Pteria, Mollusk, Oyster, Pinctada… what am I talking about? The beautiful pearl making species... they are not oysters, per se, so what are they?!
I just wrote a post where I used all of these words referring to one species of mollusk and I fear that you have NO IDEA what I am talking about! I can’t blame you! So I am going to talk through why I use all these completely unrelated terms.
First, an oyster.
We all know what those are, right? Many have been gobbled up while standing around a piece of plyboard, elevated by sawhorses, while enjoying the musky thick heat of the South Carolina coast. Yum! (actually, truth be told.. I am not a huge fan of eating oysters even though I enjoyed quite a few oyster roasts with my friends in Beaufort!).
But, you know what I am talking about, we all know oysters.
If we take it on back to our species classification in school that starts with animals…the classification moves from Animalia (Kingdom) to Mollusca (Phylum). I love using the word mollusk (mollusca, mollusc) because it casts a wide net. Mollusks include all bivalve species but other species as well including sea snails (which can occasionally form a pearl) and octopus (no pearls there!). But, I do feel very all-inclusive when I say mollusk because both saltwater and freshwater species are in the phylum mollusk. Let's look at our Tennessee River mollusks that form our natural Tennessee River pearls:
The most common families are the Margaritiferidae and the Unionidae.
So, we have these mollusks. And we have these oysters. Why are they called oyster? Well, it is a variation on the order Ostreoida.
These oysters do not create our beautiful gem quality pearls. These are the oysters we eat! So, why do I refer to our pearl making gems as oysters. Well, it is easy to relate to! If you hear me say oyster you get a sense of what I am talking about, right?
But, let's get technical. What are the pearl bearing mollusks that we are breeding and harvesting pearls from. These are the Pinctada!
These species are P. mazatlanica, P. margaritifera, P. imbricata, P. maxima, etc.
In the Sea of Cortez we have the lovely Pteria genus creating the lovely Cortez pearls.
Species: P. sterna
So, they are not oysters although I might continuing calling them oysters, or mollusks, or bivalves ... but now you know what they truly are! Enjoy!