Image courtesy of John Greenamyer
Milne Bay, PNG
Freeze Frame from Video circa 2008

Hypselodoris jacksoni Wilson & Willan, 2007

Until John's sighting of Hypselodoris jacksoni (Courtesy of Dave Mullins) in Papua New Guinea it had a fairly limited distribution in the south-western Pacific Ocean being reported only from the subtropical and temperate waters of the Australian east coast.

Hypselodoris jacksoni (Courtesy of Bill Rudman's Sea Slug Forum)

"... has a relatively high body profile, an elongate body, and a narrow mantle skirt. The gill pocket forms a high raised collar as in H. krakatoa

The background color of the mantle and the foot is translucent greyish often covered in part by opaque white. There is an open reticulation of relatively thin dark brown to black lines arranged in a symmetrical pattern down the mantle. There is usually an irregularly shaped and slightly raised milky yellow patch in each of the spaces formed by the reticulation. A similar color pattern is found on the sides of the body and foot. There is a thin orange band around the edge of the mantle. This band is absent on the edge of the foot.

The gills are held erect. They are triangular in cross section, translucent, with an orange line up each edge. The rhinophores are an intense orange with a pale whitish tip..."


Wilson, N.G. & Willan, R.C. (2007) Hypselodoris jacksoni, a new species from the south-western Pacific Ocean (Nudibranchia: Chromodorididae), with a discussion on intraspecific variation in mantle glands in Chromodoris willani Rudman, 1982. Zootaxa, 1549: 29-42

Dave Behrens
Sammamish, WA 98074
Jan. 2024
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Linda Blanchard, John Greenamyer , and Kevin Lee
Recognition Ceremony Doto Greenamyeri
Orange County Underwater Photographic Society monthly meeting
July 14th, 2015

John Greenamyer has been diving some thirty years with a macro u/w photography pursuit using both still photography and video. His favorite diving areas are PNG and Indonesia with an emphasis on PNG, especially the Milne Bay region so popularized for its "muck" photographic opportunities. On many of these trips, he was in the company of Roger Steene, Neville Coleman and Ali Hermosillo on the CHERTAN!

John has been kind of a mentor to me when it comes to super macro sea slug videos! John is also a great supporter of the site and I look forward to diving with him again in the future!

Congratulations John, your naming is an honor richly deserved!

Michael Miller
San Diego, Calif
Jan, 2015

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From left to right, Terry Gosliner, Angel Valdes, Dave Behrens La Jolla, Calif.

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