Micro-Bivalve

A quick post from something on the hard drive…

Often, when inspecting corals(Cnindaria) or sponges(Porifera) that I have found in the Millersburg mb. of the Lexington, I find micro-fossils at the base of the colonies. It could be coincidental, but I’m starting to think that the micros were juveniles and that their progenitor placed the off spring in a habitat that favored survival, or the ones placed there were more likely to survive… which seems more plausible.

Anyway, here is a small bivalve that was collected from just such an environment.

A little closer

Since the common bivalves from the Millersburg are modiomorphids or ambonychiids, These are probably ambonychiids… probably Bysonnychia sp. juveniles.

Enigmatic Critter

Hyolithids are a poorly understood group of critters. They first appeared in the Cambrian and became extinct during in the Great Dying(Permian-Triassic extinction) at the end of the Paleozoic. The Great Dying was the most severe crisis for the biosphere that the planet has ever experienced… about 95% of all species perished!

There are numerous hypothesis to explain the extinctions(google it), but it was probably a combination of several catastrophic changes that killed off most life.

A few hyolithids that were recovered from the Millersburg mb:

Someday, I will devote a post to the extinction event.

The Legend of Sleepy Lagoon

The “headless” trilobite:

An I. gigas that was found in the Clays Ferry Fm. in Anderson Co. Kentucky. When I found it, it was posterior-dorsal up. Wow, I was excited! Oh well…

Neat-none the less.

Ouch!

Year ago while working an outcrop that has produced some stunning asasphids, I found this little Isotelus gigas. It appears that the little guy had a bite taken out of his cephalon, enrolled and died. I found it in a bed of the Clays Ferry Fm(early Late Ordovician) in Anderson Co. Kentucky. The bed is comprised of, almost entirely, I. gigas molts and orthocerid cephalopods.

EDIT: the bar at the bottom is 1 inch(2.54cm)

Sea Monsters

Usually, brachiopods don’t get me very excited(sorry lophophorate nerds), but occasionally I come across something in the field that causes me to do a double take.

Have a look at this monster. It is an orthid brachiopod that was collected from the Millersburg Mb. of the Lexington Limestone in Fayette Co. Kentucky

Hebertella sp.

anterior

Posterior

Dorsal

Apparently, I didn’t photograph the ventral… oh, well.

I have one that is even larger! Somewhere???

Deep Water Stuff

The Ordovician of New York has been a fascination of mine since reading of C.D. Walcott’s discoveries, there, many years ago. A couple of years ago, I was granted the opportunity to visit a newly discovered lagerstatten in the Lorraine Group of Upstate New York.

The site was discovered by an amateur paleontologist from the region. In his quest to better understand the geology and paleontology of New York, he found the site that we visited, and several others that have produced stunning soft-tissue preservation of annelids and arthropods.

The Martin Quarry is located in the Whetstone Gulf Formation of the Lorraine Group in New York about 60 or 70 km north of Beecher’s Trilobite Beds. The rocks were deposited in a deep foreland basin that formed as a result of the Taconic Orogeny during the early Late Ordovician. The Late Ordovician was a time of intense tectonic activity on the Laurentian continent. As a result, the rocks of the Lorraine are characterized by sequences of turbidites.

It is within the turbidites that the exceptional preservation of the fossils are found. Bedding planes reveal hash plates with numerous partial trilobites-among other critters, but within the beds, whole critters can be found. And, if one is in the right horizon, the critters soft parts are preserved in pyrite.

Some photos:

After picking up a prep guy(one of the best in the field) at JFK, we got stuck in a traffic jam on the Tappan Zee… at 03:00!

Curiously, crinoids are absent from the locality, but they were somewhere, nearby.

The first thing that I saw when walking up to the outcrop was this lovely cephalon. The site is known for its Triarthrus fauna, and I was expecting it, but… this was the first Triarthrus that I had seen in the field! I was stoked!
photo about 15cm wide

A photo of me chopping away.

A photo of My Good Friend Who Is A Dog chillin in the creek.

A cutie(photo about 10 or 12 cm wide)

photo about 2cm wide

photo about 1.5 cm wide

Some kind of reptile… I might add, this guy shouldered(literally) a couple of tons of shale in an attempt to protect his finds, only to put on the gloves for this critter.

Probably, 75-100 partials on the slab.

Lots of partials and some other things, too. It appears that there is at least one calymenid free cheek, and a Sowerbyella brack. width of photo about 25cm

A nice ventral that is now part of the Peabody Museum collection

The guy that found this quarry developed a revolutionary an innovative technique in the preparation of pyritized soft tissue recovery… his methodology, at first, seems counter-intuitive, and maybe destructive, but his results are telling.

Further reading and references:

Beyond Beecher’s Trilobite Bed: Widespread pyritization of soft tissues in the Late Ordovician Taconic foreland basin
Farrell, et. al. 2009

Pyritization of soft-bodied fossils: Beecher’s Trilobite Bed, Upper Ordovician, New York State
Briggs, et, al. 1991

\Turbidite depositional influences on the diagenesis of Beecher’s Trilobite Bed and the Hunsrück Slate; sites of soft tissue pyritization
Raiswell, et. al. 2008

EDIT: to add photos

Unknown Critter/Flora

I have encountered this strange structure a few times in my quest to understanding the Ordovician of Kentucky. It is rarely seen, and I always ignored the thing since it didn’t seem relevant to what I was studying. Though recently, I found a few of these, intimately associated, in what might be a lagoonal environment???*

That grabbed my attention, and I submitted photos of this thing to several well known paleo-researchers. Most had no ideal, but Dr. Young clued me in! Probably, algal balls. He suggested a thin section would be determinate, but I still haven’t cut the thing.

When informed of Dr. Young’s opinion, another researcher concurred, but he hadn’t seen any, this large, from the local biota; one other was skeptical.

So, have you seen anything similar?

mag x20

These were found in a mud bed, of limited lateral extent(a few meters), interbedded within the calcarenites of the Tanglewood mb. of the Lexington Limestone.

*perhaps, that is my familiarity with the barrier islands???

Too, why can't I figure out the code of wordpress?

I’m not a ‘puter geek, but I thought that the site was HTML??? Any suggestions?

There’s Fun in the Water, But There’s Danger, Too

Recently,Callan Bentley had a post of a few critters that he had encountered, lately.

That sent the gears spinning, and I remembered a creepy crawly while at one of my favorite outcrops in Franklin Co. Ky.

In search of diplobathrids at one of my favorite outcrops, I came across this critter. It was in the spring, so it was moving slow. Still, I didn’t want to flip it over to see what the ventral looked like!

Black Widow(Lactrodectus sp.)