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Found 38 results

  1. My daughter was recently out in Wyoming for a dig (she's the real paleontologist in the family) and brought back these belemnites. These are out of the Sundance Formation. I'm use to the specimens coming out of Big Brook NJ (Mount Laurel formation). I find it interesting that the specimens coming out of Wyoming generally appear larger (length and girth) than their NJ cousins. Also, the Wyoming specimens are more "rockish" looking while the Big Brook specimens have an amber hue to them. Visually, I would say that for both specimens the Outline is cylindrical and the Profile is symmetrical. The Apex varies from acute to more rounded.
  2. Zugodactylites braunianum 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Zugodactylites braunianum Ammonite Schleifhausen, Germany Jurassic Period (201.3-145 Million Years Ago) Zugodactylites is an extinct genus of cephalopods belonging to the Ammonite subclass. It has lived during lower Jurassic, lower Toarcian, ammonite zone Fibulatum. Its fossils were found in Europe, Russia and Canada. Whorl section of shells belonging these ammonites were compressed, equidimensional or depressed. Before aperture of adult shell, there has been collar and constriction. Ribs were dense and they were bifurcating at sharp ventrolateral tubercules or spines. There were no fibulate ribs. Sexual dimorphism is known, and Gabillytes, synonym of Zugodactylites were microconchs. They have evolved from finely ribbed Peronoceras. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Superfamily: †Eoderoceratoidea Family: †Dactylioceratidae Subfamily: †Dactylioceratinae Genus: †Zugdactylites Species: †braunianus
  3. Zugodactylites braunianum 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Zugodactylites braunianum Ammonite Schleifhausen, Germany Jurassic Period (201.3-145 Million Years Ago) Zugodactylites is an extinct genus of cephalopods belonging to the Ammonite subclass. It has lived during lower Jurassic, lower Toarcian, ammonite zone Fibulatum. Its fossils were found in Europe, Russia and Canada. Whorl section of shells belonging these ammonites were compressed, equidimensional or depressed. Before aperture of adult shell, there has been collar and constriction. Ribs were dense and they were bifurcating at sharp ventrolateral tubercules or spines. There were no fibulate ribs. Sexual dimorphism is known, and Gabillytes, synonym of Zugodactylites were microconchs. They have evolved from finely ribbed Peronoceras. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Superfamily: †Eoderoceratoidea Family: †Dactylioceratidae Subfamily: †Dactylioceratinae Genus: †Zugdactylites Species: †braunianus
  4. Perisphinctes sp Ammonite B1.JPG

    From the album MY FOSSIL Collection - Dpaul7

    Perisphinctes sp Ammonite Madagascar Jurassic Period (199.6 to 145.5 million years ago) Perisphinctes is an extinct genus of ammonite cephalopod. They lived during the Late Jurassic Epoch, and serve as an index fossil for that time period. Shells of species belonging to this genus have been found in the Jurassic of Antarctica, Argentina, Chile, Cuba, Egypt, Ethiopia, France, Germany, Hungary, India, Iran, Italy, Japan, Madagascar, Poland, Portugal, Russia, Saudi Arabia, Spain, Switzerland, the United Kingdom and Yemen. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Family: †Perisphinctidae Genus: †Perisphinctes
  5. Perisphinctes sp Ammonite B1.JPG

    From the album MY FOSSIL Collection - Dpaul7

    Perisphinctes sp Ammonite Madagascar Jurassic Period (199.6 to 145.5 million years ago) Perisphinctes is an extinct genus of ammonite cephalopod. They lived during the Late Jurassic Epoch, and serve as an index fossil for that time period. Shells of species belonging to this genus have been found in the Jurassic of Antarctica, Argentina, Chile, Cuba, Egypt, Ethiopia, France, Germany, Hungary, India, Iran, Italy, Japan, Madagascar, Poland, Portugal, Russia, Saudi Arabia, Spain, Switzerland, the United Kingdom and Yemen. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Family: †Perisphinctidae Genus: †Perisphinctes
  6. Harpoceras falcifer Ammonite 1.JPG

