosa found Southern Queensland by Gary Cobb. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/13292

Thuridilla albopustulosa from the Philippines

March 24, 2004
From: Paul Osmond

Dear Bill
I believe this is a species of Thuridilla which we found on the wreckage of a Japanese WWII Transport at night off the coast of Malapascua Island in the Philippines on March 6th 2004.

The animal was approximately 20-25mm in size and it was found in about 4-5 metres of water. It is certainly very vividly marked which makes it even annoying that I can't identify it for myself...
Thanks,
Paul
www.deepseaimages.com

marriard@deepseaimages.com

Osmond, P., 2004 (Mar 24) Thuridilla albopustulosa from the Philippines. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/12512

Dear Paul,
This is Thuridilla albopustulosa, which ranges from a form with white-cream raised spots, as its name 'albopustulosa' suggests, to animals like yours in which the raised spots have merged into rounded ridges. It is found throughout the Indo-West Paciic from Japan across to South Africa
Best wishes
Bill Rudman

Rudman, W.B., 2004 (Mar 24). Comment on Thuridilla albopustulosa from the Philippines by Paul Osmond. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/12512

Thuridilla albopustulosa from Japan

November 16, 2003
From: Yukari Sato

Hello Dr.Rudman,
I have found this animal, which I think is Thuridilla albopustulosa, at Zushi, Sagami bay, Japan. It is one of the sea slugs which I love very much. It grows to about 20mm. I am happy if you have any comments.

All photos are from Zushi(near Hayama), Sagami Bay, Japan
Upper right: 8 Jun 2003, Depth: 27m. Size: 15mm.
Lower left: 4 May 2003, Depth: 20m, Size: 7mm.
Lower right photos: 27 April 2003, Depth: 20m, Size: 12-15mm.

Best regards,
Yukari Sato

yuks@cg7.so-net.ne.jp

Sato, Y., 2003 (Nov 16) Thuridilla albopustulosa from Japan. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/11397

Dear Yukari,
It is a beautiful animal. I am particularly interested in the animal alongside that you photographed in April. It does not have the typical white spots but I agree that it appears to represent a colour variant
Best wishes
Bill Rudman

Rudman, W.B., 2003 (Nov 16). Comment on Thuridilla albopustulosa from Japan by Yukari Sato. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/11397

Thuridilla albopustulosa from Japan

July 6, 2003
From: Fukuyo Yoshinori

Hi Dr.Rudman,
This Thuridilla albopustulosa was seen at Osezaki, Izu Peninsula, Japan, in March 2003.
Depth: 15m
Length 30mm

Fukuyo Yoshinori

fox@vcs.wbs.ne.jp

Yoshinori, F. , 2003 (Jul 6) Thuridilla albopustulosa from Japan. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/10383

Thanks Fukuyo,
This is another new species for the Forum. I see Keiu Suzuki has a photo of a small specimen from Osezaki in his book on the Opisthobranchs of Izu Peninsula, but it is apparently not common in mainland Japan.
Best wishes,
Bill Rudman

Rudman, W.B., 2003 (Jul 6). Comment on Thuridilla albopustulosa from Japan by Fukuyo Yoshinori . [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/10383