First Hunt of 2017 in Minnesota

[Bev]

We are having a highly unusual, but welcome, respite from winter here in Minnesota. Temps have been in the 40s and 50s for several days and the snow is slowly departing. Rain is even forecast  for tomorrow, but snow is predicted to return next weekend, so a fossil hunt sounded like a wonderful pursuit for a Sunday afternoon. The breezes were light, even balmy for February, green grass blades are starting to poke through and a flight of geese could be seen in the blue skies heading north - a sure sign of an early spring. I headed to one of my favorite hunting spots to see if it was melted off.

My very first find was this gorgeous Halysites Coral! These are rare in these parts and this one is the biggest I have ever seen, but it is caught in the rock. :-(

The location of this coral is very unusual as I have never found one at this level.

 

Since I couldn't get this one out with the two hammers I had, I proceeded to wander the upper shelf of the Stewartville member of the Galena formation in this area collecting Maclurites,  a lovely Fusispera sp., a broken trilo cephlon, and a warn cephalopod among other treasures.

 

Continued...

 

 

[Bev]

Here is my haul from that quarry. It was heavy carrying it in my backpack. I like to pick up pieces to give out to children.

 

Here is a near perfect internal mold of a Maclurites showing a bit of the original shell which is very unusual. Above it is a trilo ceph, broken but showing 450 myo shell also. For whatever reason, brachiopods are not found in this quarry.

Here is the Mac with an internal mold of a Fusispera sp. gastropod nicely preserved.

 

Continued...

 

 

[Bev]

And I found this that I believe is an Ordovician coral, perhaps Hexigornia (sp?) that is very worn. First time I have ever found a coral like this in this spot.

 

I decided to continue my hunting in another spot that I haven't been too in at least 3 years. Within a few minutes I found this broken trilo ceph in this not so dry, drywash.

 

 

 

I turned up the drywash wash and continued searching. This is also the Galena Formation but mostly in the Cummingsville member.

 

Note the trusty fossil dog lying on a rock filled with Fisherites.

 

Continued...

[Bev]

How many do you count? And when I picked up my backpack there was one under it!

 

Looking up the drywash.

And more Fisherites! There is a whole layer here that is really quite spectacular.

And more...

\

But as I got further up the wash, the snow became thicker and I was finding fewer fossils.

 

Continued...

 

[Bev]

In Minnesota, it is pretty special to see open water and green in February.

This was my haul from the wash besides some great photos of fossils I couldn't take home.

I started the day out in my jacket and ended up in just my sweater - what a wonderful day to fossil hunt in Minnesota!

[ynot]

Wow Bev!

Nice finds and wonderful trip!

Thanks for sharing.

Tony

 

PS Good to see You are getting out (and in February to boot)!!!

[Darktooth]

Thanks for the great report and pics!

[GeschWhat]

Fossil hunting in February! Too mucky with the snow melt here. Your fossil dog is adorable, Bev!

[FossilDAWG]

Fossil hunting is indeed unusual in February in Minnesota.  Glad you were able to get out.

 

The "chain coral" is almost certainly a Catenipora.  Halysites did not appear until the Silurian.  In Catenipora, all the corallites in a chain are the same size.  Halysites has tiny tubes inserted between the larger corallites.  You might also run into Manipora, which has parts of the colony in the chain coral growth form, and parts that are cereoid (corallites packed together in a mass, so individual corallites are hexagonal like Favosites).  Also the "chains" in Manipora are often double rows of corallites, instead of single rows as in Catenipora or Halysites.  Both Catenipora and Manipora are common in the Red River Formation in Manitoba, which correlates with the Galena, so either might show up in your area as well.

 

Don

[Archimedes]

wow nice day out collecting in the winter of Minnesota

[smt126]

Nice haul Bev. We had some nice warm weather here too, but unfortunately I have some puking little ones, and we weren't able to enjoy the nice weather as well. One of my twins who is not sick brought a big chunk of the fossils we dug up there by you to show and tell this week. He said everyone was really excited. You have some great lands to explore out there. Thank for adding all the pictures of the areas as well as the fossils

[aek]

Nice! I'm hoping to check out the SE Minnesota area soon.