    From the album MY FOSSIL Collection - Dpaul7

    Harpoceras falcifer Ammonite Morocco Jurassic Period (201.3-145 million years ago) Harpoceras is an extinct genus of cephalopod belonging to the family Hildoceratidae. These cephalopods existed in the Jurassic period, during Toarcian age from Falciferum zone to Commune subzone of Bifrons zone. They were fast-moving nektonic carnivores. Shells of Harpoceras species show strong dimorphism in their size. While microconchs reach 24–51 mm in diameter, macroconchs shells width is 115–430 mm. They are moderately evolute to involute and compressed. Whorl sides are flat and there is strong keel. Ribs are falcoid or falcate and thus biconcave, strong and projected. Sometimes, ribs can be broad and flat topped on outer part of whorl and in some species they can be striate on inner part of whorl. Some species have midlateral groove, or series of undulating depressions on inner half of whorl. Fossils of species within this genus have been found in the Early Jurassic rocks of Europe, Northern Africa, Russia, Japan, Borneo, New Zealand, Indonesia, North and South America. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Suborder: †Ammonitina Superfamily: †Hildoceratoidea Family: †Hildoceratidae Subfamily: †Harpoceratinae Genus: †Harpoceras Species: †falciferum
  7. Harpoceras falcifer Ammonite 1.JPG

    From the album MY FOSSIL Collection - Dpaul7

    Harpoceras falcifer Ammonite Morocco Jurassic Period (201.3-145 million years ago) Harpoceras is an extinct genus of cephalopod belonging to the family Hildoceratidae. These cephalopods existed in the Jurassic period, during Toarcian age from Falciferum zone to Commune subzone of Bifrons zone. They were fast-moving nektonic carnivores. Shells of Harpoceras species show strong dimorphism in their size. While microconchs reach 24–51 mm in diameter, macroconchs shells width is 115–430 mm. They are moderately evolute to involute and compressed. Whorl sides are flat and there is strong keel. Ribs are falcoid or falcate and thus biconcave, strong and projected. Sometimes, ribs can be broad and flat topped on outer part of whorl and in some species they can be striate on inner part of whorl. Some species have midlateral groove, or series of undulating depressions on inner half of whorl. Fossils of species within this genus have been found in the Early Jurassic rocks of Europe, Northern Africa, Russia, Japan, Borneo, New Zealand, Indonesia, North and South America. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Suborder: †Ammonitina Superfamily: †Hildoceratoidea Family: †Hildoceratidae Subfamily: †Harpoceratinae Genus: †Harpoceras Species: †falciferum
  8. Harpoceras falcifer Ammonite 1.JPG

    From the album MY FOSSIL Collection - Dpaul7

    Harpoceras falcifer Ammonite Morocco Jurassic Period (201.3-145 million years ago) Harpoceras is an extinct genus of cephalopod belonging to the family Hildoceratidae. These cephalopods existed in the Jurassic period, during Toarcian age from Falciferum zone to Commune subzone of Bifrons zone. They were fast-moving nektonic carnivores. Shells of Harpoceras species show strong dimorphism in their size. While microconchs reach 24–51 mm in diameter, macroconchs shells width is 115–430 mm. They are moderately evolute to involute and compressed. Whorl sides are flat and there is strong keel. Ribs are falcoid or falcate and thus biconcave, strong and projected. Sometimes, ribs can be broad and flat topped on outer part of whorl and in some species they can be striate on inner part of whorl. Some species have midlateral groove, or series of undulating depressions on inner half of whorl. Fossils of species within this genus have been found in the Early Jurassic rocks of Europe, Northern Africa, Russia, Japan, Borneo, New Zealand, Indonesia, North and South America. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Suborder: †Ammonitina Superfamily: †Hildoceratoidea Family: †Hildoceratidae Subfamily: †Harpoceratinae Genus: †Harpoceras Species: †falciferum
  9. Harpoceras falcifer Ammonite 1.JPG

