Urchin identification help

[Synthgp]

Hi all -

I was sold the following as a Halloween urchin, but get the feeling this is some sort of spiny urchin. Can anyone help me identify what type of urchin this is?

 

[Ron Reefman]

I think Halloween urchins have short spines (I'm 80% sure).

Yours looks more like a Rock Boring urchin. I snorkel in the Florida Keys and we have lots of Rock Boring urchins. They have fairly long spines and very red tests. They tend to find a hole in the rock (or make their own hole) and stay there. They don't move around much after they find a spot that they like and they tend to hide out under rocks rather than moving around. They do NOT cause issues with any other critters in an aquarium. I have 2 of them in my 40g AIO tank.

 

[Synthgp]

I think Halloween urchins have short spines (I'm 80% sure).

Yours looks more like a Rock Boring urchin. I snorkel in the Florida Keys and we have lots of Rock Boring urchins. They have fairly long spines and very red tests. They tend to find a hole in the rock (or make their own hole) and stay there. They don't move around much after they find a spot that they like and they tend to hide out under rocks rather than moving around. They do NOT cause issues with any other critters in an aquarium. I have 2 of them in my 40g AIO tank.

Ah - thanks for this. I agree. It looks like a rock boring urchin and generally finds a crevice I. The rocks and stays there during the day. It will come out and wander a bit and then go right back.

Just a bit annoyed as I was expecting a Halloween urchin and received this instead.

 

[Ron Reefman]

Ah - thanks for this. I agree. It looks like a rock boring urchin and generally finds a crevice I. The rocks and stays there during the day. It will come out and wander a bit and then go right back.

Just a bit annoyed as I was expecting a Halloween urchin and received this instead.

Don't be too upset, it's a good urchin. And unlike most other urchins, it's unlikely to pick up anything in the tank and use it as camouflage.

 

[ISpeakForTheSeas]

I'm a bit late here, but I would guess the Rock-boring Urchin, Echinometra lucunter - it's an herbivore.
Edit: For some decent pics to compare with (including some showing the reddish test with the paler gray spines):

STRI Research Portal - Echinometra lucunter