[Wrangellian]

That's a nice plate covered in Fisherites, Bev, it's too bad it can't be taken out of there.

Suprising to see that your area looks a lot like our area this time of year - our show is pretty much gone but it wasn't too long ago that it looked like your photos, but of course this year is a La Nina. A couple years ago we had early spring from the beginning of Feb with flowers and all..

[Malcolmt]

Still looking to get out for the first time this year up here, almost went last weekend but rained constantly. Currently -16 with -6 for the weekend so looks like no fossiling again this weekend. But if Minnesota is good to go then we can't but much further behind.

[Bev]

On 2/20/2017 at 10:05 AM, FossilDAWG said:

Fossil hunting is indeed unusual in February in Minnesota.  Glad you were able to get out.

 

The "chain coral" is almost certainly a Catenipora.  Halysites did not appear until the Silurian.  In Catenipora, all the corallites in a chain are the same size.  Halysites has tiny tubes inserted between the larger corallites.  You might also run into Manipora, which has parts of the colony in the chain coral growth form, and parts that are cereoid (corallites packed together in a mass, so individual corallites are hexagonal like Favosites).  Also the "chains" in Manipora are often double rows of corallites, instead of single rows as in Catenipora or Halysites.  Both Catenipora and Manipora are common in the Red River Formation in Manitoba, which correlates with the Galena, so either might show up in your area as well.

 

Don

 

Sorry for being missing, very, very sick, but coming around finally.  :-)

 

 Hi Don, I don't mean to be a pain, but Halysites is indeed an Ordovician coral and I have collected 2 others in this location. This particular one may not be, but I haven't been able to collect it, just photograph it as it is stuck in the rock.  :-(

 

Please Note: Index of Fossils of North America, Shimer & Shrock 1944 page 113:

 

[Bev]

On 2/23/2017 at 2:33 AM, smt126 said:

Nice haul Bev. We had some nice warm weather here too, but unfortunately I have some puking little ones, and we weren't able to enjoy the nice weather as well. One of my twins who is not sick brought a big chunk of the fossils we dug up there by you to show and tell this week. He said everyone was really excited. You have some great lands to explore out there. Thank for adding all the pictures of the areas as well as the fossils

I've been horribly sick too! Just getting back on my feet. Neat that one of your boys took a fossil to school and the other kids liked it, especially when he can tell them the story about collecting it too! They sure broke rock!  LOL   :-D  All he has to say is that it is older than the dinosaurs and he should be good to go with the kids.  :-D

 

Thanks everyone for the nice comments. We had a blizzard right after, but it is melting off and predicted to be in the 50s this weekend. I'm hoping to get out again on Sunday, but we'll see how I'm recovering.  :-)

[Bev]

On 2/25/2017 at 0:42 PM, aek said:

Nice! I'm hoping to check out the SE Minnesota area soon.

 

First check out my blog. I do have 3 different fossil hunting maps in 2 counties that will make your trip a lot easier and I do fossil tours and hunts.  :-)

[FossilDAWG]

Hi Bev,

 

The name "Halysites gracilis" is an old name that was repeated uncritically in many field guides and geological papers that were not primarily concerned with coral taxonomy.  At one point in time the name was automatically used for all chain coral specimens from the Ordovician of the midwest and west.  At that time also, all "chain corals" were called "Halysites".  Subsequent study indicated that there was significant variation of structure with the chain corals, too much to be encompassed withing a single genus.  Today several genera of "chain corals" are recognized.  One major feature is the presence of minute mesocorallites between the larger autocorallites that make up the chain.  The autocorallites are the tubes you see with the naked eye, that are strung together to make up the chain.  The mesocorallites can only be seen by making thin sections and examining the specimen microscopically.  The old reference (1944) you cut/pasted from has the following definition for "Halysites gracilis":