    From the album MY FOSSIL Collection - Dpaul7

    Harpoceras falcifer Ammonite Morocco Jurassic Period (201.3-145 million years ago) Harpoceras is an extinct genus of cephalopod belonging to the family Hildoceratidae. These cephalopods existed in the Jurassic period, during Toarcian age from Falciferum zone to Commune subzone of Bifrons zone. They were fast-moving nektonic carnivores. Shells of Harpoceras species show strong dimorphism in their size. While microconchs reach 24–51 mm in diameter, macroconchs shells width is 115–430 mm. They are moderately evolute to involute and compressed. Whorl sides are flat and there is strong keel. Ribs are falcoid or falcate and thus biconcave, strong and projected. Sometimes, ribs can be broad and flat topped on outer part of whorl and in some species they can be striate on inner part of whorl. Some species have midlateral groove, or series of undulating depressions on inner half of whorl. Fossils of species within this genus have been found in the Early Jurassic rocks of Europe, Northern Africa, Russia, Japan, Borneo, New Zealand, Indonesia, North and South America. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Suborder: †Ammonitina Superfamily: †Hildoceratoidea Family: †Hildoceratidae Subfamily: †Harpoceratinae Genus: †Harpoceras Species: †falciferum
  10. Harpoceras falcifer Ammonite 1.JPG

    From the album MY FOSSIL Collection - Dpaul7

    Harpoceras falcifer Ammonite Morocco Jurassic Period (201.3-145 million years ago) Harpoceras is an extinct genus of cephalopod belonging to the family Hildoceratidae. These cephalopods existed in the Jurassic period, during Toarcian age from Falciferum zone to Commune subzone of Bifrons zone. They were fast-moving nektonic carnivores. Shells of Harpoceras species show strong dimorphism in their size. While microconchs reach 24–51 mm in diameter, macroconchs shells width is 115–430 mm. They are moderately evolute to involute and compressed. Whorl sides are flat and there is strong keel. Ribs are falcoid or falcate and thus biconcave, strong and projected. Sometimes, ribs can be broad and flat topped on outer part of whorl and in some species they can be striate on inner part of whorl. Some species have midlateral groove, or series of undulating depressions on inner half of whorl. Fossils of species within this genus have been found in the Early Jurassic rocks of Europe, Northern Africa, Russia, Japan, Borneo, New Zealand, Indonesia, North and South America. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Suborder: †Ammonitina Superfamily: †Hildoceratoidea Family: †Hildoceratidae Subfamily: †Harpoceratinae Genus: †Harpoceras Species: †falciferum
  11. From the album MY FOSSIL Collection - Dpaul7

    Belemnite Phragmocone and part of the Pro-Ostracum Germany Jurassic Period (201.3-145 million years ago) Belemnitida (or belemnites) is an extinct order of cephalopods which existed during the Mesozoic era, from the Hettangian age of the Lower Jurassic to the Maastrichtian age of the Upper Cretaceous. The belemnite is the state fossil of Delaware. Belemnites studded with small inward-curving hooks used for grasping prey. However, they lacked the pair of specialized tentacles present in modern squid. Belemnites (and other belemnoids) were distinct from modern squid by possessing hard internal skeletons. The internal skeleton was composed of the guard or rostrum (plural: rostra), a heavy solid structure at the posterior of the animals. The rostrum was usually bullet-shaped and projects prominently backward, but in the suborder Belemnotheutina, it was only present as a thin layer. While the inherited camerate portion of the internal skeleton (see below) was of aragonite, the evolutionarily novel rostrum was composed of calcite. Due to its more geologically stable calcite constitution, the rostrum is often the only remains of the animals preserved, often in very large numbers in a given area. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Clade:†Belemnoidea Order: †Belemnitida
  12. From the album MY FOSSIL Collection - Dpaul7

