January-July 2023 PODs

Bill’s “Pictures of the Day”

from the first part of 2023

To start the year here is a pic of a long nosed hawkfish (something we used to shoot before we got caught up in the latest, bestest, rarest critter) from our recent Indonesia trip.

Here is a nice little Pseudobiceros bedfordi otherwise known as the Persian Carpet Flatworm. This guy was from our recent trip to Banda on the Samambaia. Here he is on the black felt stage. These are interesting guys. They have 2 penises which they use to penis fence, trying to impregnate their opponent while remaining un-impregnated themselves. Read “Hermaphrodites duel for manhood” for more info on this.

Here is a nice little skunk anemone fish, Amphiprion sandaracinos from the Banda Sea. Anemone fish are interesting in that they live in an anemone, the largest fish of the group is the female and she actively keeps the smaller males from changing to female. The only way the small males get their genes into the pool is to live longer than the big guys. There is a lot of study on how and why sex change happens, see Ross,R., Environmental Biology of Fishes, 1990, p. 81 for an interesting but complex explanation.

On our recent trip to Indonesia on the Samambaia we found this nice little Gymnodoris (don't know the exact species; there are 3 or 4 that look the same to me). I was playing around using a focus light off camera to side light the nudibranch. Not sure if I like it but it kind of looks like he is glowing.

Nudibranchs when they lost their shells needed some way to defend themselves from being lunch. Some get their defense from toxins in the food they eat, some modify a molecule from the food to make a toxin and some make their own (biosynthesis). The Goniobranchus coi, here sitting on a black stage can make an interesting diterpene that MIGHT have some anti-cancer properties. It always amazes me that sea creatures can effortlessly make complex compounds which will take very skilled chemists in the lab months to make.

Here is a nice little blue dart fish from our recent Indonesia trip. There were tons of his red cousins but the blue ones were much rarer and often quite deep (> 100 feet). Usually when you get close they dive into their holes but this guy was quite comfortable staring me down. They are nowadays quite common in salt water aquaria and are now able to be raised in tanks. In tanks at least the male does the majority of egg watching for the 4 days of incubation. Courtship seems complex but you can read about it and decide for yourself: Aquaculture, 2014, Captive Spawning and embryonic development of Nemateleotris decora, Madhu et al, p. 1.

Here is a nice little Halgerda terramtuentis (gold lace) from our recent trip to Hawaii. These were pretty much the only nudibranchs I saw on the trip. These guys make lots of cool molecules including halgerdamine, which is being studied for its antineoplastic potential.

We went diving last weekend and it was cold (50-51F)  and very green with pretty crummy vis. We did a single "blue" water dive and below about 80 ft it cleared up a bit. Here is a nice little jelly that we saw at about 90 feet.

Another jelly from last week's dive, this one with a hitchhiker.

I have a new stage that is a lot more optically imperfect than some of the older ones. This one is a bit wavy and has a bunch of what look like bubbles in the glass. Here is a nice little Hermissenda  sitting on the stage from last week's cold and green dive.

Here is a nice little Ceratosoma brevicaudatum from our recent trip to South Australia. These guys were quite common and they have a unique ability to make defense molecules, and not simply use the ones that their diet contains. Here (inset) is one compound. Here he is sitting on the "new" glass stage.

New camera (OM-1), new housing (AOI), new lens (Olympus 90 mm macro). We went out Saturday on our favorite boat with Captain Jim and a bunch of friends. Trying out the new system before our Anilao trip. Here is a nice little local nudibranch Ancula gibbosa. Here he is sitting on the new glass stage (still not sure if I like it). The red color of the background is because the stage was directly in front of a bunch of red gorgonians.

On our recent trip to Anilao, we found a bunch of egg or false cowries. Here is a Cavanagh's (I think) sitting on a black felt stage. These guys are masters of mimicry, reproducing the host colors and textures amazingly well.  How they do this is complicated; see Sánchez JA, et al., 2016. The masquerade game: marine mimicry adaptation between egg-cowries and octocorals. PeerJ 4:e2051 for more details.

We went diving with friends on Sunday on the Giant Stride. Cold but fun. Here is a nice little Simnia sitting on the black telescope stage. These are the first I have seen in a while. Simnia exhibit “alimentary homochromy” which means they get their color from what they eat.

On our dive last Sunday with friends on the Giant Stride, we did some dives at the Garden Spot. Near the reef in the sand were numerous Phoronids poking their heads up (not really their heads) to catch some food. It turns out according to Ronan (From UCLA) , Biological Bulletin, 1978, that these guys's fecal pellets can be one of the major food sources for Hermissenda nudibranchs. 

