Category: Fossil Friday
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Fossil Friday #320: Tully Monster Repeat!
For this week’s Fossil Friday, we’re featuring our first-ever repeat fossil. It was special before and you’ll see why it’s even more special now. This remarkable Tully Monster specimen comes from longtime ESCONI member Jeremy Zimmerman. You could even say that this particular fossil is getting its third chance at fame.
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Fossil Friday #319: First Tully!
Back in late March, I went fossil collecting with a couple Field Museum researchers, including Lazaro Viñola López (see “Ancient bees found nesting inside fossil bones in rare cave discovery” for some of his recent work), a postdoctoral researcher. This was his first trip to Pit 11. Bet you can guess where this is headed…
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Fossil Friday #318: Rex, the Wonder Amphibian
We have something very interesting this week… The specimen’s label says “Rex, the Wonder Amphibian”. It’s an early tetrapod from the Mississippian of Iowa, some 340 million years ago. Whatcheeria deltae was described by R. Eric Lombard and John R. Bolt in 1985 in the paper “A new primitive tetrapod, Whatcheeria deltae, from the Lower…
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Fossil Friday #317: Silurian Aquatic Scorpion From the Kokomo Limestone
This undescribed aquatic scorpion dates to the Silurian Period and was collected by Sam Ciurca from the Kokomo Limestone at Yeoman Quarry near Kokomo, Indiana, in 1975. Measuring about 2 inches in length, this animal is extraordinarily rare, with only a handful of specimens known.
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Fossil Friday #315: Eubleptus danielsi
Eubleptus danielsi belongs to the Palaeodictyoptera an extinct order of medium-sized to very large, primitive Palaeozoic paleopterous insects. E. danielsi was described by Anton Handlirsch in 1906. Handlirsch (1865 – 1935) was an Austrian entomologist, who worked extensively on many insect orders. He did significant work studying of fossil insects. Handlirsch described E. danielsi in “Revision of American Paleozoic insects. Proceedings of…
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Fossil Friday #314: Kellibrooksia macrogaster
For today’s fossil, we have a beautiful specimen of Kellibrooksia macrogaster, which was a species of mantis shrimp (see Mazon Monday #105). This rare animal was described by Frederick Schram in 1973. It was named in honor of Harold Kelly Brooks, who published the first well-illustrated modern account of Mazon Creek crustaceans. A pdf of his work is…
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Fossil Friday #313: Mazonomya mazonensis
George Witaszek sent us this breathtaking plate platter of Mazonomya mazonensis (see Mazon Monday #25). This animal was called “clam-clam” by collectors. Mazonomya mazonensis was known incorrectly as Edmondia for a long time. It was redescribed by Jack Bailey in the book “Paleobiology, Paleoecology, and Systematics of Solemyidae (Mollusca: Bivalvia: Protobranchia) from the Mazon Creek…
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Fossil Friday #312: Sublepidophloios protuberans with a spray of Cyperites bicarinatus
At first glance, today’s fossil might look like a cone. But, closer examination reveals it to be a nice specimen of Sublepidophloios protuberans with a spray of Cyperites bicarinatus at the top. Sublepidophloios protuberans is a species of lycopsid branch (see Mazon Monday #316) and Cyperites bicarinatus was the sterile leaves for the Lycopsida (see Mazon…
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Fossil Friday #311: Dung Beetle Balls from the Oligocene
Today’s contribution comes from our old friend Ralph Jewell. Back in the 1990s, Ralph was interested in the Oligocene fossils of the Brule Formation, which dates to 34-40 million years ago. This region is sometimes referred to as the White River as the Brule Formation is a member of the White River Group.
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Fossil Friday #310: Mazon Creek Scallop
Another small concretion with a treasure inside… this one has a scallop (see Mazon Monday #35). This one is Aviculopecten mazonensis. There’s no information about where this concretion was collected, but Pit 11 is very likely. We ran across it while preparing for the 2026 ESCONI Show. Do you think these were as tasty as…
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Fossil Friday #309: Acanthotelson stimpsoni
Today, we have a cute little Acanthotelson stimpsoni (see Mazon Monday #52) from the Mazon River. Acanthotelson stimpsoni is a syncarid shrimp. It’s the most common shrimp found in the Braidwood fauna.
