Hi Ranjeev!

It is very interesting your question,.. Ithink there is not papers about it.

I´m always be curious about that.

Gymnophallids (located between the valve and the mantle) may cause encapsulation with calcareous alteration (case of Gynophalloides nacellae in Nacella spp.), pits in Venus antiqua, igloos in several bivalve species, pearls in mytilids and go on. But nothing is known abbout the machanism and I have no idea how to study it Do you have any? I have followed experimental infestation aboy¡t 3 months in aquaria...

Best wishes,

Florencia

Thanks very much for your response Dr. Cremonte. I always thought that a live study and periodic analysis at different stages of the life cycle was the way to go. I am also guessing a study on the morphological and biochemical attributes of the parasite may also give us a clue on possible mechanisms. But since these interactions and responses may vary between species, there would be a lot of variables to control. I actually look at fossils with such traces.

Thank you

Best,

Ranjeev

Yes, you're right.

Both, morphological but mainly biochemical mechanism would be involved. The stage that we are talking is always the metacercaria (I´m sending you a paper whre we following the infestation from cercaria that enter the clam to an infective metacercaria, and the way they resulted encapsulated).

The metacercaria of this family (Gymnophallidae) has a large evolutionary history with their bivalve hosts. They do not encyst (as do the most of the metacercarias of other families) but are encapsulated by the bivalve mantle sectertions, that they modulae (in some way) to avoid die. Besides, they feed from the mantle secretion growing and maturing.

I think, that the principal actor in the modulation is not the bivalve species but the parasire species. Please, read the another paper I´m sending you, (Ituarte et al. 2001) where is demostrated that the same parasite causes teh same response (igloo) in very different bivalve species.

All of this I´m wrintting you is not published. I have the idea of do it...!

Good luck, Florencia

Thank you for your reply and thanks very much for the papers., Dr Cremonte! I am very new to the field of molluscan paleopathology, but I am gaining a lot of experience from discussions like this. I think this is a very important field of study cos many countries/ coastal communities rely directly on shell fisheries. Additionally, bivalves being ecosystem engineers/keystone species, at least locally, its important to see what are the underlying factors involved in trematode infestation.

Thank you

Best,

Ranjeev

Dear Ranjeev, I'm sending some articles related to your query.

Best wishes, Cristi´´an

Thanks very much Dr. Ituarte. Its fascinating how this little parasite can create such diverse trace morphologies on clams.