Here is a nice little Platydoris pulchra from our recent trip to Anilao, sitting on the black telescope felt stage. For this view I was able to get the camera almost perfectly parallel to the stage. These guys are specialized sponge eaters and have evolved together with their prey. In areas where there are lots of different kinds of sponges, Platydoris is an opportunistic feeder eating anything he can find, while in areas with a low number of sponge types, they can become single sponge type obligate. For details see Megina, J. Moll. Studies, 2002, p 173 where they did lab based feeding studies in the lab. Different sponge communities from different locations caused Platydoris food choices to be different in the different areas, but enough blathering.

During our Anilao adventure I actually used a snoot (after being a snoot denier for years). Here is an attempt (not very good I think, but still a try) to use the snoot on a nudibranch on stage and capture a bit of reflection. Artsy, shmartsy.

Here are a pair of robust ghost pipefish from our recent trip to the Philippines. Their name suggests that they are pipefishes but they are not. Unlike real pipefishes (family Sygnathidae, ghosties belong to the family Solenostomidae), in the ghost family, it is the female that broods the eggs, holding them in a pouch made from a set of fused fins. In this pair, the female is the larger, the male is smaller and skinnier.

Here is a nice little fire dart goby, Nemateleotris magnifica from our recent trip to Anilao. I love these guys and their cousins the purple ones. These guys mostly occur in pairs and if you get too close they shoot into their holes very quickly (and mostly never come back). They are very susceptible to a variety of copepod infections and if you want to not enjoy dinner, read Biasola, G., J. Parasitology, 1979, p 662 (ping me if you want a copy).

Here is a nice little Goniobranchus collingwoodi sitting on the black telescope felt stage from our recent trip to Anilao. Who says Terry Gosliner has no sense of humor? A recent paper describing the DNA of a series of Goniobranchus is entitled "Battle of the Bands, systematics and phylogeny of white Goniobranchus with marginal bands", ZooKeys, 2022, p. 169. Lots of DNA BS in there and lots of definitions of clades (common ancestor) but not much in the way of interest to a chemist (i.e., how do they make the colors for example). 

Here is a nice little Hypselodoris (sp. 23?) from our recent trip to Anilao. Here he is sitting on the black telescope felt stage. Notice that the left rhinophore is bifurcated either from a development mistake or the result of an injury.  Rhinophores allow nudibranchs to "smell" their environment and flee downstream from a predator or follow some food upstream. Bilateral symmetry suggests that two rhinophores are useful for navigation, but in a paper by Wyeth (J. Exp. Biol, 2014 "One Rhinophore likely provides sufficient sensory input for odour based navigation") they show in a series of pretty neat experiments that a single rhinophore is good enough for navigation. If you want a copy, let me know.

Wire coral shrimp are pretty easy to find. This guy (Izucaris masudai) lives on a wire coral, but is associated not with the coral but with the anemones living on the coral. These guys are hard to find, hard to light, hard to get head-on so here is a shot from the side. This guy was deep in Anilao (100 ft) and during the day the polyps were in.

Just a nice little feather duster worm, with cool colors.

Here is a nice little Goniobranchus kuniei from our recent Anilao adventure. Sitting on the black felt stage. These guys are well known for generating, or eating and sequestering compounds that have potential use in chemotherapy.

Here is a nice little Pseudoceros liparus, a flatworm from our Anilao adventure. Sitting on a black telescope-felt stage. The bright colors may be for various reasons, mimicry of toxic guys, toxicity itself or maybe they just want to look cool. The blue color from many of these flatworms typically come from their food with minor chemistry being done by the worm itself. Often the blue color has some type of cytotoxicity (good for treating cancer) (see Schupp et. al., Organic Letters, 2009, p.1111 for some chemistry of flatworm colors).

Here is a nice little well camouflaged crinoid shrimp from Anilao. These guys live life on a crinoid. Crinoids are interesting, they are filter feeders and they filter feed with their food groove facing downstream. Seems backwards to me. During current reversal or surge their food grooves face upstream. It turns out (Holland, Upstream and Downstream capture in crinoids, Bio Bull, 1987, p 552, let me know if you want a copy) in the lab at least with brine shrimp as the food, the upstream capture was about half as efficient as the downstream. 

Here is a nice little Triopha maculata from our dive with friends on the Giant Stride on Saturday. Sitting on the telescope felt stage. These guys are interesting in that they have a set of neurotransmitters, that are perfect homologues of the transmitters that allow Tritonia to swim by wiggling and flexing the body. The Triopha however does not swim, but only crawls. The authors of an intriguing paper (Newcombe, J. Comp. Physiology, 2007, p. 425, ping me if you want a copy) suggest that the crawling transmitters came first then got co-opted to become the controls for swimming. These guys (the authors) did a bunch of cool electrophysiology (hard as hell) experiments but the conclusions to me are not obvious.

Another week, another simnia. Diving with our friends on the Giant Stride.

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