My Purple Linkia

[Pufferpunk]

Surprisingly, he didn't guess it was the madreporite. I was still under the impression when I wrote him yesterday, that it was a deeply burrowed Thyca crystallina. He said they could burrow that deeply but not much to do other than surgery. Best if left alone though. I wrote another letter about the madreporite being open like that (almost positive that's what it is, after scouring countless pics). Waiting for a response. I wish the star would come out, so I can look again.

 

[AuroraDave]

Have you read this?

http://www.advancedaquarist.com/issues/may2002/toonen.htm

Near the end:
Another consideration is that these stars are particularly prone to parasitic infections of the small snails (Thyca crystallina), and in some regions as many as 1/4 of the Linckia are infected with these pests . You should check for these snails clinging to or boring into the underside of the arms before you pay for the star. Females of these parasitic snails have a proboscis (elongated mouth) that penetrates the skin of the sea star and sucks the hemolymph (the echinoderm equivalent of blood) almost like a small, shelled mosquito. Unlike a mosquito, however, the adult snail actually burrows into and becomes permanently fused to the sea star, and should never be picked off! Because it is physically attached to the sea star, removing the snail will almost certainly result in more damage than leaving the snail attached. Besides, these parasitic snails turn out to be a relatively minor problem. Other than a slight alteration in some of the skeletal elements around the proboscis, the main effect of these snails on the star appears to be the loss of tube feet under the snail’s shell (which probably has no effect on the health of a star in the aquarium over the long-term).

Although research suggests that these parasitic snails cause little ultimate harm to their hosts , their presence is an additional stress that the stars can do without when being moved to an aquarium, and their presence provides a potential vector for infection. So, if you have your choice of several healthy stars, take one without any parasitic snails first; if you don’t have a choice, it probably won’t matter to the star in the long-run.

 

[PSam]

So my initial thought may be correct on Thyca? The thing is that IS where the sieve plate is located, more or less. But as a couple of us have said, never seen one open like that. On the other hand, I've never seen Thyca burrow in the top center like that. so... PLEASE keep us posted. I'm very interested to hear what others say.

 

[Pufferpunk]

I tend to agree w/Psam, that it is not the parasite, only the madreporite. It is in the exact same place on my blue linkia. If the darn thing would only show it's "face" again, I could see if it's still open or not.

 

[hansnfrans]

Aurora Dave - Thanks for posting that excerpt. It's good to know that these snails aren't too terribly harmful to the starfish. One less thing that I have to be paranoid about in my aquarium

 

[Pufferpunk]

It's also nice to know what to inspect the stars for, although I got this one from someone's tank.