Tuesday, March 31, 2020

Devonochonetes scitulus brachiopod from the Moscow formation

In a previous post I wrote about specimens of Devonochonetes scitulus that I'd found with spines still present. The spine positions, angles, and number are the best way to differentiate between species of Devonochonetes. The previous specimens came from the Ludlowville formation and below is a specimen from the Moscow formation at the Deep Springs Rd. borrow pit. The Ludlowville underlies the Moscow formation and so is contemporaneous which means it is not unexpected to find this species at this location.

Specimen #1


Specimen #2


Here is a specimen that shows the interior of the brachial valve. The oval shapes visible are the muscle scars where the brachials would have been attached. As the brachials were not mineralized in this species, only the marks on the shell where they used to be are preserved.





These specimens were found at a borrow pit on Deep Springs Road in Madison County, NY which exposes the Windom shale member of the Moscow formation (middle Devonian in age, Givetian stage.)

Sunday, March 29, 2020

Protoleptostrophia perplana brachiopod from the Moscow formation

Protoleptostrophia perplana is not an uncommon Brachiopod fossil in the middle Devonian but what is uncommon is to be able to find an intact specimen that is not a mold in the rock.  Below is a fairly good specimen of the species that has a valve preserved in calcite. It comes from the Deep Springs Road borrow pit in near Earlville, NY.  It is not 100% intact as the margin shows a rough edge which is likely due to the very thin and fragile nature of the shell.






This specimen was found at a borrow pit on Deep Springs Road in Madison County, NY which exposes the Windom shale member of the Moscow formation (middle Devonian in age, Givetian stage.)

Friday, March 27, 2020

Calymene celebra Trilobite from the Joliet formation

Calymene celebra is the state fossil of Wisconsin and a somewhat common fossil in the white/light grey/tan Silurian aged dolostones that can be found across a number of midwest states. Rocks like this stretch from Wisconsin and Iowa down through Illinois and Indiana into Kentucky.  Below is a specimen of  Calymene celebra from the Joliet formation near Grafton Illinois. It was likely found in a quarry as productive exposures of the Joliet formation are not easy to find. 

This fossil is a cast of the interior of the trilobite exoskeleton so it's missing some of the details one would normally see.  I like this specimen due to the presence of black specks that are present. It kind of reminds me of a Dalmation dog's coat.  I think the black spots are oxidized Pyrite or Marcasite.









I've been fortunate enough to find one specimen of Calymene celebra myself. It comes from a breakwater along Lake Michigan in Milwaukee, Wisconsin where I spotted it among the rocks being used to stabilize the shoreline. It was in a small flat slab so I didn't have to smash anything to collect the specimen. You can see that it was exposed for a time as one side is smooth and some of the fossil detail has been lost.  Since the rocks had been moved from their original location, I am not sure what formation this fossil comes from.







These fossils come from the Silurian period, Llandovery stage (roughly 438-436 mya) which corresponds to the basal Niagaran series in the old N. American chronostratigraphy.

Wednesday, March 25, 2020

Hardouinia kellumi echinoid from the Pee Dee formation

Echinoids are cool critters that come in two basic flavors, regular and irregular. The regular echioids are the ones you see in aquariums and on nature shows with the long spines crawling along the bottom of the reef. Irregular echinoids are more often partially submerged in the sediment and do not have large showy spines.  Hardouinia kellumi is an example of an irregular urchin and could also be known as a sea biscuit.  The specimen below is from the Cretaceous ages sediments at Rocky Point Quarry in North Carolina. It comes from the Peedee formation which is dated to the late Maastrichtian (66-67 mya)

Adaptical surface

Anterior

Left profile

Posterior

Right profile

Adoral surface


Monday, March 23, 2020

Fossil Wasp from the Green River Formation

Here is another insect that I found in the Parachute Creek member of the Green River formation. I believe it is a wasp of the order Hymenoptera based on an image of a similar insect I found on this slide show. You can see the head, eyes, and antennae very clearly and the wings are somewhat visible too. The abdomen is not very detailed  and may not have preserved as well. I also do not see any of the legs and maybe they are preserved under the body.




I collected this fossil near the FAA radar dome in Garfield County, Colorado near Douglass Pass. The Parachute Creek member of the Green River formation is Eocene in age, Lutetian stage (about 46 mya)

Saturday, March 21, 2020

Plecia sp. fossil "March Fly" from the Green River Formation

Today I have a couple of specimens of an insect from the family Bibionidae that come from the Parachute Creek member of the Green River formation. I think they can be narrowed down to the genus Plecia but beyond that I am unsure of what species have been described from the Green River formation. The specimens that I identify as Plecia sp. have an abdomen that is at least twice as long as it is wide with wings that are as long or longer than the abdomen. The wings are rounded on the far ends resembling an oval shape.

