Charlie's Diving Blog: Eighth blog from 55 dives in 17 great days and nights of diving at Crystal Blue Resort, Anilao, Philippines 1-20-2-5-2024

This blog is on the wonderful Nudibranchs, sea slugs, and flatworms I saw during my wonderful dives at Crystal Blue Resort. By the way all sea slugs are nudibranchs (naked lung, the pretty flower like structure you see on their backs which are their gills for breathing), flatworms are not mollusks like sea slugs, they are in their own phylum. I read that there are about 1,200 species of Nudibranchs in the Philippines, I've gathered photos of 50 different nudibranch species and photos of six sea slugs and marine flatworms. Relax, I won't attempt to show you all of them here, if you want to see more than are in this blog, please go to: https://photos.app.goo.gl/KA776FGRq58tLTNm6 Below is a photo of the most bizarre nudibranch, indeed, one of the most bizarre animals, I've ever photographed. Here's the thing, it is virtually invisible except for a tracework of fibers that effectively frame the otherwise invisible nudibranch. I couldn't believe there was anything there to photography initially, but when Jhomer points emphatically and says "ughawha" in a burst of bubbles, you shoot! Below is Melibe colemani, aka Ghost Nudibranch, it's the latticework you see in the center of the photo. If you want to learn more about this truly bizarre animal, google melibe colemani or please go to: https://www.google.com/search?gs_ssp=eJzj4tFP1zc0Ms0zKkmvMjZg9OLPTc3JTEpVSM7PSc1NzMsEAJKKCfw&q=melibe+colemani&rlz=1C1SQJL_enUS874US875&oq=melibe+&gs_lcrp=EgZjaHJvbWUqBwgDEC4YgAQyBggAEEUYOTIHCAEQLhiABDIHCAIQLhiABDIHCAMQLhiABDIHCAQQABiABDIGCAUQRRg8MgYIBhBFGDwyBggHEEUYPNIBCDY1ODdqMGo5qAIAsAIA&sourceid=chrome&ie=UTF-8

Below is an Elisabeth's Chromodoris Nudibranch. The bright colored "flower" on the left is the reason these sea slugs are called nudibranchs from latin for "naked lung" its actually the sea slug's gill, it can be temporarily retracted for protection of the nudibranch is threatened. On the right on the nudibranch's two similarly brightly colored rhinophores, frequently mistaken for eyes, they are taste or chemical receptors. Below:

Next is the very strange Gold Lace Nudibranch, its black spotted gray rhinophores are in the foreground, its similarly colored flowery gills with black spots on in the back of the photo. Below:

Below, Bus Stop Chromodoris nudibranch:

Above: Willan's Chromodoris on a tunicate. Below: Coleman's Chromodoris grazing in front of a colony of clear/translucent tunicates with blue spots. Nudibranchs eat sponges, anemones, corals, hydroids, bryozoans, tunicates, algae, and sometimes other nudibranchs.

Above: A Miramira aleni nudibranch, it looks like a bit of soft coral. If you look closely, you can see its rhinophores to the right and left of its "face" in the foreground. It's probably grazing on the small yellowish oval tunicates on the bottom around it. Nudibranchs are hermaphrodites, they each have both male and female sex organs. Below is a closeup of a Nembrotha chamberlaini nudibranch where you can see the detailed structure of its rhinophores. The second photo is a pair of them mated up, joined with a "docking station" to exchange sperm. Below:

Below: A Chromodoris joshi nudibranch with a small fish resting on its side right above its flowery gill.

Above: Wonderful Blue Dragon Nudibranchs, aka Pteraeolidia ianthina Below: Lined Nembrotha

Above: Hypselodoris tryoni Below: Sky Blue Phylidia

Below: Beautiful Risbecia

Above: Safron Noumea The first ten days I was at Crystal Blue Resort was their annual Critterfest. Below is a picture of this year's Critterfest group (can you spot me?). One of the women, just right of center, put on our Critterfest participation shirt backwards so that you can see the cute Pikachu nudibranch photo on the back. I was fortunate to not only see and photo a Pickachu (aka Thecacera pacifica) ibut also a pair of amorous mating Pikatus, you can see they are linked by their "docking ports", bet you've never seen that before!! Below: