is this a clam cast???

[Tidgy's Dad]

5 minutes ago, ynot said:

@Tidgy's Dad, @RJB, @Shellseeker, @maxfossil,  

(Will not let Me tag anymore members here?)

(Please tag any shell, crustacean or brachiopod collectors You can think of for this survey, thanks.)

 

Should We refer to brachiopods and ostracods as bivalves?

No.

It becomes too confusing if we do so. 

Bivalves are the molluscan class Bivalvia. 

We can refer to brachiopods, ostracods and other two valved organisms as bivalved, but not bivalves, IMHO. 

[Max-fossils]

58 minutes ago, ynot said:

@Tidgy's Dad, @RJB, @Shellseeker, @maxfossil,  

(Will not let Me tag anymore members here?)

(Please tag any shell, crustacean or brachiopod collectors You can think of for this survey, thanks.)

 

Should We refer to brachiopods and ostracods as bivalves?

I agree with Tim and Adam here.

The term 'Bivalve' refers to any and all molluscs from the class Bivalvia. This class has had many old (and no longer accepted) names, 'Pelecypod' being one of them, along with 'Lamellibranchiata'. Those terms have been abandoned scientifically, and it is strongly recommended that we stick to 'Bivalve' now (it's also the easiest name to understand and remember  ). 

The term 'clam' is actually very imprecise, as on its own it can be used for a very wide range of different bivalves from different subclasses (however, if it is grouped with another word, usually an adjective, then it becomes an acceptable common name: eg 'Balthic clam' is a good common name for Macoma balthica). Although many bivalves can be called "clams", quite a few cannot: would you call an oyster, or a mussel, or a scallop, a 'clam'? I wouldn't!

 

Brachiopods and ostracods, although also having two valves, and sometimes looking very similar, are unrelated to bivalves, and shouldn't bear that name. It would cause more confusion to anything else. It would be like giving the name "Dinosaur" to a coral! The bivalves are already confusing enough on their own, and you definitely don't want to add more mess to the whole thing...  

 

 

By the way, Tony, I don't know if you were trying to tag me, but if it was me then don't forget the capital M, the hyphen, and the s at the end  

[Max-fossils]

19 hours ago, Peat Burns said:

He may have meant Lima (Plagiostoma)

Ah ok. That would make sense. Thanks for clarifying  

 

11 hours ago, Herb said:

what I actually meant was something like a Cyprimeria sp or even a Tapes sp  steinkern

Those two I don't understand why though... Lima and Cyprimeria or Tapes are not closely related? 

[Plax]

I didn't know pelecypod was abandoned scientifically. I had to read the wikipedia definition to find that was so. Have of course seen the term "bivalvia" in use. A lot of other scientific literature on the web and on paper uses the term pelecypod for bivalved mollusks. I agree that bivalve , as a noun, should only be used for pelecypods. I also think that we get hung up on technical specifics when general terms, especially for newbies, are more appropriate. Not saying a misstatement shouldn't be corrected of course.

https://www.uky.edu/KGS/fossils/fossil-pelecypoda.php

[FranzBernhard]

3 hours ago, ynot said:

Should We refer to brachiopods and ostracods as bivalves?

No, but I can understand the usage: The term "Bivalve" is obviously used for various double-shelled animal groups. But this is - should be - strictly informational usage (slang) - or better abandoned completely.

WoRMS sets it straight:

Franz Bernhard

[Rockwood]

Isn't there a project working on a whole different set of names for purely scientific use. It's terms carrying so much information that they are not meant to be remembered but stored as data.

[ynot]

2 hours ago, Max-fossils said:

By the way, Tony, I don't know if you were trying to tag me, but if it was me then don't forget the capital M, the hyphen, and the s at the end  

 My bad.

 

Yeah, I was looking to tag You.

[Herb]

4 hours ago, Max-fossils said:

Ah ok. That would make sense. Thanks for clarifying  

 

Those two I don't understand why though... Lima and Cyprimeria or Tapes are not closely related? 

I included those only as examples of steinkerns shaped like the one she posted, not as an ID.

[Herb]

4 hours ago, Max-fossils said:

I agree with Tim and Adam here.

The term 'Bivalve' refers to any and all molluscs from the class Bivalvia. This class has had many old (and no longer accepted) names, 'Pelecypod' being one of them, along with 'Lamellibranchiata'. Those terms have been abandoned scientifically, and it is strongly recommended that we stick to 'Bivalve' now (it's also the easiest name to understand and remember  ). 

The term 'clam' is actually very imprecise, as on its own it can be used for a very wide range of different bivalves from different subclasses (however, if it is grouped with another word, usually an adjective, then it becomes an acceptable common name: eg 'Balthic clam' is a good common name for Macoma balthica). Although many bivalves can be called "clams", quite a few cannot: would you call an oyster, or a mussel, or a scallop, a 'clam'? I wouldn't!

 

Brachiopods and ostracods, although also having two valves, and sometimes looking very similar, are unrelated to bivalves, and shouldn't bear that name. It would cause more confusion to anything else. It would be like giving the name "Dinosaur" to a coral! The bivalves are already confusing enough on their own, and you definitely don't want to add more mess to the whole thing...  

 

 

By the way, Tony, I don't know if you were trying to tag me, but if it was me then don't forget the capital M, the hyphen, and the s at the end  

I try to use nomenclature to fit the wording of the post.