Thecacera sp. 8

Image courtesy of Mike Bartick
Photo taken at Anilao, Batangas, Philippines

Thecacera sp. 8 undescribed

Thecacera sp. 8 (in NSSI), known by the boys in Anilao as "Pika Chus" was presented as a BOW in Week 768 on December 26, 2011. At that time it was referred to as Thecacera sp. 4 from "Indo-Pacific Nudibranchs. Since then we have discovered several more new species.

This species is externally similar to Thecacera sp. 5 (page 119 in NSSI). Don't confuse them.

Mike has captured this pair mating, an uncommon situation at best. In his photo we can clearly see the male and female genitalia within the engorged transparent genital papilla. As expected the two specimens are juxtaposed head to tail, each with the genitals on the right side of the animal. Each will transfer sperm to the other. See Video Link!

The blacked tipped rhinophores are this species ID character. It appears that specimens retract the fimbriate extrarhinophoral process during mating. Interesting.

We will be looking for this sharp looking species at the Nudibranch Festival at Crystal Blue Dive Resort in March. We have several openings and would love you help us add to the range of this species.

Dave Behrens
Sammamish, WA 98074
Feb., 2018
Send Dave email at

Mike Bartick shown here as managing editor for California Dive Magazine
Mike Bartick is a Marine Wildlife Photographer residing in Anilao, Philippines, with an insatiable love for finding unique marine life, observing and photographing its behavior and sharing his insight and knowledge with others. His curiosity and drive for first-hand experience has lead him across the globe in search of that special critter encounter. Mike is a widely published Photographer, writer and international speaker with work appearing monthly in international magazines, websites and internet publications. He also hosts photo clinics and seminars concentrating on the different aspects of Underwater Photography and the natural history of South East Asia and the Indo-Pacific.

Mikes Gear- Mike is currently shooting with a Nikon D7100 in a sea and sea housing. He uses Sea and Sea strobes and or INON Z240. Mike also uses the Retra Ultimate Snoot in many of his images to eliminate busy backgrounds and to halite his subject

Mike is regarded as an expert in his field and enjoys being in the water as much as possible and agrees that the next best thing to being there, is talking about his experiences.

Mike is the Photo-pro for Crystal Blue Resort i Anilao, Philippines. He hosts Photo and natural history workshops each month and is usually underwater.

Contact him by e-mail- at for more info or visit the Crystal Blue Resort Website where Mike is the GM.

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

Send Dave email at
© The Slug Site, Michael D. Miller 2018. All Rights Reserved.