Jump to content
Tiesta

Gastropods Of The Twin Cities

Recommended Posts

Tiesta

I'm going to provide some information about the gastropods which interesting enough comes in a huge diversity of different species. You are welcome to add informations or correct any misid or name changes thou they obvious have invertebrate fossils very low on their list of classification....

Edited by Tiesta

Share this post


Link to post
Share on other sites
Tiesta

First up are Hormotoma gracilis. To me it's common in Decorah formation usually massed together. Didn't see any in platteville formation so far. Tiny turritella like snails 1.5 mm in length. Often easy to overlook.

Share this post


Link to post
Share on other sites
Tiesta

Next up are Liospira obtuse. When I first found it it looked like worn Brachipod or trilobite part peeking out then cleaning reveals that's it is a snail. To me they're uncommon in platteville as cast mold hadn't found in decorah and tend to be massed together. Very distinct shape, kinda like a modern sundial snail but rounded edges. Vary in size, one specimen being one and half inch in diameter for the biggest I had found thou little ones about a millimeter in diameter had been found.

Share this post


Link to post
Share on other sites
Tiesta

Next up are Phragmolites fimbriatus. Often confused with Cyrolites retrorsus. I had only found it in platteville so far. Uncommon to me so far massed together. This is to me one of the top 5 beautiful gastropods fossil from the Twin Cities. It occurs as cast mold, generally one inch in diameter. Negative mold have zigzag lines repeated all along the whorl probability due to its unique structures near its mouth which flares out and is supported by rods like structures on the outside.

Share this post


Link to post
Share on other sites
Raggedy Man

I do not believe that any member of the forum logs on with the intention to troll, express a rude attitude or offer vague uneducated comments. We're here to learn and share our collective passion with each other. The scientific method is embraced by all, but on occasion some allow their personal ideologies (religious or other) to eclipse the truth. However, they're kind people and they keep this aspect to themselves.

I think that any issue that does come up will be swiftly dealt with long before it's noticed. I also think that your comment was premature as that type of behavior is not tolerated within TFF community.

If you experience any problems with any member, I'd hope that you'd bring it to the attention of the moderators.

Best regards,

Paul

Share this post


Link to post
Share on other sites
Tiesta

Ok I will change that sentence but just let you know I'm sensitive to any negative emotions and I found a few years ago that ignore is the best solution for me, the other person, and the community.

Share this post


Link to post
Share on other sites
fossilized6s

I agree with Paul. Also, i don't want to undermine what you are trying to do here, it sounds good so far. But myself and others are visual learners, and detailed in focus pictures speak a thousand words.

Share this post


Link to post
Share on other sites
Auspex

Ok I will change that sentence but just let you know I'm sensitive to any negative emotions and I found a few years ago that ignore is the best solution for me, the other person, and the community.

I do not expect any trouble from our community, but if something escapes my attention, just let me know :)

Share this post


Link to post
Share on other sites
squali

I appreciate your efforts but it would be beneficial to all if you could provide some pictures of the Gastropoda you are referencing.

Share this post


Link to post
Share on other sites
Tiesta

Be patient with pictures it's going to take a while to figure things out. ipad is just too blurry and primitive and I need to get my desktop computer fixed.

Share this post


Link to post
Share on other sites
Auspex

We have all the time in the world; thank you for your efforts :)

Share this post


Link to post
Share on other sites
Tiesta

Sinuites pervolutus and concinna are very common in decorah. They are simple smooth snails that look like some forms of pond snails. They are often difficult to tell from pebbles left by glacial till when eroded out of rocks and when present in rocks often look like smooth pebbles rising out of the rock. Pervolutus are more ball like in shape and in intact specimens have a mouth that flares out hard so it have more like half a circle in shape. Concinna have narrow mouth and a shape similar to some rams horn snails. When at rest they often lies on their side.

