Rucks Pit Gastropods 1

[Koinonia]

Back in 2003 I and my daughters visited Rucks Pit with the Georgia Mineral Society.  They gathered everything, more than I realized. Now years later I am actually trying to identify everything we collected.  Dr. Ed Petuch was there, and I bought one of his books which I hoped would have been more helpful.  I see it does extensively split the various genus and unfortunately the plates are of poor quality.  I have to admit I am very frustrated with the contradictions in scholarly literature that one can find.  I principally used the University of Florida website and WoRMS, but in the end, I am just guessing.  I thought for awhile that WoRMS was closer to the official organization obtaining consensus, but I am questioning myself on everything.  I found that I have a lot of shells and will have to break this into at least 3 postings eventually.  I can retake pictures if needed.  You can correct me as needed.   I have already spent days on this.  All of the formations in the tags were mentioned in the old handouts I had.  I would like to hear the proper time periods for Rucks Pit.

 

1 Oliva Sayana (not even on U of F site)

 

 

2 Neoterebre Dislocata (accepted Genus on WoRMS)

 

 

3. Turritella Conspersa (With so many species many without pictures I could easily come up with a number of possibilities.  It is not on U of F so is likely an error.)

 

 

 

4. Turritella Wagneriana (Not on WoRMS, but it seems to be the answer on the Forum.  Staring at these initially, I thought the two at the far right were a different species.)

 

 

 

5. Cerithium Muscarum

 

 

 

6. Phrontis Vibex

 

 

 

7. Cancellaria Cannoni (Not on WoRMS but with the genus having 265 children and many with contemporary pictures, it is just another guess by what I see on the U of F site.)

 

 

 

8. Fasciolaria Lindae (Same comment as immediately above.)

 

 

 

9 Toroliva Gladeansis (The genus was not on WoRMS and the Neogene period seems a little early.  There were lot of these inside other shells.)

 

 

 

10. Planorbella Duryi  (WoRMS rejected the genus.)

 

 

 

11. Neverita Duplicata

 

 

 

12. Prunum Apicinum (Put in the broken shell to get a better view.)

 

 

 

13. Septastrea Marylandica (Not on WoRMS again.  The bottom right could be S. Cressa.  The top right I threw in here but could just be unidentifiable fragments.)

 

 

 

14. Vermicularia Weberi (top), Vermicularia Spirata (left), Serpularbis Granifera (Thylacades Granifera per WoRMS.  When organizing I found them at different times so the IDs were determined at different times.  Seems impossible to identify characteristics to me.)

 

 

 

15. Triplufusus Giganteus (Very damaged and I am afraid to try going any further with cleaning out the inside.  There is still a good amount of material in the top section. I think I had a different ID back in 2003.)

 

 

 

16. Gyroscala Rupica

 

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17. Conasprella Jaspidea (bottom 3), Conus Duerri (middle top row and not on WoRMS), Conasprella Onisca (for the other 2, but maybe I should put Jaspidea as well.  Not on WoRMS.)

 

 

 

18. Terebraspira Maryae (The two bigger ones.  The genus is not on WoRMS.), Turbinella 

Regina (the smaller middle one on the first screen.  The species is not on WoRMS.)

 

 

 

 

19. Chicoreus Xestos (Species not on either site, but I went with what I could see on the forum.)

 

 

 

20. Ficus Ficus (It was on WoRMS so I went with it. To me the Ficus all look very much alike),  Turbinella Chipolana (On the right is not on WoRMS and looks like wrong era on U of F but the picture struck me), Gemophos Tridentotus (Bottom one.  I went with the Forum despite not being on WoRMS.)

 

 

 

Done for now. I appreciate any guidance.

[Fossildude19]

@MikeR

[minnbuckeye]

I believe Ruck's Pit is early Pleistocene. Nice collection. Would love to see your calcite fossils from there! 

[Koinonia]

Thank-you.  The original notice I received only mentioned the Anastaisa Formation which apparently is only about 110k at its oldest, thus considered to be in the very Late Pleistocene era.  The notice stated that this was where the coquina matrix containing the marine fossils with calcite were located.  In a later report of a second trip, it states that the coquina matrix is in the Nashua Formation considered Early Pleistocene.  A rather significant contradiction.  I was trying to gauge when examining these shells whether I should to limit the identification to Late Pleistocene only considering none had calcite deposits.  I was guessing that those calcified would be older.

 

Yes, I have calcite fossils, although I cannot say I have anything extraordinary.  I will have to look through them again.  While I could identify the fragments coming from Whelks or Clams, I was struggling to identify at any level the one I have attached below.  I was going to post the front and back at a later date, but what do you think it was?  

40.

 

[MikeR]

Greetings from Dallas, GA.  It looks as if you have fallen into the bane of the fossil shell collector; taxonomic lumping vs. splitting.  It is something I have commented on before in multiple posts, however I plan to do this once more with more detail, one day, probably after I retire in a few years.

 

Petuch is the ultimate splitter, rarely recognizing any variation between individual populations.  He publishes books on fossil mollusks which are very popular with amateurs, but discounted by professionals.  He can't be ignored totally as he does have valid species, but it takes a fair amount of time to work through the noise.  I have tried to do some of that through my Gallery Album LINK, however it is incomplete and needs some revisions which I haven't had time to do.  My main reference is the FLMNH db and I do have success with it only because I have been working with Cenozoic mollusca for almost 40 years consulting with Roger Portell at the FLMNH and Buck Ward formerly with the VMNH.

