Waccamaw Gastropods II

[ClearLake]

I have been working through a bag of matrix that I received from @sixgill pete from the Waccamaw Formation (Pleistocene) of North Carolina.  Earlier I showed a couple of interesting bryozoans that I picked from the matrix (Waccamaw Bryozoan) and the first group of gastropods (Waccamaw Gastropods I).  From the 1 quart bag of matrix, I pulled out over 60 different species of gastropods and am up to about 45 species of bivalves!  This post represents the second group of gastropods that I have some identification questions about.  Again, these are all very small, most are only a few mm's.  I appreciate any input, thanks!!

 

1) The first one up may be the toughest, just because they are incomplete.  I have tentatively called them Cerithiopsis bicolor based on Gardners 1948 work and Campbells 1993 publication on similar aged material from Virginia.  As usual, I have tried to corroborate these ID's with other sources and tried to use the most up to date nomenclature based on what I find in WORMS, Fossilworks or The Neogene Atlas of Ancient Life websites.

 

2) Next is a really nice looking, but very small gastropod that I think may be Teinostoma carinatum based on Gardner, but T. lenticlare in Campbell also looks pretty similar.  Of course, neither may be right!!  This is one of three different species within the small Tornidae family that I found.

 

3) This one is also a very nice looking specimen but within several references I could not find a very good match.  The best I could do was a species of Vexillum based on the general shape, ornamentation and columnar folds but the ones figured in both Ward and Blackwelder (1987) and Dall (1890) had differences from mine.

 

 

4) This pair may not even be the same thing as you can see there are slight differences in the ornamentation, but I have about a half dozen and they seem to al least fall into a pretty similar group.  I have called these Chrysallida beaufortensis but am not at all confident in this especially since they my just be very young versions of something else.

 

 

5) This group is just part of well over a dozen that I found but can't put a good handle on.  Perhaps some species of Pyrgiscus (which may now be Turbonilla)?  Lea (1843) had a P. daedaleum which looked similar, but I was unable to find any reference to that species since that time.

 

6) And lastly, is a nice glossy but a bit chewed on specimen that I believe is a species of Turbonilla.  T. delta from Campbell (1993) has a description that sounds pretty similar but the illustration in my pdf is poor so I'm not certain.  

 

 

OK, that is all.  Again I appreciate anyone taking a look and if you have any ideas, I'm all ears!  Maybe @MikeR or @Coco will have some more excellent insights this time around.  Thanks again

 

Mike

 

 

[Coco]

Hi,

 

I can only tell you that I recognize the number 2 that I find in my lower Pliocene, as well as that of the last photo. On this one it seems to me that there are variations in the same species. I find almost smooth ones, others a little more striated. Maybe it’s wear and tear, but I see these differences on shells that come from the same place, which are in the same cubic metre of sediment.

My big problem is that I don’t know how to identify my shells, but I am very interested in the subjects that speak of them. Precisely this allows me to progress step by step by discovering things.

@MikeR will tell you a lot better than I will.

 

Coco

[ClearLake]

On 12/11/2020 at 1:43 PM, Coco said:

On this one it seems to me that there are variations in the same species. I find almost smooth ones, others a little more striated

Yes, that was also one of my observations, I had some that looked very similar to this except without the costae on them.