    Belemnite Phragmocone and part of the Pro-Ostracum Germany Jurassic Period (201.3-145 million years ago) Belemnitida (or belemnites) is an extinct order of cephalopods which existed during the Mesozoic era, from the Hettangian age of the Lower Jurassic to the Maastrichtian age of the Upper Cretaceous. The belemnite is the state fossil of Delaware. Belemnites studded with small inward-curving hooks used for grasping prey. However, they lacked the pair of specialized tentacles present in modern squid. Belemnites (and other belemnoids) were distinct from modern squid by possessing hard internal skeletons. The internal skeleton was composed of the guard or rostrum (plural: rostra), a heavy solid structure at the posterior of the animals. The rostrum was usually bullet-shaped and projects prominently backward, but in the suborder Belemnotheutina, it was only present as a thin layer. While the inherited camerate portion of the internal skeleton (see below) was of aragonite, the evolutionarily novel rostrum was composed of calcite. Due to its more geologically stable calcite constitution, the rostrum is often the only remains of the animals preserved, often in very large numbers in a given area. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Clade:†Belemnoidea Order: †Belemnitida
  13. From the album MY FOSSIL Collection - Dpaul7

    Belemnite Phragmocone and part of the Pro-Ostracum Germany Jurassic Period (201.3-145 million years ago) Belemnitida (or belemnites) is an extinct order of cephalopods which existed during the Mesozoic era, from the Hettangian age of the Lower Jurassic to the Maastrichtian age of the Upper Cretaceous. The belemnite is the state fossil of Delaware. Belemnites studded with small inward-curving hooks used for grasping prey. However, they lacked the pair of specialized tentacles present in modern squid. Belemnites (and other belemnoids) were distinct from modern squid by possessing hard internal skeletons. The internal skeleton was composed of the guard or rostrum (plural: rostra), a heavy solid structure at the posterior of the animals. The rostrum was usually bullet-shaped and projects prominently backward, but in the suborder Belemnotheutina, it was only present as a thin layer. While the inherited camerate portion of the internal skeleton (see below) was of aragonite, the evolutionarily novel rostrum was composed of calcite. Due to its more geologically stable calcite constitution, the rostrum is often the only remains of the animals preserved, often in very large numbers in a given area. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Clade:†Belemnoidea Order: †Belemnitida
  14. Gulielmites jason Ammonite 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Gulielmites jason Ammonite Kellaways Sandstone, England Jurassic Period (201.3-145 million years ago) Kosmoceratidae is an extinct ammonite family from the Callovian (Middle Jurassic) to Early Cretaceous. Kosmoceratidae are probably the most polymorphic groups of Jurassic ammonites. These ammonoids have a more or less tabulate venter, with lateral or ventrolateral tubercles. The aptychus is double valved with a concentrically ribbed surface. Ecology: fast-moving nektonic carnivore. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Family: †Kosmoceratidae Genus: †Gulielmites Species: †jason
  15. Gulielmites jason Ammonite 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Gulielmites jason Ammonite Kellaways Sandstone, England Jurassic Period (201.3-145 million years ago) Kosmoceratidae is an extinct ammonite family from the Callovian (Middle Jurassic) to Early Cretaceous. Kosmoceratidae are probably the most polymorphic groups of Jurassic ammonites. These ammonoids have a more or less tabulate venter, with lateral or ventrolateral tubercles. The aptychus is double valved with a concentrically ribbed surface. Ecology: fast-moving nektonic carnivore. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Family: †Kosmoceratidae Genus: †Gulielmites Species: †jason
  16. Gulielmites jason Ammonite 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Gulielmites jason Ammonite Kellaways Sandstone, England Jurassic Period (201.3-145 million years ago) Kosmoceratidae is an extinct ammonite family from the Callovian (Middle Jurassic) to Early Cretaceous. Kosmoceratidae are probably the most polymorphic groups of Jurassic ammonites. These ammonoids have a more or less tabulate venter, with lateral or ventrolateral tubercles. The aptychus is double valved with a concentrically ribbed surface. Ecology: fast-moving nektonic carnivore. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Family: †Kosmoceratidae Genus: †Gulielmites Species: †jason
