Posts treating: "Hungry Hollow member"
Sunday, 01 May 2016
One one of my regular trips up to Arkona, Canada I found this small scrap of fossil and hung onto to it as it reminded me of something. Well that something turns out to be a piece of a Bryozoan called Ptilopora striata (sometimes spelled Ptylipora). This bryozoan is typified by a single, strong, central "mast" with branches angling off at 45 degrees along the length. The individual branches sometimes have cross supports with neighboring branches as well. Overall the fossil has a herringbone [...]
Among the more easily identified bryozoan fossils that I found in the Bois D'Arc formation are these Lichenalia sp. examples. It's a small, encrusting fossil that I often found as loose discs. They likely started their colonies on a solid surface and could have used a crinoid segment or ostracod molt as a base. None of the examples that I found have the underside clean enough of matrix for me to tell. for sure. The fossils resemble a net with lots of small openings side by side with each other [...]
This week’s fossil is a strange one. Mr. Darrell Ellis collected the above tiny specimen from the Hungry Hollow Member (Middle Devonian) at the famous Hungry Hollow location near Arkona, Ontario. (He also took this excellent photograph.) In the classic way exploratory paleontology works, he contacted an expert, my friend Olev Vinn at the University
Among my recent finds from the Centerfield member of the Ludlowville formation is this specimen of Platycers conicum. As you can see it has a very vertical profile with little to no curving of the shell. As it is well known that some species of Platyceras were parasites of Crinoids, by stationing themselves directly above the anal pore so as to get free meals, perhaps this conical shape was adapted towards a specific Crinoid species?I've found similar examples in the Hungry Hollow member of the [...]
This is a partial pedicle valve of Spinocyrtina granulosus that I found at Hungry Hollow near Arkona, ON recently. It's very large and is the only specimen that I have of this species from the Hungry Hollow member of the Widder formation (Devonian, Givetian stage).Note the bryozoan
These next specimens are of the bryozoan Lichenalia stellata that I picked up along the shoreline of Lake Erie near Lake View, NY. They are very distinctive with a stippled surface that represents individual zooids (the space where an individual bryozoan animal lived). L. stellata appears to have been an encrusting type bryozoan and seemed to form layers as the substrate it lived upon was tossed during storm events and the colony regrew on newly exposed surfaces.Specimen #1 Specimen #2 is [...]
I found this brachiopod fossil in the Centerfield formation of New York. It looks superficially like an Ambocoelia umbonata except that the brachial valve is more convex and the sulcus is much less pronounced. Also the overall shape of the shell is slightly "fatter" than Ambocoelia. It is for these reasons that I am labeling it Emanuella praeumbona.Brachial valveAnteriorPedicle valvePosteriorProfileThe Centerfield member is a part of the Ludlowville formation and is middle Devonian (Givetian [...]
Parsing through a sample of the Centerfield Limestone looking for microfossils, I was pleasantly surprised to find some small "rice grains". They didn't look like Ostracods to me because they were not round nor did they have any ornamentation to them. A quick scan through the book "Ostracods of the Middle Devonian Silica Formation" changed my mind.These are a species called Acanthoscapa devonica. Each fossil is about 2mm long. If I did my math right, the full size image is 50x (since the [...]
I'd forgotten about this next piece until I was organizing my finds from Arkona. It's a very large portion of a bryozoan colony that came from the Hungry Hollow member of the Widder formation.Trying to determine the species would require thin sectioning of a portion so that the internal structures could be studied. Based on the "Check List of Fossil Invertebrates Described from the Middle Devonian Rocks of the Thedford-Arkona Region of Southwestern Ontario", There are three species described [...]
I have another Blastoid to add to my collection from Arkona. It's a partially crushed specimen of what I think is Devonoblastus whiteavesi. I took some pictures of the 9.5mm long specimen with my Zorb microscope camera.Crushed base of the specimenSide viewsView of the crushed side To give you an idea of scale, here is the specimen held in my fingers. Some close ups The specimen was collected from the Hungry Hollow member of the Widder formation near Arkona, Ontario, Canada. The Widder [...]
