?

[wicked_NaCl_h2o]

Is a sand dollar and a sea biscuit the same thing?

 

[greenbean36191]

They're both common names for several species of modified sea urchins. Usually sea biscuits are the thicker species without the holes through the test while sand dollars are thinner, have sharper edges and usually holes or lunules through the body.

 

[charlesr1958]

Heres a photo of a "sea biscuit" that are commonly found in my DSB, not that I put them there on purpose, but I guess they come in at tiny juveniles unnoticed when I add or swap out live sand.

Chuck's Addiction

Chuck

 

[wicked_NaCl_h2o]

Does this look like a sea biscuit?

 

[wicked_NaCl_h2o]

<a href=showthread.php?s=&postid=12683395#post12683395 target=_blank>Originally posted</a> by charlesr1958
Heres a photo of a "sea biscuit" that are commonly found in my DSB, not that I put them there on purpose, but I guess they come in at tiny juveniles unnoticed when I add or swap out live sand.

Chuck's Addiction

Chuck

yours looks more like the heart urchin

 

[wicked_NaCl_h2o]

Does anyone else think so too or am I wrong?

 

[mollymonticello]

I think they're similar or the same.

 

[charlesr1958]

Not sure by what is meant as a "heart" urchin as common names can be and are often quite confusing. What ever species I do have, never comes out of the DSB into the open and behaves very "sand dollar" like.

Chuck

 

[mollymonticello]

Sorry for the lazy reply there. I didn't realize it was you, Chuck. I should look at peoples usernames more often. Heart urchins are probably Eurypatagus ovalis and Sea Biscuits are Eupatagus ocalanus. So they are in the same genus. Actually, I would consider a Heart Urchin a type of Sea Biscuit.

Chuck, your website is awesome.

 

[pagojoe]

Right. Another example of trying to nail something down by common name. If it's in the same genus as something else, it's obviously closely related. The thing in Charles' pic is what I call a sea biscuit. It looks a lot different when only the test is visible. As greenbean mentioned, the name is applied to several "puffy" urchins/sand dollars...which is all meaningless anyway, thus the agreement to use scientific names if the purpose is to refer to a single species. It can also prevent discussions or arguments about such things as what a REAL "sea biscuit" looks like.

Cheers,



Don

 

[pagojoe]

I should have read all the posts. Yes, Christina, yours is also one of the urchins called a "sea biscuit."

Cheers,



Don

 

[charlesr1958]

Thanks All, I think that clears it up...lol One man's sea biscuit is anothers sand bun...lol

By chance, does anyone have a good online reference for such critters?

Chuck