Marionia sp. 6

Image courtesy of David Cowdery
Anilao, Batangas, hilippines

Image courtesy of Constantinos Petrinos
Marionia sp. 6 (Undescribed, NSSI 2nd Ed).

Common, yet undescribed, this large Marionia is brownish-green with white transverse lines on the dorsum. The brownish-green becomes a network of spots surrounded by white on the sides of the body and secondary gills. The gills are highly branched. The frontal vale has 3-4 pairs of simple or divided velar tentacles.

This species is active at night when it feeds on the soft coral Lemnalia sp. And is preyed upon by by the carnivorous dorid, Gymnodoris aurita. G. aurita as can be seen in a photo to the left taken by Constantinos Petrinos, feeding on Marionia sp. 6.

It reaches 100 mm in length and occurs throughout the Western Pacific Ocean.

Dave Behrens
New Braunfels, TX
Jun., 2023
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Dave Cowdery is a retired bio-medical Engineer and is the inventor of the Alumina/Titanium hermetic feedthrough (1970) for implantable bionics and the first to introduce a Titanium casing. This invention created the first bionic implant (pacemaker) with a service life that could be measured in years rather than months and is the basis for todays huge multi billion dollar bionic industry. David's pacemaker invention and his critical contribution to the launching of the Cochlear hearing implant has recently been recognised in two authoritative books ( "Innovative and Intelligent Bioceramics in Translational Medicine" and "Alumina Ceramics-Biomedical and Clinical Applications").

David is a Divemaster with over 5,500 dives experience and is based near Byron Bay in Australia. David is also a keen competitive road bicycle rider covering over 400 km most weeks. Photographic equipment used Nikon D800 camera with DS160 substrobes.

During a night dive at the recently held nudibranch conference at Anilao, Dave came across a magnificently coloured Chromodoris joshi, the first one he had ever sighted. Dave thought his night was complete when he then found the undescribed Marionia. Dave described the huge colourful animal as being about 15cm long, probably the longest Marionia he has ever seen.

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

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