Fossils/Invertebrates

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Main article: Fossils

Sponges (Phylum Porifera)

Porifera.jpg
Common Names Sponges
Physical Description Their bodies do not contain tissue, muscles, nerves, or organs. Some are composed of silica spicules, and others of calcium carbonate.
Fossil Range Precambrian to Recent. Sponges reached their greatest diversity during the Cretaceous period.
Mode of Life/Habitat They are benthic and sessile, and live in marine environments.
Adaptations over Time They were the first to branch off from the common ancestor of all animals, so they're the sister group of all other animals. The shapes of their bodies are adapted for maximal efficiency of water flow through the central cavity.
Distribution Sponges are worldwide in their distribution, living in a wide range of ocean habitats.
Additional Information They pump water through the body to feed, and have one body orifice to serve for ingestion as well as excretion.
Taxonomy
Kingdom Animalia.

Genus Astraeospongia (calcareous sponge)

Starsponge.png
Common Names Basket Sponge
Fossil Range Silurian to Devonian
Mode of Life/Habitat It lived in marine environments.
Additional Information It was a calcareous sponge- that is, it was composed mostly of calcium carbonate. The spicules were the only part of the sponge that got fossilized, and there are star-shapes spicules all over the body (though they can be faint). The pores of the sponge are called Ostium.
Taxonomy
Class: Heteractinida
Order: Octactinellida


Genus Hydnoceras (glass sponge)

Hydnoceras.GIF
Common Names Glass Sponge
Physical Description It is composed of silica spicules, which provided structural support and deterred enemies.
Fossil Range Devonian to Pennsylvanian
Distribution Eastern United States and Europe
Additional Information Glass sponges are extant, but are now found only in the deep ocean. In the past, they could be found at almost all depths


Bryozoans (Phylum Bryozoa)

Bryofossil.jpg
Common Names Moss animals
Physical Description The structure seen when looking at a Bryozoan is actually a support structure composed of calcium carbonate. The animal itself lives in tiny holes in that structure, and is rarely larger than a millimeter. They appear very similar to corals, but are very, very different in biology. Bryozoans come in three growth forms: massive (a mound with no planned shape), branching (where the structure forms intricate branches), and fenestrate (where in life the bryozoan would have large, soft appendages coming out from the skeleton).
Fossil Range They evolved in the Ordovician, and are still found today. Are most commonly found in Paleozoic rocks
Mode of Life/Habitat They attached to the bottom of the ocean, and were filter feeders.
Distribution Bryozoans are found on every continent except Antarctica. Most lived in a shallow marine environment, but nowadays can also be found in fresh water.
Additional Information The produce a compound known as bryostatin 1, which is currently being tested as an anti-cancer drug. Bryozoans can reproduce both sexually and asexually.
Taxonomy
Clade Lophophorata


Genus Archimedes
Archie.jpg
Physical Description It was a fenestrate bryozoan that was much wider in life than it seems from the fossil. Individual animals are called zooids.
Fossil Range Carbonifererous.
Mode of Life/Habitat It was a filter feeder, than was benthic and sessile in nature.
Distribution Are mainly found throughout Europe and North America, but they have also been found in sediments of Afghanistan, Canada, Russia, and Australia. They lived in shallow marine waters - the prefered clear water because murky water clogs zooecium.
Additional Information It was named for the Greek thinker Archimedes, who invented the water screw - Genus Archimedes looks very much like a screw.
Taxonomy
Class: Stenolaemata
Order: Fenestrata
Family: Fenestellidae


Genus Rhombopora
Rhombopora.png
Physical Description A branching bryozoan.
Fossil Range Carboniferous to Permian.
Mode of Life/Habitat Sessile, benthic, filter feeder.
Distribution North America, shallow marine waters.
Additional Information It was a branching bryozoan.
Taxonomy
Class: Stenolaemata
Order: Rhabdomesida
Family: Rhomboporidae

Graptolites (Phylum Hemichordata)

