Okenia japonica
Baba, 1949

Suborder: DORIDINA
Family: Goniodorididae


This species was previously known only from a few records from Japan.


3 specimens, 14 April 1983, Site 2.66, Round Is. (W), Mirs Bay, 3-6 m, AM C139013. Upper Photo: inset showing spiculate mantle - B.W. Darvell, Lower Photo: on bryozoan prey - B.E. Picton.

This small elongate species of Okenia has small rounded papillae along each edge of the mantle. The mantle edge and the papillae are usually pigmented white, and there is a white band along the edge of each gill, but the rest of the body is a translucent whitish colour devoid of pigmentation. This species, up to 8 mm long, has been found on encrusting bryozoans [see message #5070] but more recently it has been reported on an erect ctenostome bryozoan of the genus Amathia [see message #12651]. A description of the radula is in a separate message [message #12651 ].

  • Baba, K. (1949) Opisthobranchia of Sagami Bay. Iwanami Shoten, Tokyo. 211pp + pls.
  • Rudman, W.B. & Darvell, B.W. (1990) Opisthobranch molluscs of Hong Kong. Part 1. Goniodorididae, Onchidorididae, Triophidae, Gymnodorididae, Chromodorididae, (Nudibranchia). Asian Marine Biology, 7: 31-79
  • Gosliner, T. M. (2004) Phylogenetic Systematics of Okenia, Sakishimaia, Hopkinsiella and Hopkinsia (Nudibranchia: Goniodorididae) with descriptions of new species from the tropical Indo-Pacific. Proceedings of the California Academy of Sciences, 55: 125-161.
  • Rudman, W.B. (2004) Further species of the opisthobranch genus Okenia (Nudibranchia: Goniodorididae) from the Indo-West Pacific. Zootaxa, 695: 1-70.
Authorship details
Rudman, W.B., 2004 (December 21) Okenia japonica Baba, 1949. [In] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/factsheet/okenjapo

Related messages

  1. Radula of Okenia japonica
    From: Bill Rudman, December 21, 2004
  2. Okenia japonica from Japan [1]
    From: Yukari Sato, November 14, 2003
  3. Okenia japonica from Japan [2]
    From: Yukari Sato, November 14, 2003
  4. Okenia japonica from of Hachijo Is, Japan
    From: Nishina Masayoshi, August 17, 2001
  5. Okenia japonica from Hong Kong
    From: Bill Rudman & Brian Darvell, August 17, 2001

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