 

I never visited Rucks Pit, however according to the literature and specimens that I acquired in trades, the Mercenaria layer with the calcitic interiors are from the Middle Pleistocene Bermont Formation which overlies the Upper Pliocene Pinecrest Member of Tamiami Formation from which your shells derive.  I don't do many identifications any longer because of the time it takes, however for a neighbor I will make an exception.  As follows:

 

1. Oliva carolinensis an ancestor of O. sayana.
2. Correct
3. Turritella perexilis
4. The two on the far right are Turritella wagneriana, but the others are more interesting.  Last year a revision of Plio-Pleistocene Turritellidae was published in Bulletins of American Paleontology No. 402.  The others in your picture resemble Turritella pontoni, a large species reaching 3-4 inches.  Yours are smaller, more on the 1 inch size, but the width/height ratio appears correct.
5. Correct
6. The specimens with the thickened parietal shield are Phrontis vibex, those which don't, look like Nassarius floridensis.
7. The shell second from the left appears to be Massyla rapella while the others are Muricids, possibly Trossulasalpinx subsidus, but I would need to see one up close to be certain.  
8. Perhaps Cintura apicina.
9. Correct
10. Correct
11. Correct
12. Two species.  The small ones with 4 columnar folds Prunum pardalis, the large one with 5 folds, Prunum precursor.
13. Correct
14. Worm shells can difficult to ID, but you are probably correct on all three. 
15. Correct
16. G. rupicolum
17. The 3 on the bottom are Conasprella oniscus.  The two on the upper right Conus anabathrum.  The upper left I would need to see the other side, probably one of the other two.
18. The two larger, I call Pliculofusus acuta, but the entire subfamily needs to be revised with similar species in the Carolinas.  The smaller is immature T. regina.
19. I would call Chicoreus floridanus.
20. The fig shell found along present day Florida has been misidentified many times in various publications, however it would be Ficus papyratia.  The Pliocene form is Ficus jacksonensis, but I would need a closeup of the shell sculpture to be sure.  Another immature T. regina and Vokesinotus perrugatus.

 

I would be interested in trading for good examples of what I think are Turritella pontoni and Trossulasalpinx subsidus to study.  I have so much Plio-Pleistocene shells coming out of my ears that I can give you great examples of almost any species you like.  If interested, PM me.

 

Mike

 

[Koinonia]

Thank-you for your response.  I really appreciate it.  I admittedly have little background and spent the time looking at the plates on the websites.  I was using the FLMNH db when I mentioned the U of Florida if I was not clear.  Of course, now I have work mostly examining the Phrontis, Prunum, and Cones that I did not include in the post.  

 

Interesting the Bermont formation was not mentioned on the trips.  I am attaching a diagram from the second trip's report I found.

 

ft-drum_section1a.pdf  

[Plantguy]

Cool finds and thread! I always learn more about some of this stuff thru others finds and question. 

I'm glad Mike was able to confirm/assign ID's. I've never been down there ( thought alot of your material looked like Tamiami material that we find up here in Sarasota County pits but I'm not an expert like Mike is) but here's the info I had from the SEG guidebook to Ruck's Pit--maybe you have this already. 

 

From that SEG field trip guide:

RUCKS’ PIT Okeechobee County, Florida, USA Compiled by:  Gary L. Maddox, Dr. Thomas M. Scott, and Guy H. Means

SOUTHEASTERN GEOLOGICAL SOCIETY GUIDEBOOK NUMBER 45

Prepared for the Fall Field Trip of the Southeastern Geological Society December 3, 2005

Published by the  Southeastern Geological Society P.O. Box 1634 Tallahassee, FL 32302 

 

From page 7:

"STRATIGRAPHY  The sediments exposed in the Rucks’ Pit were deposited in the late Pliocene and Pleistocene under shallow water near shore conditions. Subsequent sea level fluctuations allowed for the dissolution of some shell material and the cementation of the beach and near shore shelly sands creating the rock mined from the Rucks’ Pit. Petuch, in an undated volume published by pit owner Edwin Rucks, Jr., applied a stratigraphic sequence to the exposure in the Rucks’ Pit which included a new group and new members which need to be defined following the North American Stratigraphic Code (2005). This includes complete descriptions of the new units, requiring mapping the areal distribution and thickness variability of the group, formation or member. Until that time, the names should not be used in any way other than an informal manner.

 

 

Figure 2 depicts the generalized lithologies exposed in the Rucks’ Pit. Thicknesses of the units are quite variable over the area encompassed by the old pit and the active operation. Quite a bit of lithologic variation occurs within these units, particularly in the lithified beds. 

 

The basal unit exposed in the pit at lowest water and often seen in spoil piles is part of the Tamiami Formation, a highly variable, complex unit widespread in southern Florida. A number of fossil mollusks attributed to the Tamiami Formation have been identified by Petuch from the basal sand unit. Lithologically, the unit consists of fossiliferous, fine quartz sand with variable percentages of silt, clay and carbonate. This unit is generally not well exposed. Overlying the basal unit are the variably lithified beds that appear to be transitional between the Caloosahatchee “beds” to the south and the Nashua Formation to the north. This unit varies from a densely packed, imbricated Mercenaria valve bed to an occasional thin clay stringer. Much of the unit is composed of variably calcium carbonate cemented, shell bearing sand. Some beds can be classified as a very sandy limestone. Petuch has recognized fossil mollusks attributed to both the Nashua and Caloosahatchee units. The Mercenaria within this unit occur as paired valves in life position, paired valves not in life position, separate valves with an imbricated orientation indicating significant current energy, and separate valves exhibiting no particular orientation. The sediments above the variably lithified Nashua-Caloosahatchee unit are composed of quartz sand with varying percentages of organic matter and an abundance of fossil mollusks. This unit has been referred to as the Fort Thompson unit. Undifferentiated surficial sands overlie the Fort Thompson shelly sediments. "

 

Regards, Chris