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Showing results for tags 'Silurian age'.
Found 16 results
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Found these in a silurian deposit in Louisville, Kentucky. Any idea what they are and if they're fossils or not?
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Eurypterid lacustris collected at Port Colborne quarry. One of my best specimens- 1 comment
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- 4
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- 421 million years ago
- silurian age
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From the album: MY FOSSIL Collection - Dpaul7
Holocystites scutellatus Cystoid Osgood shale of Napoleon, Indiana Silurian Age (443 - 416 million years ago) The Holocystites Fauna is an enigmatic group of North American diploporitans that presents a rare window into unusual middle Silurian echinoderm communities. Multiple systematic revisions have subdivided holocystitids on the basis of presumed differences in oral area plating and respiratory structures. However, these differences were based on a fundamental misunderstanding of the homologous elements of the oral area and the taphonomic process; taphonomic disarticulation of the oral area formed the basis for the erection of Pentacystis and Osgoodicystis as separate genera, and Osgoodicystis is interpreted as the junior synonym of Pentacystis . Holocystitids show a conservative peristomial bordering plate pattern that is shared among all described genera. The peristome is bordered by seven interradially positioned oral plates as is typical for oral plate–bearing blastozoans. A second open circlet of facetal plates lies distal to the oral plates; five of these facetal plates bear facets for feeding appendages (lost on the A ambulacrum in some taxa), while two lateral facets (present in all taxa except Pustulocystis ) do not. Holocystitid taxa show minor modifications to this basic peristomial bordering plate pattern. As thecal morphologies are highly variable within populations, taxonomic revision of holocystitids is based on modifications of the plating of the oral area. Kingdom: Animalia Phylum: Echinodermata Subphylum: †Blastozoa Class: †Diploporita Superfamily: †Sphaeronitida Family: †Holocystitidae Genus: †Holocystites Species: †scutellatus -
From the album: MY FOSSIL Collection - Dpaul7
Holocystites scutellatus Cystoid Osgood shale of Napoleon, Indiana Silurian Age (443 - 416 million years ago) The Holocystites Fauna is an enigmatic group of North American diploporitans that presents a rare window into unusual middle Silurian echinoderm communities. Multiple systematic revisions have subdivided holocystitids on the basis of presumed differences in oral area plating and respiratory structures. However, these differences were based on a fundamental misunderstanding of the homologous elements of the oral area and the taphonomic process; taphonomic disarticulation of the oral area formed the basis for the erection of Pentacystis and Osgoodicystis as separate genera, and Osgoodicystis is interpreted as the junior synonym of Pentacystis . Holocystitids show a conservative peristomial bordering plate pattern that is shared among all described genera. The peristome is bordered by seven interradially positioned oral plates as is typical for oral plate–bearing blastozoans. A second open circlet of facetal plates lies distal to the oral plates; five of these facetal plates bear facets for feeding appendages (lost on the A ambulacrum in some taxa), while two lateral facets (present in all taxa except Pustulocystis ) do not. Holocystitid taxa show minor modifications to this basic peristomial bordering plate pattern. As thecal morphologies are highly variable within populations, taxonomic revision of holocystitids is based on modifications of the plating of the oral area. Kingdom: Animalia Phylum: Echinodermata Subphylum: †Blastozoa Class: †Diploporita Superfamily: †Sphaeronitida Family: †Holocystitidae Genus: †Holocystites Species: †scutellatus -
From the album: MY FOSSIL Collection - Dpaul7
