August-September 2021 PODs

Bill’s “Pictures of the Day”

from August to September 2021

Here is a nice little Cuthona nana (if it is still that genus) that our friend Anastasia found on our dive in PV yesterday. He is sitting on a piece of shell. These are interesting creatures, since they eat a hydroid that is normally sedentary but are often found on hermit crabs giving the nudibranch a lot more mobility than if the hydroid was sitting still. There is an interesting paper (Rivest, Biological Bulletin, 1978, p 157) that describes the entire lifecycle and how mobility helps species diversity. It is fascinating that the simple idea of eating on the run so to speak can make a species more successful.

Here is a tiny (and I mean tiny) gammarid amphipod, found yesterday by Nannette and identified by the Canadians as the gold crusted Podocerus cristatus (most certainly incorrect but who knows). In any case, not the greatest shot; it was surgey and kelp was blowing around but here he is.

As many of you know, I love Spanish Shawls (Flabellinopsis). Here is one from yesterday.

Here is a nice little clown nudibranch sitting on my dichroic glass stage. The bubbles are actually in the glass.

Here is a nice little Cadlina limbaughorum sitting on the black telescope felt stage.

We went diving yesterday on our favorite boat, the Giant Stride with friends. My buddy Dana kept bringing me nudibranchs to put on stage including this nice little Porter's.

Here is another Cadlina, this one sitting on the dichroic glass stage. I have never seen a reflection like this before. All I can figure is that I was using a ring-flash with a second strobe on the side and somehow this is what happened.

Last Sunday was kind of surgey down below. Here are two of my favorite guys, Spanish shawls both hanging on for dear life. They wanted no part of posing on stage.

We went diving to the Farnsworth Banks (the backside of Catalina) on Sunday. Amazing amount of fishies there. When you start down you don't see the normal rock-looking reef but an amazing purple/blue everywhere. The purple blue is Stylaster californicus also known as purple hydrocoral. Here is a close up of some of the coral with some tentacles out feeding. There is a tiny commensal snail that has the same color; we are going on Monday to find him.

Because I knew we were going to see coral I brought along a square tube fun house mirror. Here is a close up of a piece of coral with associated reflections.

The Phoronopsis above was shot at Catalina; we were looking for mantis shrimps but they saw us first and stayed under the sand. But I did find this pretty little Phoronid which was first described in a delightful paper from 1930s; the language is quite interesting and not very "Scientific".

Here is another creature from our Saturday dive at Catalina on the Giant Stride. This is a Navanax which is a predator of sea slugs (but we don't see many slugs at this site). Navanax are hermaphroditic like nudibranchs (Navanax are head shield slugs) and you have to love a paper that has a title Sperm trading and sex roles in the hermaphroditic opisthobranch sea slug Navanax inermis: eager females or opportunistic males? It turns out that actuality trumps theory in this regard. They have interesting mating ideas: "Individuals were observed to attack their mate at least once in 50% of the mating sessions. Attacks involve the explosive expulsion of a pharyngeal ‘basket’ that partly or wholly sucks in the target. Animals also attacked individuals of the same size as themselves, but were not able to swallow them”.

Many of you knew Marianne and many more knew of her. She was one of our dearest friends in the world and sadly she passed away last weekend. This was one of her favorite photos. Marianne my friend, rest in peace.

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