Graptolites.jpg
Common Names Graptolites
Physical Description Fossils look like pencil marks on a rock. They consisted of colonies of microscopic organisms with a threefold body division.
Fossil Range Cambrian to end of Carboniferous.
Mode of Life/Habitat Usually deposit feeders, though some species are filter feeders.
Adaptations over Time They are thought to be on the path that led to the vertebrates.
Distribution Worldwide - excellent index fossils for the Paleozoic.
Additional Information They are usually fossilized by means of carbonization in shale.
Taxonomy
Clade: Ambulacraria

Order Dendroidea (benthic graptolites)

Dendroidea.jpeg
Common Names Benthic Graptolites
Physical Description They were upright and bushy. They are many-branched, with numerous small thecae (two kinds of thecae, autothecae and bithecae)
Fossil Range Middle Cambrian to Lower Carboniferous
Mode of Life/Habitat Sessile, Benthic, Suspension Feeder.
Distribution Worldwide.

Order Graptoloidea (planktic graptolites)

Graptolites.jpg
Common Names Planktic Graptolites
Physical Description One type of thecae (autothecae). In adults, there is always a sicula bearing a nema.
Fossil Range Lower Ordovician to Lower Devonian
Mode of Life/Habitat Planktonic/Pelagic, Sessile, Suspension Feeder.
Adaptations over Time They had 8 stipes in earlier forms but 2 and then 1 in later forms.
Distribution Worldwide.
Additional Information More diverse than Dendroidea.

Corals (Phylum Cnidaria)

Cnidaria.png Jellyfossil.png
Mode of Life/Habitat Corals are benthic, whereas jellyfish are planktonic.
Distribution Shallow marine
Additional Information The cnidarian group contains jellyfish, sea anemones, and corals. They all use stinging cells known as nematocysts to capture prey, which is usually plankton. Modern corals have a symbiotic relationship with algae.


Order Tabulata (tabulate corals)

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Common Names Tabulate Corals
Physical Description They form colonies of hexagonal cells (corallites), with a calcite skeleton. They have well-developed horizontal internal partitions (tabulae) within each cell, but reduced or absent vertical internal partitions (septa).
Fossil Range Ordovician to Permian. They became extinct in the Permian–Triassic extinction event.
Mode of Life/Habitat They were almost always colonial.
Distribution Shallow waters.
Additional Information Horn corals get their name from their body shape, which is horn-like.
Taxonomy
Phylum Cnidaria, Class Anthozoa. Corals are divided into two groups for this event- horn corals and colonial corals.


Genus Favosites
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Common Names Honeycomb coral.
Physical Description A specimen can be anywhere from a few centimeters to tens of centimeters in all dimensions. Is easily recognizable by the honeycomb-like appearance when viewed from above. Corallites (individual structure that houses each coral animal/polyp) were about 1/16 in (2mm) wide and in length they were long, narrow, closely packed tubes. They were colonial.
Fossil Range Ordovician to Devonian. It is commonly found in Silurian limestone.
Adaptations over Time Rising sea levels during the Devonian caused them to become less common.
Distribution Worldwide - warm, shallow water. Mostly found in Michigan.
Taxonomy
Family Favositidae


Genus Halysites
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Common Names Chain coral, due to its growth pattern.
Physical Description Made of calcite. Individual corallites were 1/16 in (2 mm) long and wide held a single polyp. Corallites are more widely spaced in Halysites than in many other tabulate corals.
Fossil Range Mid Ordovician to Late Silurian. They thrived in the Silurian.
Adaptations over Time They had a symbiotic relationship with hermit crabs and algae.
Distribution Lived in warm, shallow waters. They have been found in sediments of Canada, the US, and Australia.
Additional Information It is an index fossil for the Silurian.
Taxonomy
Family Halysitidae

Order Rugosa (rugose corals)

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Common Names Horn Corals.
Physical Description They have a skeleton made of calcite. They have bilateral symmetry (tabulate and scleractinian corals have radial symmetry)
Fossil Range Middle Ordovician to Late Permian.
Mode of Life/Habitat Benthic microcarnivores.
Adaptations over Time Some symbiotic rugose corals were endobionts of Stromatoporoidea.