Holocystites scutellatus Cystoid Osgood shale of Napoleon, Indiana Silurian Age (443 - 416 million years ago) The Holocystites Fauna is an enigmatic group of North American diploporitans that presents a rare window into unusual middle Silurian echinoderm communities. Multiple systematic revisions have subdivided holocystitids on the basis of presumed differences in oral area plating and respiratory structures. However, these differences were based on a fundamental misunderstanding of the homologous elements of the oral area and the taphonomic process; taphonomic disarticulation of the oral area formed the basis for the erection of Pentacystis and Osgoodicystis as separate genera, and Osgoodicystis is interpreted as the junior synonym of Pentacystis . Holocystitids show a conservative peristomial bordering plate pattern that is shared among all described genera. The peristome is bordered by seven interradially positioned oral plates as is typical for oral plate–bearing blastozoans. A second open circlet of facetal plates lies distal to the oral plates; five of these facetal plates bear facets for feeding appendages (lost on the A ambulacrum in some taxa), while two lateral facets (present in all taxa except Pustulocystis ) do not. Holocystitid taxa show minor modifications to this basic peristomial bordering plate pattern. As thecal morphologies are highly variable within populations, taxonomic revision of holocystitids is based on modifications of the plating of the oral area. Kingdom: Animalia Phylum: Echinodermata Subphylum: †Blastozoa Class: †Diploporita Superfamily: †Sphaeronitida Family: †Holocystitidae Genus: †Holocystites Species: †scutellatus -
From the album: MY FOSSIL Collection - Dpaul7
Holocystites scutellatus Cystoid Osgood shale of Napoleon, Indiana Silurian Age (443 - 416 million years ago) The Holocystites Fauna is an enigmatic group of North American diploporitans that presents a rare window into unusual middle Silurian echinoderm communities. Multiple systematic revisions have subdivided holocystitids on the basis of presumed differences in oral area plating and respiratory structures. However, these differences were based on a fundamental misunderstanding of the homologous elements of the oral area and the taphonomic process; taphonomic disarticulation of the oral area formed the basis for the erection of Pentacystis and Osgoodicystis as separate genera, and Osgoodicystis is interpreted as the junior synonym of Pentacystis . Holocystitids show a conservative peristomial bordering plate pattern that is shared among all described genera. The peristome is bordered by seven interradially positioned oral plates as is typical for oral plate–bearing blastozoans. A second open circlet of facetal plates lies distal to the oral plates; five of these facetal plates bear facets for feeding appendages (lost on the A ambulacrum in some taxa), while two lateral facets (present in all taxa except Pustulocystis ) do not. Holocystitid taxa show minor modifications to this basic peristomial bordering plate pattern. As thecal morphologies are highly variable within populations, taxonomic revision of holocystitids is based on modifications of the plating of the oral area. Kingdom: Animalia Phylum: Echinodermata Subphylum: †Blastozoa Class: †Diploporita Superfamily: †Sphaeronitida Family: †Holocystitidae Genus: †Holocystites Species: †scutellatus -
From the album: MY FOSSIL Collection - Dpaul7
Hemitoechia perryvillensis Brachiopod Brownsport Formation along Hwy. 641 in Decatur County, Tennessee Silurian age (443 - 416 million years ago) The taxonomic order Rhynchonellida is one of the two main groups of living articulate brachiopods, the other being the order Terebratulida. They are recognized by their strongly ribbed wedge-shaped or nut-like shells, and the very short hinge line. The hinges come to a point, a superficial resemblance to many (phylogenetically unrelated) bivalve mollusk shells. The loss of the hinge line was an important evolutionary innovation, rhynchonellids being the first truly non-strophic shells with a purely internal articulation (teeth-sockets). Strong radiating ribs are common in this group; and there are generally very strong plications or accordion-like folds on the sulcus (the long middle section) of the shell. This probably helps regulate the flow of water in and out of the shell. All rhynchonellids are biconvex (have a bulbous shell), and have a fold located in the brachial valve. This means that the commissure, the line between the two valves or shells, is zigzagged, a distinguishing characteristic of this group. The prominent beak of the pedicle valve usually overlaps that of the brachial valve, in order to allow the shell to open and close. There is usually a functional pedicle although the delthyrium may be partially closed. Morphologically, the rhynchonellid has changed little since its appearance during the Ordovician period. It seems to have evolved from pentamerids, and in turn gave rise to the first atrypids and athyrids, both of which are characterized by the development of a complex spiral brachidium. Although much diminished by the terminal Paleozoic extinction, it experienced a revival during the Early Jurassic period, and became the most abundant of all brachiopods during the Mesozoic Era. Kingdom: Animalia Pylum: Brachiopoda Class: Rhynchonellata Order: Rhynchonellida Family: †Trigonirhynchiidae Genus: †Hemitoechia Species: †perryvillensis -