This tiny brachiopod was sifted out of some gravel that I collected from the Hungry Hollow member of the Widder formation (Devonian, Givetian stage) at Arkona. I'm not entirely sure of what it is but I'm wondering if it's a juvenile Pentamerella?
Heteroschisma canadensis is the last of the three blastoid species that I've found at Arkona. It's the smallest and is often referred to as "ice cream cones". As you can see they are about the size of rice grains so one has to be looking really close to find them. All four specimens that I found came by sifting through some eroded gravel.Oral surface (top) Side viewsBasal surface (where the stem attached)The other two species that I have from Arkona are Nucleocrinus elegans and Hyperoblastus [...]
Below are some pieces of Aulocystis from the Hungry Hollow member of the Widder formation (Devonian, Givetian) near Arkona. They are often found as loose pieces in the weathered rubble.There are three species of Aulocystis listed in the Checklist for the Hungry Hollow member of the Widder formation: A. dichotoma (Grabau), A. intermedia (Nicholson) and A. "nobilis". Of the three, A. dichotoma seems to be the best fit based on this illustration from Grabau's classic "Geology and Paleontology of [...]
While washing some Mucrospirifer fossils that I'd found at Arkona I noticed a few had some of the Bryozoan Hederella that had grown on them. I have not found many brachiopod specimens with this association at Arkona, usually it's only on Horn corals.A plate of Mucrospirifer but only one has Hederella growing on it. A loose Mucrospirifer specimen has some growths too.Another piece of a shell with some Hederella growths on it. The Mucrospirifer fossils came from the Widder formation while the [...]
Below is a relatively well preserved Pelecypod shell from an Actinopteria that I found at Arkona. It came from the Hungry Hollow member of the Widder formation which is Devonian (Givetain stage) aged. Pelcypod shells tend to dissolve faster in the rock since they are made of Aragonite so it's rare to find one that is intact or complete and this fossil may be just a mold of the original. This specimen shows some fracturing and warping of the shell on the top left side which may have occurred as [...]
Despite the Widder formation being roughly equivalent to the Silica Shale of Ohio and Michigan, Strophodonta is an uncommon fossil to find. When found they are often much smaller as well. Below is a specimen I found in July on a visit to Arkona. It's still embedded in the matrix and I'm hesitant to try and break it out for fear of shattering the fossil.Strophodonta demissa is known from the Hungry Hollow member of the Widder formation from whence this fossil came. I know that this is not a [...]
Another new species of Brachiopod for my collection from Arkona is Delthyris sculptilis. Delthyris is a common enough species within the Devonian but is uncommon in the Hungry Hollow member of the Widder formation. It has a typical Spirifer shape to the shell but it's the distinctive decoration that gives it away.Brachial valve AnteriorPedicle valvePosteriorProfileA little searching on the internet yielded this article which states that Delthyris sculptilis should be reclassified as [...]
Solitary corals always seem to catch my eye so I was pleased to receive these two specimens from my friend, Jenaro.Here are a pair of Paracunnolies undulatus from the Cretaceous (Santonian stage) near Santa Maria, Lérida, Spain. These look similar to Microcyclus thedfordensis from the Hungry Hollow member of the Widder formation in Canada. Specimen #1 Specimen #2 The other species is Diploctenium falloti from the same locality. It is shaped quite differently than the Paracunnolies above with [...]
This past July I was up collecting at Hungry Hollow near Arkona, Canada and ran into a couple of fellow fossil collectors. We chatted for a bit and one of them gave me the fossil below, a Nucleocrinus elegans.Oral surface (top) Basal surface (where the stem attached)Side viewsI think he felt bad for me as I complained that I hadn't found many blastoids at the site (despite their relative local abundance). I gave him some pieces of North Evans Limestone that are loaded with micro fossil fish and [...]
Today I'm featuring an odd bryozoan fossil that I've found as encrustations on horn corals or shells in the Hungry Hollow member of the Widder formation. The specimen below I think may be Lichenalia stellata but I'm not entirely sure.The species is known from the Hungry Hollow member, based on this book from the University of Michigan's Deep Blue Archive, and I found it listed in Grabau's book "Geology and Paleontology of 18 Mile Creek" but the only picture I can find online do not show any [...]
recommend this post