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Fossil Friday #308: Beautiful things in small packages…
For this week, we have a nice and detailed orbicular pinnule from a Macroneuropteris scheuchzeri. The concretion is very small., but the “hairs” are there. Unfortunately, they may not show up in the photos. This concretion was collected from Pit 2 and opened via freeze/thaw. Check out the last photo to see the size and…
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Fossil Friday #307: Euphoberia sp. From Pit 11
For today, we have a very nice Mazon Creek millipede. Euphoberia is an extinct genus of millipede found in both Europe and North America. The genus was erected by Fielding Bradford Meek and Amos Henry Worthen when they described Euphoberia armigera as a centipede in 1868.
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Fossil Friday #306: Cyclus obesus
Just earlier this week, Mazon Monday #310 was about Cyclus obesus. That post was triggered by Mike Monteith’s recent find. On one of the nice days last week, Mike was going through his freeze/thaw from this winter and found this very nice Cyclus obesus. Thanks for sharing, Mike!
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Fossil Friday #305: A Beautiful Receptaculites/Fisherites!
This is the “Fossil Friday” post #305. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! Taking a little break from Mazon Creek fossils this week…
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Fossil Friday #304: A Heartwarming Tully Reunion
This is the “Fossil Friday” post #304. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! For Valentines Day, we have a nice heartwarming Tullymonster reunion…
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Fossil Friday #303: Mounted Pecopteris notata
This is the “Fossil Friday” post #303. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! Today, we have one of the rarer forms, Pecopteris notata.…
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Fossil Friday #302: A Beautiful Macroneuropteris scheuchzeri from Braceville!
This is the “Fossil Friday” post #302. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! For this week, we have a beautiful pyritized Macroneuropteris sheuchzeri…
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Fossil Friday #301: French Palaeocaris
This is the “Fossil Friday” post #301. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! In Mazon Monday #294, we highlighted the fossil site at…
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Fossil Friday #300: Orthotarbus robustus from the River
This is the “Fossil Friday” post #300. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! Is there a better way to post our 300th Fossil…
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Fossil Friday #299: Annularia sphenophylloides
This is the “Fossil Friday” post #299. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! Today, we have another beautiful contribution from George Witaczek. This time…
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Fossil Friday #298: Seed Fern Fiddlehead – Spiropteris
This is the “Fossil Friday” post #298. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! This week’s Fossil Friday features a fiddlehead — the coiled…
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Fossil Friday #297: Alethopteris serlii
This is the “Fossil Friday” post #297. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! This week’s Fossil Friday is a favorite of many…
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Fossil Friday #296: Roachoid Wing from the Creek
This is the “Fossil Friday” post #296. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! This beautiful roachoid wing was collected from the Mazon…
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Fossil Friday #295: Juvenile Dvinosaur From Mazon Creek
This is the “Fossil Friday” post #295. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! We have a particularly special Mazon Creek fossil to share…
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Fossil Friday #294: Phenopterum briggsi
This is the “Fossil Friday” post #294. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! Phenopterum briggsi is a grylloblattidan species of insect from the…
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Fossil Friday #293: Mazon Creek Lepidodendron Cones from the River
This is the “Fossil Friday” post #293. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! We have a couple rare and beautiful cones from the…
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Fossil Friday 292: Annularia inflata From the Past
This is the “Fossil Friday” post #292. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! Michele Micetich, curator at the Carbon Hill School Museum in…
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Fossil Friday #291: Carboniferous Fish in Black Shale
This is the “Fossil Friday” post #291. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! This week’s Fossil Friday is a detailed Carboniferous fish fossil…
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Fossil Friday #290: Cyclopteris orbicularis
This is the “Fossil Friday” post #290. Expect this to be a regular feature of the website. We will post fossil pictures you send in to esconi.info@gmail.com. Please include a short description or story. Check the #FossilFriday Bluesky/Twitter hash tag for contributions from around the world! We have a beautiful Cyclopteris orbicularis from Knob Noster for…