  17. Gulielmites jason Ammonite 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Gulielmites jason Ammonite Kellaways Sandstone, England Jurassic Period (201.3-145 million years ago) Kosmoceratidae is an extinct ammonite family from the Callovian (Middle Jurassic) to Early Cretaceous. Kosmoceratidae are probably the most polymorphic groups of Jurassic ammonites. These ammonoids have a more or less tabulate venter, with lateral or ventrolateral tubercles. The aptychus is double valved with a concentrically ribbed surface. Ecology: fast-moving nektonic carnivore. Kingdom: Animalia Phylum: Mollusca Class: Cephalopoda Subclass: †Ammonoidea Order: †Ammonitida Family: †Kosmoceratidae Genus: †Gulielmites Species: †jason
  18. gastrolith 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Gastrolith Utah Jurassic Period (199.6 to 145.5 million years ago) A gastrolith, also called a stomach stone or gizzard stones, is a rock held inside a gastrointestinal tract. Gastroliths in some species are retained in the muscular gizzard and used to grind food in animals lacking suitable grinding teeth. In other species the rocks are ingested and pass through the digestive system and are frequently replaced. The grain size depends upon the size of the animal and the gastrolith's role in digestion. Other species use gastroliths as ballast. Particles ranging in size from sand to cobbles have been documented. Some extinct animals such as sauropod dinosaurs appear to have used stones to grind tough plant matter. A rare example of this is the Early Cretaceous theropod Caudipteryx zoui from northeastern China, which was discovered with a series of small stones, interpreted as gastroliths, in the area of its skeleton that would have corresponded with its abdominal region. Aquatic animals, such as plesiosaurs, may have used them as ballast, to help balance themselves or to decrease their buoyancy, as crocodiles do.
  19. gastrolith 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Gastrolith Utah Jurassic Period (199.6 to 145.5 million years ago) A gastrolith, also called a stomach stone or gizzard stones, is a rock held inside a gastrointestinal tract. Gastroliths in some species are retained in the muscular gizzard and used to grind food in animals lacking suitable grinding teeth. In other species the rocks are ingested and pass through the digestive system and are frequently replaced. The grain size depends upon the size of the animal and the gastrolith's role in digestion. Other species use gastroliths as ballast. Particles ranging in size from sand to cobbles have been documented. Some extinct animals such as sauropod dinosaurs appear to have used stones to grind tough plant matter. A rare example of this is the Early Cretaceous theropod Caudipteryx zoui from northeastern China, which was discovered with a series of small stones, interpreted as gastroliths, in the area of its skeleton that would have corresponded with its abdominal region. Aquatic animals, such as plesiosaurs, may have used them as ballast, to help balance themselves or to decrease their buoyancy, as crocodiles do.
  20. Stephanoceras (Normannites) sp 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Stephanoceras (Normannites) sp. Ammonite Bajocian, Morocco Jurassic period ( 201.3 -145 million years ago) Stephanoceras (meaning crown horn) is an extinct genus of Stephanoceratoid ammonite which lived during the Bajocian (Middle Jurassic). It is the type genus of the family Stephanoceratidae. Stephanoceras has an evolute shell, as characteristic of the family, with well-developed ribbing and tubercles. The shell is coiled so whorls barely touch in most, but some have notable overlap. Primary ribs emerge from the umbilical seam, the line marking the inner edge of the particular exposed whorl, and divide on the flanks, usually in two, occasionally in three, forming secondary ribs that cross the outer rim of the shell, known as the venter, uninterrupted. Turbercles, elevated projections, form at the ends of the primary ribs where they bifurcate or sometimes trifurcate. Stephanoceras grew to be fairly large with a shell diameter as much as 27 cm and width as much as 6 cm across the outer whorl. Like many ammonites, Stephanoceras is dimorphic with a large, macroconch, form thought to be female and a small, microconch, form thought to be male. In most aspects the microconch is simply a smaller version of the macroconch. The primary difference lies in the aperture, which in the microconch has planar extensions on either side, lappets. That of the macroconch is generally simple, preceded by a constriction. Kingdom: Animalia Pylum: Mollusca Class: Cephalopoda Order: †Ammonitida Family: † Stephanoceratidae