From the album: MY FOSSIL Collection - Dpaul7
Hemitoechia perryvillensis Brachiopod Brownsport Formation along Hwy. 641 in Decatur County, Tennessee Silurian age (443 - 416 million years ago) The taxonomic order Rhynchonellida is one of the two main groups of living articulate brachiopods, the other being the order Terebratulida. They are recognized by their strongly ribbed wedge-shaped or nut-like shells, and the very short hinge line. The hinges come to a point, a superficial resemblance to many (phylogenetically unrelated) bivalve mollusk shells. The loss of the hinge line was an important evolutionary innovation, rhynchonellids being the first truly non-strophic shells with a purely internal articulation (teeth-sockets). Strong radiating ribs are common in this group; and there are generally very strong plications or accordion-like folds on the sulcus (the long middle section) of the shell. This probably helps regulate the flow of water in and out of the shell. All rhynchonellids are biconvex (have a bulbous shell), and have a fold located in the brachial valve. This means that the commissure, the line between the two valves or shells, is zigzagged, a distinguishing characteristic of this group. The prominent beak of the pedicle valve usually overlaps that of the brachial valve, in order to allow the shell to open and close. There is usually a functional pedicle although the delthyrium may be partially closed. Morphologically, the rhynchonellid has changed little since its appearance during the Ordovician period. It seems to have evolved from pentamerids, and in turn gave rise to the first atrypids and athyrids, both of which are characterized by the development of a complex spiral brachidium. Although much diminished by the terminal Paleozoic extinction, it experienced a revival during the Early Jurassic period, and became the most abundant of all brachiopods during the Mesozoic Era. Kingdom: Animalia Pylum: Brachiopoda Class: Rhynchonellata Order: Rhynchonellida Family: †Trigonirhynchiidae Genus: †Hemitoechia Species: †perryvillensis -
From the album: MY FOSSIL Collection - Dpaul7
Caryocrintes Cystoid bulb Rochester Shale Formation, Orleans County, New York, USA Silurian age (443 - 416 million years ago) The cystoid bulb measures 1 1/8” long and 1 1/8” wide and was prepared free of matrix. This fossil is covered with bryozoan. A Cystoid is any member of an extinct class (Cystoidea) of primitive echinoderms (animals with a hard, calcareous external skeleton, related to the modern sea lily and starfish) that first appeared during the Middle Ordovician Epoch and persisted into the Late Devonian Epoch (the Ordovician Period began about 488 million years ago, and the Devonian Period ended 359 million years ago). Once diverse and important, the cystoids had saclike bodies that were attached to a stem anchored to the seafloor. Numerous plates covered the body. Some forms are important guide, or index, fossils and thus allow the correlation of sometimes widely separated rock units. Kingdom: Animalia Phylum: Echinodermata Subphylum: Pelmatozoa Class: †Cystoidea Subclass: †Rhombifera Superfamily: †Hemicosmitida Family: †Caryocrinitidae Genus: †Caryocrinites -
From the album: MY FOSSIL Collection - Dpaul7
Caryocrintes Cystoid bulb Rochester Shale Formation, Orleans County, New York, USA Silurian age (443 - 416 million years ago) The cystoid bulb measures 1 1/8” long and 1 1/8” wide and was prepared free of matrix. This fossil is covered with bryozoan. A Cystoid is any member of an extinct class (Cystoidea) of primitive echinoderms (animals with a hard, calcareous external skeleton, related to the modern sea lily and starfish) that first appeared during the Middle Ordovician Epoch and persisted into the Late Devonian Epoch (the Ordovician Period began about 488 million years ago, and the Devonian Period ended 359 million years ago). Once diverse and important, the cystoids had saclike bodies that were attached to a stem anchored to the seafloor. Numerous plates covered the body. Some forms are important guide, or index, fossils and thus allow the correlation of sometimes widely separated rock units. Kingdom: Animalia Phylum: Echinodermata Subphylum: Pelmatozoa Class: †Cystoidea Subclass: †Rhombifera Superfamily: †Hemicosmitida Family: †Caryocrinitidae Genus: †Caryocrinites -
From the album: MY FOSSIL Collection - Dpaul7