"Differs from H. catenularia in having corallites almost quadrangular in section and apparently lacking an intervening minute tube."  I have underlined the important feature.  All Halysites, as that genus is currently defined, have an intervening minute tube" (a "mesocorallite") between the large autocorallites.  Chain corals that lack mesocorallites were assigned to a different genus, Catenipora.  "Halysites gracilis" is an out of date name, it cannot be a Halysites even according to the description you posted as it lacks mesocorallites.  You can read more about the issue in this 1955 dissertation by Edward Beuhler.

 

In fact, even the name "Catenipora gracilis" has insurmountable problems.  The original description by Hall was very cursory, so it is not clear how the species can be differentiated for many other "chain corals".  Unfortunately the type specimens Hall had in hand when he wrote the description have been lost.  Also Hall gave only a very general location for the source of the his specimens, so topotypes (material from the same locality) cannot be studied to gain an understanding of Hall's species.  However, the "coup de grace" is that Hall's name (published in 1851) is a junior synonym, as that name had already been used for a different coral by Milne-Edwards and Haime in 1849.  The unfortunate history of the name has been detailed by  G. Winston Sinclair and Thomas E. Bolton [Journal of Paleontology, Vol. 30, No. 1 (Jan., 1956), pp. 203-206.]   Once a name is used, it cannot be used for a different species.  Specimens from the Red River Formation had long been called "Halysites gracilis"; since that name is invalid Sinclair and Bolton selected a holotype specimen from a well defined locality in Southern Manitoba and named it Catenipora rubida.  It is possible that the specimen you found may also be a Catenipora rubida Sinclair & Bolton 1956, though to say so with confidence one would have to make thin sections and compare to the Red River species.  What is certain is that the name "Halysites gracilis" is invalid on multiple grounds.

 

Don

 

 

[Bev]

WOW Don!!!  Soooo, if I understood a bit of what you just said... just saying you are way smarter than I am... Halysites is an invalid name for corals. OR, is it just Halysites gracils?

 

Do you also dispute that they are in the Ordovician?

 

Caleb is the one who IDed both of mine, and he was our local expert and used that Haysites label and he was a stickler for being up to date on names. However, everyone seems to use Recepticulitids and not the new name Fisherites... Just sayin'...  :-)

[minnbuckeye]

13 hours ago, FossilDAWG said:

 One major feature is the presence of minute mesocorallites between the larger autocorallites that make up the chain.

 

Hey Bev, just see what your mesocorallites  and autocorallites look like look like and you will have your ID. Its as simple as that!!!!!!!!!!!!!!!!!  Halysites would be fine to call it when visitors come a knocking, IMO. LOL

[Bev]

4 hours ago, minnbuckeye said:

 

Hey Bev, just see what your mesocorallites  and autocorallites look like look like and you will have your ID. Its as simple as that!!!!!!!!!!!!!!!!!  Halysites would be fine to call it when visitors come a knocking, IMO. LOL

 

LOL!!! Yay, this stuff gets so technical and no one ever remembers all of the names except the experts...  Thanks Mike!  :-D

[FossilDAWG]

54 minutes ago, Bev said:

 

LOL!!! Yay, this stuff gets so technical and no one ever remembers all of the names except the experts...  Thanks Mike!  :-D

Sure, just call them whatever.  No-one cares what the actual names are.

 

Have a good day, Betty.

 

Don

[Bev]

5 hours ago, FossilDAWG said:

Sure, just call them whatever.  No-one cares what the actual names are.

 

Have a good day, Betty.

 

Don

 

Don, half the people I meet call be Deb instead of Bev and I still answer, even to "Hey woman" or the generic "Mom!"

 

But I am capable of learning a few things yet, like external mold or just fossil mold versus a fossil cast which I formerly knew is an internal mold.  :-) Please go here...