  21. Stephanoceras (Normannites) sp 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Stephanoceras (Normannites) sp. Ammonite Bajocian, Morocco Jurassic period ( 201.3 -145 million years ago) Stephanoceras (meaning crown horn) is an extinct genus of Stephanoceratoid ammonite which lived during the Bajocian (Middle Jurassic). It is the type genus of the family Stephanoceratidae. Stephanoceras has an evolute shell, as characteristic of the family, with well-developed ribbing and tubercles. The shell is coiled so whorls barely touch in most, but some have notable overlap. Primary ribs emerge from the umbilical seam, the line marking the inner edge of the particular exposed whorl, and divide on the flanks, usually in two, occasionally in three, forming secondary ribs that cross the outer rim of the shell, known as the venter, uninterrupted. Turbercles, elevated projections, form at the ends of the primary ribs where they bifurcate or sometimes trifurcate. Stephanoceras grew to be fairly large with a shell diameter as much as 27 cm and width as much as 6 cm across the outer whorl. Like many ammonites, Stephanoceras is dimorphic with a large, macroconch, form thought to be female and a small, microconch, form thought to be male. In most aspects the microconch is simply a smaller version of the macroconch. The primary difference lies in the aperture, which in the microconch has planar extensions on either side, lappets. That of the macroconch is generally simple, preceded by a constriction. Kingdom: Animalia Pylum: Mollusca Class: Cephalopoda Order: †Ammonitida Family: † Stephanoceratidae
  22. Playdellia sp 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Pleydellia sp. Ammonite Bajocian, Morocco Jurassic period ( 201.3 -145 million years ago) Hildoceratidae is a family of ammonoid cephalopods from the Lower Jurassic, lower Pliensbachian (Jamesoni zone) to lower Bajocian (maybe even upper Bajocian) substages, generally with strongly ribbed, involute shells. They are combined with the Hammatoceratidae (= Phymatoceratidae), Graphoceratidae, and Sonniniidae to make up the Hildoceratoidea. Kingdom: Animalia Pylum: Mollusca Class: Cephalopoda Order: †Ammonitida Family: †Hildoceratidae Genus: †Pleydellia
  23. Playdellia sp 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Pleydellia sp. Ammonite Bajocian, Morocco Jurassic period ( 201.3 -145 million years ago) Hildoceratidae is a family of ammonoid cephalopods from the Lower Jurassic, lower Pliensbachian (Jamesoni zone) to lower Bajocian (maybe even upper Bajocian) substages, generally with strongly ribbed, involute shells. They are combined with the Hammatoceratidae (= Phymatoceratidae), Graphoceratidae, and Sonniniidae to make up the Hildoceratoidea. Kingdom: Animalia Pylum: Mollusca Class: Cephalopoda Order: †Ammonitida Family: †Hildoceratidae Genus: †Pleydellia
  24. Phlycticeras sp 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Phlycticeras sp. Ammonite Bajocian, Morocco Jurassic period ( 201.3 -145 million years ago) The Strigoceratidae is a family in the ammonitid superfamily Haploceratoidea, restricted to the lower Middle Jurassic, Bajocian stage, possibly derived from the Hammitoceratidae. The family was established and named by Buckman in 1924. The shells of the Strigoceratidae are compressed to oxyconic, with a narrow or minute umbilicus and simple or irregularly branched ribbing almost confined to the outer (ventral) half of the whorl sides. The sutures are moderately simple to complex, with a long umbilical lobe bearing a graded series of Auxiliaries. Kingdom: Animalia Pylum: Mollusca Class: Cephalopoda Order: †Ammonitida Family: †Strigoceratidae Genus: †Phlycticeras
  25. Phlycticeras sp 1.jpg

    From the album MY FOSSIL Collection - Dpaul7

    Phlycticeras sp. Ammonite Bajocian, Morocco Jurassic period ( 201.3 -145 million years ago) The Strigoceratidae is a family in the ammonitid superfamily Haploceratoidea, restricted to the lower Middle Jurassic, Bajocian stage, possibly derived from the Hammitoceratidae. The family was established and named by Buckman in 1924. The shells of the Strigoceratidae are compressed to oxyconic, with a narrow or minute umbilicus and simple or irregularly branched ribbing almost confined to the outer (ventral) half of the whorl sides. The sutures are moderately simple to complex, with a long umbilical lobe bearing a graded series of Auxiliaries. Kingdom: Animalia Pylum: Mollusca Class: Cephalopoda Order: †Ammonitida Family: †Strigoceratidae Genus: †Phlycticeras
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