Cozumel Creature ID Help

[sapphire]

Hi! Just back from Cozumel, getting all my pictures ready to post... but I am having a hard time identifying this urchin... even the DMs didn't know what kind it was. Can anyone help??

 

[archman]

Oh you lucky *******, you've got a pic of the "Magnificent Urchin" Astropyga magnifica. It's related to Diadema (same family), but likes deeper water. The giant anal cone is distinctive. I have yet to see one myself, and I'm supposed to be an expert. My jealousy runs deep. Can you post the depth, specific habitat (coral, grass, sand), and where exactly you saw this sucker? Any others nearby?

 

[sapphire]

OK - I'll try. I have not downloaded my dive computer yet, so my guess as to depth is in the 45-55 foot range. I have some video of this too, as the videographer was with us on this dive (she had never seen one before either!). The location was San Francisco Reef, and it was in a sandy area at the top of the reef, as you can see huddled up against this sponge but surprisingly out in the open for an urchin in the daytime, I thought. I didn't see any others.

Is what you call the "giant anal cone" what I call the "eyeball"?? It was waving that thing all around, it felt like it was "watching" me while I took its' picture!
I saw the Magnificent Urchin in my "Reef Creatures" but the photo there didn't look exactly like this one so I was unsure...

Thank you for the ID! Hurry on down there and find that guy before something eats him, he is a daredevil!

 

[Dee]

I've seen several of those in Cozumel. Didn't realize they were deep water critters.

 

[justleesa]

Cool! Lucky you!

 

[archman]

I've seen several of those in Cozumel. Didn't realize they were deep water critters.

They're not deepwater (technically defined as exceeding 900 ft), they're just deeper. Astropyga likes it around 65-150 ft, putting them within recreational dive limits. They're just rare as sin. Nobody knows why.

Is what you call the "giant anal cone" what I call the "eyeball"?? It was waving that thing all around, it felt like it was "watching" me while I took its' picture!
I saw the Magnificent Urchin in my "Reef Creatures" but the photo there didn't look exactly like this one so I was unsure...

Yeah the anal cone looks like a bullseye. Diadema also has one but most people don't notice it 'cuz it's the same colour as the animal (dark grey/black). I'm curious as to what the Humann book says about this species... I wasn't aware it was in there. Then again I use a different book.

 

[onbelaydave]

I've seen several in 20-30' in front of the Villablanca. I've read of many reports of them being seen in the shallows at Coz over on D2D's site and it got me wondering; whether the Coz currents are depositing the eggs in the shallows until they mature and migrate to deep water ? Things that make you go hummmm?

 

[Scubakevdm]

Hey! That's fantastic Jennifer, I have never had anything wave a giant anal cone at me. Hope you had a great trip.

 

[H2Andy]

Hey! That's fantastic Jennifer, I have never had anything wave a giant anal cone at me.

muhahahaha... you just haven't lived, i guess

 

[archman]

Has anybody seen these things in clumps (more than one)? If so, take a picture and post it pLeAsE!!

it got me wondering; whether the Coz currents are depositing the eggs in the shallows until they mature and migrate to deep water ?

These things have planktonic larvae, like most echinoderms. So they'll be up in the shallows anyway. Baby urchins tend to hide in holes, with little/no regard for depth.

Two questions about them being seen in shallow water.
1. Were these daytime or night dives? Most urchins come out at night, so they're easier to spot.
2. Did these sites have (or were adjacent to) a pronounced slope/wall? They can vertically migrate a lot quicker.