Genus Heliophylum (horn coral)
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Physical Description It fed using its nematocysts to stun prey.
Fossil Range Devonian.
Mode of Life/Habitat It was solitary, not colonial.
Distribution They had a wide distribution.
Additional Information Heliophyllum was a solitary horn coral


Genus Hexagonaria
Colcoral.jpg
Common Names The polished stone of this fossil is known as a Petoskey Stone, and is the state stone of Michigan.
Physical Description A colonial rugose coral. Each corallite of the Hexagonaria is made up of a usually six-sided compartment that adjoins the others in the colony and creates an elaborate hexagon.
Fossil Range Devonian.
Distribution It was very widely distributed around the world and lived in warm, shallow waters.
Additional Information It is the state fossil of Michigan. It was very widely distributed around the earth.

Order Scleratinia (stony corals)

Scleractinia.jpg
Physical Description The skeleton of an individual scleractinian polyp is known as a corallite. All modern scleractinian skeletons are composed of calcium carbonate in the form of crystals of aragonite
Fossil Range Middle Triassic - Recent. Scleractinian corals are the only corals that are alive today.
Mode of Life/Habitat Although some species are solitary, most are colonial.
Distribution They live in every ocean in the world. Hermatypic corals live in shallow tropical waters while Ahermatypic corals live in all regions of the ocean.
Additional Information Polyps reproduce asexually by budding.


Genus Septastrea
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Physical Description Septastraea's morphology is variable, being able to grow into just about any shape. Corallites were 1/4 inches long and wide.
Fossil Range It lived from the Miocene to the Pleistocene during the Neogene and Quaternary periods.
Mode of Life/Habitat Usually lived in shallow, warm water, but were able to survive in deeper, colder water.


Arthropods (Phylum Arthropoda)

Arthropoda.jpg
Physical Description They are invertebrates and have segmented bodies, an exoskeleton, and many limbs. The exoskeleton is made of chitin and sometimes calcium carbonate.
Fossil Range Cambrian - Recent.
Additional Information This is the phylum that contains the "creepy-crawlies" of today. Arachnids, insects, and the like are all arthropods.


Subphylum Crustacea (shrimp, lobster, crabs, barnacles, ostracods)
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Physical Description Their shell is made of chitin. Their bodies are divided into segments - the head, thorax, and abdomen (sometimes referred to as the cephalothorax and abdomen). They have gills to obtain oxygen. They have 2 pairs of sensory antennae and 3 pairs of limbs used to push food into the mouth. They moult their exoskeleton in order to grow. They have an open circulatory system.
Fossil Range Cambrian - Recent. They became abundant from Carboniferous period onward
Mode of Life/Habitat They are aquatic and carnivorous.
Distribution The majority are aquatic (either marine or freshwater) but a few groups have adapted to live on land.


Subphylum Chelicerata (Eurypterids)
A systematic diagram of a eurypterid's anatomy
Common Names Sea Scorpions
Physical Description They are the largest-known arthropods ever to exist, the largest measuring in at 2.5 meters long (although most were less than 8 inches long).
Fossil Range Middle Ordovician - Late Permian (Although the earliest fossils of eurypterids date back to the Ordovician, the level of complexity already exhibited by the group indicates that they evolved in the Cambrian). After being heavily affected by the Late Devonian extinction, they became extinct during the Permian-Triassic extinction. Eurypterids were most diverse during the Devonian and Silurian periods.
Additional Information When they were first discovered, paleontologists thought that they were ancient catfish- it was seven years later that they became identified as arthropods. More detail is known about the external anatomy of eurypterids than any other group of fossils, and they are almost as well known as modern animals.
Taxonomy
The eurypterids belonged to the same group that modern-day horseshoe crabs are classified in. As arachnids, they are related to modern day spiders and scorpions.

