As Phyllodensium Nudibranchs are uncommon, bizarre and attractive at the same time, they always make a good Blog post. Specially when they are found in numbers. Having blogged some weeks ago already about the Solar powered Nudibranch, it’s today the turn of the Kabira Phyllodensium (Phyllodensium kabiranum). As they are very well camouflaged when feeding on Soft Corals, they are very hard to spot – but once you found them, they make a very attractive subject. Specially, when they are isolated from the soft coral, like this one in the picture. At the moment we are finding 5 of them at Nudi Retreat – but we are also seeing them at some other Dive Sites here in Lembeh Strait.
The blue highlights in its brown tentacles make it already very attractive – but when you pass the right moment of the surge moving all it’s cerata to one side, you can see its beautiful orange base. Keep looking within Heteroxenia and Xenia corals and you might find one.
It seems to me, that we see a lot of Phyllodensium Nudibranchs at the moment. We encountered 4 different Types only yesterday – and 3 Solar Powered Nudibranchs (Phyllodensium longicirrum) on a single dive at “Tanjung Kubur”. The one you can see on this picture was a smaller one. As i was preparing for the shot, i realised, that there was a little fish hiding between the Cerata (tentacles) of the Nudibranch. It turned out to be a little Wrasse seeking shelter within the “arms” of the Solar Powered Nudi. This shot was taken in a brief moment, when the Wrasse came out of its solar powered home.
Even though we also saw a Blue Ringed Octopus, 2 Ambon Scorpionfishes, a Flamboyant Cuttlefish, Hairy Shrimps and other cool Critters on this dive at, the little Wrasse hiding in the Nudibranch was still my personal favourite of this Dive.
We were 6 Divers and had Johan, Stenley and Marnez as Guides with us.
The Solar-Powered Nudibranch (Phyllodensium longicirrum, Solar-Powered Phyllodensium, Long-Cirri Phyllodensium) is one of the celebrities among the Lembeh Nudibranchs – everybody knows it and everybody likes to see one. The Solar-Powered Nudibranch (SPN) grows to 15 cm in size and is the biggest member of the phyllodensium nudibranchs. As other members of this group, the SPN farms Zoocanthellae algae in its Cerata (tentacles) to create energy through photosynthesis. The flat Cerata have a big surface an therefore lots of space for the algae patches that are separated into individual “solar panels” (that are visible as little brown spots).
The SPN feeds on leather corals of the type Sarcophyton trocheliophorium and stores their toxins to taste bad for potential predators. It usually hangs out around a leather coral until it has consumed it.
Best place to see SPN in Lembeh: Most coral dive sites like for exemple Makawide, Batu Sandar but also Muckdives like Aer Bajo or TK sometimes have SPN.
Photo Tip: Use a wider lens (60mm or wider) as the SPN is relatively big in size. For a big SPN sometimes even Wide Angle can be a good option. The Cerata swing to side to side with the surge … so a good technique is to position yourself in front of the head, prefocus on the rhinophores and wait for a moment when they are both visible.
No doubt: Diving in Lembeh is good all year round and there is always a lot to see. But still it is never the same and everytime you come you see some things more frequently and others less frequently. The last days i realized, that there are several members of the Aeolid Nudibranchs (the rather hairy ones like Flabellinas or Phyllodensium) aggregating. I have seen now 4 different species gathering for mating (i suppose) in 2 days of diving.
Specially the Phyllodensium is a very cool group of Nudibranchs as most of them store symbiotic zooxanthella algae in their tentacles to gain energy through photosynthesis. Plus they are very well camouflaged as they often exactely match the corals they live on – so this makes it even more special if you can spot them. There are many different species of this group to see here in Lembeh Strait … besides hundreds of other nudibranchs and thousands of other cool critters.