What is this Coral?

[marie]

I believe Siderastea has larger calices (between 2-4mm) and have tentacles not an actual extended polyp like porites.
Porites has a smaller calice (1-1.5mm in diameter) and polyps that are similer to montiporas.
To me the photos don't look anything like a porites but then again I'm not a coral taxonomist....and I didn't stay in a holiday express inn last night

*edit* siderastrea also appears to be a very common coral in the atlantic, not so much in the pacific which would explain why some of us aren't very familiar with it

[justinl]

Siderastrea is a very common coral in the wild (so a hitcher is very plausible), but for whatever reason, it just isn't sold commercially very often.

Porites is a SPS. from the pic, I would say the corallites on your coral are relatively big... much bigger than porites porites at least, so i would rule that one out. Siderastrea is definitely a plausible guess, but in all fairness it is just an educated guess. A lot of very unrelated corals look alike and identifying them can be tricky. For example, you might never be able to tell a specimen of acan from a favid like a blasto or micromussa without close examination of the skeleton (which you might never see until it's dead). Applies here too (obviously, given the debate goin on).

as for the Xmas tree worm thing, the worms can live on a lot of different corals, but you have to keep in mind that the term "xmas tree worm" is actually a broad term that designates a whole (very misunderstood) complex of species. In the wild, it seems that they are obligated to live on some kind of live coral (or else they get eaten), but in a tank where nothing will bore into their calcium tube, they *probably* could survive anywhere from rock to dead coral. Greg, the ones you see on the rocks probably just technically aren't xmas tree worms... but hell, a lot of the feather duster worms do look a lot alike. past that you can't really generalize and say that they must live on porites and porites alone... because it just isn't true. see link below. it's a good short read and clears this issue up in my mind.

http://www.advancedaquarist.com/issu...002/toonen.htm

[Snappy]

Originally Posted by justinl

Greg, the ones you see on the rocks probably just technically aren't xmas tree worms...

Actually yes they are, I don't want to sound like a jerk but I think I have enough experience both in this hobby and as a diver to know the difference between a feather duster and a xmas tree worm. They are very commom in orange, red, blue and grey in the Puerto Vallarta area and host in solid rock. They bore a hole just like they do in the corals. I recommend you go diving at Los Arcos for example and then come back and tell me they aren't xmas tree worms.
But if you go can I come too? We'll have a blast..

I've never even heard of this species...how does it differ from Porites? It looks VERY similar. If this is true (and I doubt it very little), then I bet there are A LOT of misidentified Porites out there!

It is an LPS and Porites is SPS, the polyps are completely different. As they get bigger the difference if more prodominant.
Here is a picture (magnified) I just took of mine. At night the regular polyps start to retract and if you look closely you'll see sweepers starting to extend in a few places. In a few more hours it will be a mass of tenticles.

[Oscar]

Originally Posted by justinl

Porites is a SPS. from the pic, I would say the corallites on your coral are relatively big... much bigger than porites porites at least, so i would rule that one out.

The coralites on the coral in questions are 2-4 mm across. I have not spotted any sweepers yet but I will keep looking.

It is almost 7:00 am, the LED moonlights are on and the tank receives some incidental sunlight in it's location. The coral is fully extended, not retracted as in the 2nd photo I posted.

The mystery continues.

Are we having fun yet?