Share this post


Link to post
Share on other sites
Tiesta

Ok I'm back after being busy so much gardening, collecting more fossils, organize and name modern day fla shells, etc. During winter, fed up by the poor lack of information I decided to use common names as they can possible tell species or even subspecies apart. Either I will be the only one using common names or it will catches on. Takes Hormotoma gracilis. I came up with a common name connected to what I thought I saw when I first found it. Fish corpolite snail as when I first saw it in limestone it bears a striking resemble to certain fossils of fish corpolite.

Share this post


Link to post
Share on other sites
Tiesta

post-2767-0-55780000-1459460086_thumb.jpgpost-2767-0-00730800-1459460144_thumb.jpg

Liaospira obtusa

Edited by Tiesta

Share this post


Link to post
Share on other sites
Tiesta

post-2767-0-86702100-1459460951_thumb.jpgpost-2767-0-51739000-1459460978_thumb.jpg

The most complete one I could find as it is very difficult to cut platteville right. Phragmolites fimbriatus and a piece of its cast showing unique textures

Share this post


Link to post
Share on other sites
Tiesta

With the genus Sinuites I found out there's more than 10 species and it's hard to Id since their lips are often fragile and broke easily. For now I just have three common names two are very abaduant and one rarer. Hammerhead Sinuites I gave them that name because their lips abruptly widen often wider than their entire shell. Size vary but usually smaller than the next species which are either the most abaduant or broken in different species. Giant Sinuites because they can be the largest of the Sinuites species at nearly one inch. They are also the most ordinary Sinuites as their lips ain't fancy just extends out a bit and are rounded. The last one beaked Sinuites is from one fossil. It's spiral are narrow and either that's it ridicious stretched out beak or a Brachipod just happen to align almost exact with its lips.

Share this post


Link to post
Share on other sites
Tiesta

With Ophiletina angularis I only found one so far. Look like galena formation. Very flat spiral, the most flattest fossil shell I have seen so far.

Share this post


Link to post
Share on other sites
Tiesta

Hormotoma trentonense only found one so far. Wider body whorls and a bit of pointed lips. And this is only missing it's top spires so good sized one from decorah. Mine is one and a half inch.

Share this post


Link to post
Share on other sites
Tiesta

post-2767-0-43097800-1459463460_thumb.jpg

The top one is Hormotoma Trenton ensemble the two little ones below it is unknown species.

Share this post


Link to post
Share on other sites
Tiesta

post-2767-0-79150600-1459463909_thumb.jpg

This is the last one from the first box. I'm going to do a second box another day maybe next week.

Share this post


Link to post
Share on other sites
Tiesta

Look like it will be colder for part of this week so wait to rake leaves again. I obviously got tired and forgot to describe the last one lol. Cyrolites retrorsus. Also another ammonite look alike gastropod. I don't know if the bigger one is a different species yet. They are tiny and kind of easy to overlook. I found it both at shadow falls and lilydale. One even have a partial covering of what look like bryzoan species. Very unique, only Phragmolites fimbriatus can be mistook for it but I have only found Cyrolites retrorsus in decorah and Phragmolites in miffin so far. Cyrolites retrorsus is far smaller with beautiful pronounced ridges that spiral around the tight coiled shell that have no flare of the lips. I rate it as uncommon to common.

Edited by Tiesta

Share this post


Link to post
Share on other sites
Tiesta

The next box contains one species of Fusipira a few unidentied odd and ends and what I think includes members of the superfamily Trochoidea and lookalikes. It will have to be certified by a expert and it's tough looking through the mazes of families, genus. First up are Fusispira nobilis. This one looks similar to large Hormotoma species but is more tighter spiral and kind of weird coils to it. I found two in galena formation, and they apparently are fragile you can see all the glue I use to fit parts together sigh. The weird coils look like if you take a dough and cut it in a rectangle pattern with flat sides then try to coil it up, with the next spiral thicker than the next.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Recently Browsing   0 members

    No registered users viewing this page.

×