Mexichromis trilineata

Image courtesy of Jim Black
Ambon, Indonesia

Image courtesy of Jim Black
Ambon, Indonesia

Mexichromis trilineata (A. Adams & Reeve, 1850)

This beauty is quite variable in coloration, some specimens having only a single dorsal line. The norm however is what we see here in Jim's photo - white or yellow marginal band, and three yellow to orange dorsal lines (hence the trivial name - trilineata), edges with white. The gill and rhinophores are a deeper red-orange.

This species was formerly included in Pectinodoris, but due to its unique radular morphology is now lumped with Mexichromis and species previously assigned to Duvilledoris.

Jim was fortunate enough to capture this shot with egg coils, which contain pink eggs and are attached to the substrate by the edge of the coil, like species of Goniobranchus and Glossodoris.

Image courtesy of Michael Miller
Ambon, Indonesia

This species which is common throughout the Western Pacific Ocean feeds on the sponge, Dysidea sp seen at left.

Thanks for sharing Jim and Mike !

Dave Behrens
Sammamish, WA 98074
July, 2019
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Jim on location at Raja Ampat, 2017

Jim Black Retired from US Airways, and now after a merger, American Airlines with 37 years service as a pilot. Jim retired as Captain flying an A330 Airbus Internationally. Diving since 1970, with close to 8000 dives now. Currently shooting a NIkon D800E in a Subal Housing with Ikelite strobes.. Jim uses a Macro Mate, and a Nauticam SMC and its Multiplier for super macro work.

Jim's photography has been featured in a number of books and publications including Helmut Debelius' Nudibranchs and Sea Snails of Gosliner, Behrens and Williams Coral Reef Animals of the Indo-Pacific. A photo of Jim petting a shark in "Sleeping Shark Caves" off Isla Mujeres Island, Mexico, taken by Amy Foster his significant other, recently appeared in Dave Behrens' Diving Guide to Cozumel, Cancun & The Riviera Maja.

Jim has also been a major contributor to (1) the New Indo-Pacific Nudibranch and Sea Slug Identification book by Gosliner, Valdez, Behrens (NSSI),(2) Tropical Pacific Reef Creature Identification by Humann & DeLoach,(3) Nudibranchs Encyclopedia by Neville Coleman,(4) Reef Fishes of the East Indies by Gerald Allen and Mark Erdmann, And many other publications.

Jim has been a solid supporter of the Slug Site since day one. His countless contributions put him near the top of the list of photographers who have greatly expanded our knowledge of sea slugs. There are a lot of kids in the formative stage of their education who are getting their first introduction to our sea slug friends via the great photographs Jim and other contributors have made to the site. My hat is off to Jim for making this presentation possible!

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

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