Our Final write up on Permian Fort Apache - Gastropods

[Arizona Chris]

 Hi All,

 

This marks the final chapter of this years exploration of the Permian Fort Apache Limestone micro fauna found east of Payson, Arizona.  This entailed sorting throgh thousands and thousands of tiny gastropods under the microscope, and catagorizing them into 22 types.  We then set out to identify as many as possible.  Here is a part of the photo tour, the rest can be found on our website!

 

Gastropods / Monoplacophorans from the Permian Fort Apache Limestone East of Payson

 

By far, the largest project in the Fort Apache Limestone series! We found more tiny gastropods than any other type of fossils in the acid fines. Literally thousands and thousands of pinhead sized gastropods and monoplacophorans were found, and after months of picking through the residues, we had several teaspoons of the microscopic fossils. The sorting process took weeks and we decided to sort them according to morphological type. This yielded 22 different varieties, some of which may have been duplicates that were preserved different or incompletely. Fortunately for us, Winters in his huge GSA 89 monograph identified scores of gastropods making many of the identifications possible for us. We also found several types which he did not show or mention.

The conclusions that can be drawn from our gastropods is still clear - a very muddy bottom which preserved huge numbers of juveniles either because of inclement conditions for their survival or a high mortality rate. The preservation ranges from very poor to superb. Many of the smallest fossils show amazing details in their outer shells and large numbers of ornamented types were uncovered. The most common type was the small squat cones, ten times more common than any other type. They were also the very smallest to be found as well.

 

Bellerophon sp. - Monoplacophoran

There is considerable controversy as to where Bellerophon resides in the mollusk group. Latest papers seem to indicate that it is about half way from the limpet shaped basal primitive monoplacophorans and the accepted standard gastropod. No one has ever found fossils of their soft anatomy, and until this occurs, they will remain an enigma.

 

 

Ribbed Cones (Paleostylus giganticus)

 

 

Honey Buns (Apachella prodontia)

10x view of a nice collection of bun shaped gastropods with a unique proto conch region.

 

Ornamented Rimmed Buns (Worthenia arizonensis)

Fantastic ornamentation on these!

 

 

Ribbed Bellerophon shaped Gastropods (Knighties modestus)

These look very much like a Bellerophon but they do not have the same fine features defining that group. They are much smaller too, pin head sized.

 

 than

 

Many Many more can be seen on our web site, Thanks for looking!

 

our web site page:

http://www.schursastrophotography.com/paleo/Fortapache-15.html

 

 

[ynot]

That is a lot of "escargot" You found.

You are doing really well with the pictures too!

Thanks for sharing Your work here.

[Miocene_Mason]

It been interesting learning about this formation, thanks for posting! 

[Arizona Chris]

Thanks - its been quite a learning experience making 12 layer focus stacks of so many gastropods.