Specimen #1



Specimen #2


Members of the genus Plecia are still found today and are often called "March Flies" or "Love Bugs" due to their appearance early in the year to mate in large swarms.

I collected these fossils at the FAA radar dome in Garfield County, Colorado near Douglass Pass. The Parachute Creek member of the Green River formation is Eocene in age, Lutetian stage (about 46 mya)

Thursday, March 19, 2020

Cricket from the Green River formation

A rare find for me from the Parachute Creek member of the Green River formation is the cricket fossil below.  Crickets belong to the family Gryllidae and generally have long bodies with round heads and six pairs of legs, a pair of which are modified to be longer than the others and are used for jumping. It's those longer legs that lead me to believe the specimen below is a cricket.  I do not know enough about crickets to be able to narrow the ID down to the genera or species, especially as I don't know what species have been described from the Green River formation.




I collected this fossil near the FAA radar dome in Garfield County, Colorado near Douglass Pass. The Parachute Creek member of the Green River formation is Eocene in age, Lutetian stage (about 46 mya)

Tuesday, March 17, 2020

Fossil Weevil from the Green River formation

Insects from the Green River formation can be difficult to ID down to a species, let alone a generic level. Often you are trying to compare a 2D fossil to 3D pictures of extant insects and all you can do is hope you are correct.  Below is a specimen I purchased because of the good preservation, but also because it had been ID'ed as a Weevil already.  I need to go through my own findings to confirm but I think I have found examples of this same kind of insect on my collecting trips.

I am still trying to find some good resources that list known insect genera from the Green River formation but they are hard to find or expensive to purchase.  At this point I can only say that this fossil is of a member of the Superfamily  Curculionidaea.


A low light shot of the fossil shows some nice details

A direct light shot shows the true color of the fossil better.

This fossil was found in the Parachute Creek shale member of the Green River formation, in Rio Blanco County, Colorado. The Green River formation is dated to the Eocene period, Lutetian stage (about 46 mya).

Check out an older post of mine where I discuss the geology of the Eocene lakes that once existed in SW Wyoming and NW Colorado.

In another one I posted some of my exceptional finds from Douglass Pass.

Sunday, March 15, 2020

Salix sp. leaf from the Green River formation

This long, narrow leaf is most likely from a member of the Willow family, Salix sp. and comes from the Parachute Creek member of the Green River formation (Eocene, Lutetian stage).  It was found in Bonanza, Utah and I purchased it because it came with an ID. I am hoping that I can use this and other identified specimens that I purchase to help ID fossils that I have found in the field. There are not many resources easily accessible that show pictures and names for plant and insect fossils from the Green River formation.  I know I have found other examples of Salix sp. that are larger and more recognizable than this specimen but I need to go through my findings and locate it.



Friday, March 13, 2020

Cardiospermum coloradensis leaf from the Green River formation

Soapberry plants are typically found in the tropics and their presence in a northerly latitude like where NE Utah is indicates that the climate used to be much warmer than it is now. Below is a leaf from the Soapberry family,  called Cardiospermum coloradensis, that is also called "Balloon Vine".   Fossils of these leaves are somewhat common in the Parachute Creek member of the Green River formation (Eocene, Lutetian stage), but most of what I have found are smaller. I purchased this piece because of the good preservation and size of the leaf.  I identified it based on this image from James St. John's Flickr page.




Wednesday, March 11, 2020

Caesalpinites sp. leaf from the Green River formation

Here is another fossil leaf from the Parachute Creek member of the Green River formation (Eocene, Lutetian stage) that I purchased because it came with an ID. It's a leaf called Caesalpinites sp.  The fossil is small and somewhat faint against the rock but you can make out the central vein and overall shape of the leaf.  This specimen comes from a site near Bonanza, Utah.  I'm having a hard time finding any more info about this genus to try and narrow down the species. I've seen other leaves labelled as Caesalpinites falcata from the same area but they look different than my specimen. It could be a different species or maybe the plant had different shaped leaves on different areas. 



Monday, March 9, 2020

Eldredgeops iowensis southworthi trilobite from the Widder formation

I don't often have luck finding trilobites as I am usually distracted by brachiopods and corals.  However a couple of years ago I managed to find the fossil shown below while searching near Arkona, Ontario.  It's a rare example of an enrolled Eldredgeops iowensis southworthi

Pics of the specimen as it was found, before cleaning.




It comes from the Hungry Hollow member of the Widder formation and the trilobites are often crushed like this one is. It still retains some 3D detail but the cephalon is all mushed up.  I wasn't even really looking for anything when I found this. I was talking to a friend and he joked that I should go find a trilobite. I glanced down at his feet and I saw this fossil sitting right on the surface. 

I gave the specimen to a friend of mine, M.T., who did a superb job of cleaning off the excess mud and matrix.

Pics in natural light







High contrast pictures



I collected this specimen from the Hungry Hollow member of the Widder formation which is Devonian is age, Givetian stage.