Caryocrintes Cystoid bulb Rochester Shale Formation, Orleans County, New York, USA Silurian age (443 - 416 million years ago) The cystoid bulb measures 1 1/8” long and 1 1/8” wide and was prepared free of matrix. This fossil is covered with bryozoan. A Cystoid is any member of an extinct class (Cystoidea) of primitive echinoderms (animals with a hard, calcareous external skeleton, related to the modern sea lily and starfish) that first appeared during the Middle Ordovician Epoch and persisted into the Late Devonian Epoch (the Ordovician Period began about 488 million years ago, and the Devonian Period ended 359 million years ago). Once diverse and important, the cystoids had saclike bodies that were attached to a stem anchored to the seafloor. Numerous plates covered the body. Some forms are important guide, or index, fossils and thus allow the correlation of sometimes widely separated rock units. Kingdom: Animalia Phylum: Echinodermata Subphylum: Pelmatozoa Class: †Cystoidea Subclass: †Rhombifera Superfamily: †Hemicosmitida Family: †Caryocrinitidae Genus: †Caryocrinites -
From the album: MY FOSSIL Collection - Dpaul7
Caryocrintes Cystoid bulb Rochester Shale Formation, Orleans County, New York, USA Silurian age (443 - 416 million years ago) The cystoid bulb measures 1 1/8” long and 1 1/8” wide and was prepared free of matrix. This fossil is covered with bryozoan. A Cystoid is any member of an extinct class (Cystoidea) of primitive echinoderms (animals with a hard, calcareous external skeleton, related to the modern sea lily and starfish) that first appeared during the Middle Ordovician Epoch and persisted into the Late Devonian Epoch (the Ordovician Period began about 488 million years ago, and the Devonian Period ended 359 million years ago). Once diverse and important, the cystoids had saclike bodies that were attached to a stem anchored to the seafloor. Numerous plates covered the body. Some forms are important guide, or index, fossils and thus allow the correlation of sometimes widely separated rock units. Kingdom: Animalia Phylum: Echinodermata Subphylum: Pelmatozoa Class: †Cystoidea Subclass: †Rhombifera Superfamily: †Hemicosmitida Family: †Caryocrinitidae Genus: †Caryocrinites -
From the album: MY FOSSIL Collection - Dpaul7
Caryocrintes Cystoid bulb Rochester Shale Formation, Orleans County, New York, USA Silurian age (443 - 416 million years ago) The cystoid bulb measures 1 1/8” long and 1 1/8” wide and was prepared free of matrix. This fossil is covered with bryozoan. A Cystoid is any member of an extinct class (Cystoidea) of primitive echinoderms (animals with a hard, calcareous external skeleton, related to the modern sea lily and starfish) that first appeared during the Middle Ordovician Epoch and persisted into the Late Devonian Epoch (the Ordovician Period began about 488 million years ago, and the Devonian Period ended 359 million years ago). Once diverse and important, the cystoids had saclike bodies that were attached to a stem anchored to the seafloor. Numerous plates covered the body. Some forms are important guide, or index, fossils and thus allow the correlation of sometimes widely separated rock units. Kingdom: Animalia Phylum: Echinodermata Subphylum: Pelmatozoa Class: †Cystoidea Subclass: †Rhombifera Superfamily: †Hemicosmitida Family: †Caryocrinitidae Genus: †Caryocrinites -
From the album: MY FOSSIL Collection - Dpaul7
Scyphocrinites (aka Mahaoumacrinites) Crinoid Erfoud, Morocco Upper Silurian in age (420 million years old) Crinoids are marine animals that make up the class Crinoidea of the echinoderms (phylum Echinodermata). The name comes from the Greek word krinon, "a lily", and eidos, "form". Scyphocrinus, is an extinct genus of crinoids. Species belonging to this genus live in the Silurian and Devonian periods (from 443.4 to 358.9 Ma). Kingdom: Animalia Phylum: Echinodermata Subphylum: Crinozoa Class: Crinoidea Subclass: Camerata Order: †Monobathrida Genus: †Scyphocrinus -
From the album: MY FOSSIL Collection - Dpaul7
Scyphocrinites (aka Mahaoumacrinites) Crinoid Erfoud, Morocco Upper Silurian in age (420 million years old) Crinoids are marine animals that make up the class Crinoidea of the echinoderms (phylum Echinodermata). The name comes from the Greek word krinon, "a lily", and eidos, "form". Scyphocrinus, is an extinct genus of crinoids. Species belonging to this genus live in the Silurian and Devonian periods (from 443.4 to 358.9 Ma). Kingdom: Animalia Phylum: Echinodermata Subphylum: Crinozoa Class: Crinoidea Subclass: Camerata Order: †Monobathrida Genus: †Scyphocrinus -
I went down to south central Ohio near Dayton and Ludlow Falls for a Fossil hunting trip organized by our Fossil club, the North Coast Fossil Club out of the Cleveland Ohio area. Our hunt was planned for Saturday 8/29/15, and I was able to go down Friday for an extra day of fossil hunting around the Dayton and Xenia areas. Friday was a bust, the area I planned to hunt north of the Wright Bros. memorial looked very good but I could not get to it. Dirt road was overgrown, too far for me to walk, and not about to scratch up my brand new Ford Edge, 2000 miles, no way. So, I went over to the Xenia area to check out the road cuts on OH 42 south. That was a flop, very little left to collect between Xenia and Waynesville. Saturday morning we all met at the Quarry (not naming because access is getting very restricted) north of Dayton. Expecting to hunt the same area we were at two years ago, I was glad to see we were going to a new part of the quarry; things are looking up. Not so much, I can see everyone moving around and not finding anything worth picking up. Time to move further along the cut. This is all newly blasted, Silurian age Dolomite that has not seen light for the last 430 million years. What I and the rest are finding is there was not much alive that became fossilized in this area either. It is beginning to look like another disappointing fossil hunting trip to this Quarry. I am finding some of the large Pentamerid brachiopods, and a nice section of a straight cephalopod, split long ways. It would of polished up nice, but was left behind. One of the members said that the Women farther down had found some Trilobites. Off I go to see what was found. These were a few nice prone Calymene Trilobites. These were on a light tan sandstone type of Dolomite that was splitting in two to three inch thick sections. Usually at this quarry, you bring your bigger sledgehammers and spend a lot of time busting rock hopping to find a surprise, bug. This was very interesting. I went up the blast pile, which was mostly gray here, with some of the tan in areas. Up on top of the pile apx. 25 to 30 feet high and in the swale, I would call it; was a lot of this tan stone in thinner sheets. I start a more thorough search of this stone and a nice prone Calymene trilobite. OK, I found “ONE”. That usually makes it a great trip. Waite! What is this, another one??? Can’t be, that’s not my luck. Another one!!! I must be dreaming, you only read about other people doing this. Another one? This is getting serious. OK! Things are getting strange for me, I am building up a stack of stones with prone and full molds of Trilobites. This is not the usual trilobite pieces and parts, usually tail sections or an occasional head; these are all full Trilobites except where the rock split through it. This area must be one of the mass mortality areas you only read about. I look around to see who is around I can call over, this is too good for just one person; too many trilobites in too big of an area, I need to get more members here to get in on the fun. Great luck, I see one of our newest members of the Forum and our Fossil club, Velociraptor99. I yell out to him, to carefully climb up where I am, I want to show him something. Being new, he is wanting a trilobite, like we all do. He gets up where I am, and I show him what I am finding, and he is thrilled. I show him what he is looking for, what kind of stone to look for what he is looking for and send him over 10 feet away. There is no need to send him far away, there are too many bugs right here. I also tell him to also check out the loose dirt, sand and ground stone between the rocks for rollers. It only takes a few minutes till him let out a holler that he found one, than he calls out he found a lose one, in great shape. Then another. He is thrilled for being 16 and on his first big quarry trip. I give him a piece of orange marking tape to put on his growing pile of Trilobites so they don’t get lost in the excitement. Ok, Time to call in more members there are more to share, Hey everyone come on over. The members that made it over ALL had a memorable trip after this find. I have over twenty Trilobites that should be very close to full prone or slightly bent after they get prepped out. Of the full molds, I hope to make casts of the missing bugs. High explosives have a tendency of being rough on fossils, but many of these are beautiful. Short info: This area is the Cedarville formation – Dolomite Pentamerid brachiopods are found near contact with the Springfield Dolomite This are is Silurian age, Dolomite Wenlockian age, 430/433 million years old Some of the Calymene Trilobites I found.
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- Calymene Trilobite
- Cedarville formation
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