Class Insecta (Insects)

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Physical Description Their bodies have a head, thorax, and abdomen. They have six legs attached to the thorax. Insects began as wingless organisms, but evolved wings in the Carboniferous. They have a waterproof exoskeleton made of chitin
Fossil Range Early Devonian to recent. By the Cretaceous, all modern forms of insects had appeared.
Mode of Life/Habitat Terrestrial and freshwater.
Distribution Worldwide
Additional Information Many undergo metamorphosis in the change from one stage of life to another. Insects were not visibly affected by the extinction of the dinosaurs at the end of the Cretaceous.

Class Trilobita (Trilobites)

Trisections.pngTrilobes.png
Physical Description The first image identifies the sections of a trilobite's body: 1- cephalon, 2-Throax, 3-pygidium. The second image identifies the lobes that gives trilobites their name: 1- Left pleural, 2-Axial, 3-Right pleural.

Trilobites are named for their bodies, which are divided into three lobes, which run longitudinally along the body. The trilobite's body is also divided into three sections. They had legs, which were probably made of chitin, and antennae. Trilobites had spikelike structures on each side of the cephalon known as "free cheeks", which fell off during molting.

Fossil Range They were widespread from the Cambrian to the Permian, but fell victim to the huge mass extinction at the end of the Permian period. They were the most diverse at the end of the Cambrian.
Mode of Life/Habitat Most of them lived benthically, but some may have been planktonic. Most of them were detritus feeders, but some may have been active predators and scavengers. They lived in the ocean - after the Ordovician, they moved from shallow water to deep water.
Distribution They are good index fossils.
Additional Information This is the major class of arthropods competitors will be asked about.
Taxonomy
There are four genera of Trilobite that competitors are responsible for identifying.


Genus Cryptolithus
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Common Names It is also known as the "lace collar trilobite", because the front edge of its cephalon looks somewhat like lace.
Physical Description It was almost completely blind. It is easily identifiable by its long free cheeks, and its unbelievably squashed appearance. Cryptolithus was a small trilobite. The thorax has 6 segments.
Fossil Range Ordovician
Mode of Life/Habitat Probably just ate detritus on the bottom of the ocean.
Additional Information Its name comes from Latin: Crypto means “hidden” and lithus means “stone.”


Genus Calymene
Calymene.jpg
Physical Description It is typically 2 cm in length. They have a Holochroal eye. Most have 13 segments in the thorax, but some have 19 segments. The cephalon is the widest part of the oragnism. They are frequently preserved as tightly rolled fossils.
Fossil Range Early Ordovician to Early Devonian. They were the most abundant in the Silurian.
Mode of Life/Habitat They lived in a marine environment - both shallow and deep.
Distribution North America, North Africa, and Europe.
Additional Information It is the state fossil of Wisconsin. Its name means “beautiful crescent”.


Genus Elrathia
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Physical Description It is identifiable by its small head and well-defined axial lobe. Its thorax has anywhere from twelve to seventeen segments.
Fossil Range Middle Cambrian - oldest trilobite on the list.
Distribution It is widespread in Western US and North America. It is commonly found in the Wheeler Formation in Utah.
Additional Information Its name is based off the town Elrath, Cherokee County, Alabama, where they were discovered.


Genus Isotelus
Isotelus.png
Physical Description It was the largest trilobite- three species of Isotelus grew to almost a meter long, and Isotelus rex is world’s largest trilobite ever found as a complete fossil. It also possessed pits around the body that some think housed sensory hairs. The thorax had 8 segments. It had Holochroal eyes.
Fossil Range Middle-Upper Ordovician
Mode of Life/Habitat Shallow and deep marine.
Distribution Restricted to Europe and North America
Additional Information Isotelus maximus is Ohio’s state fossil.


Genus Eldredgeops (formerly Phacops)
Phacops.png
Physical Description It had schizochroal eyes, and a proparian facial structure. Its thorax had 11 segments.
Fossil Range Late Middle to early Upper Devonian. It was the most abundant in Devonian - used as a index fossil for the Devonian period.
Mode of Life/Habitat Warm, shallow seas.
Distribution It is found in North America, Morocco, and USA.
Additional Information Eldredgeops rana is Pennsylvania's state fossil. Fossils are commonly found rolled in a ball, probably for self protection.

Brachiopods (Phylum Brachiopoda)

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Common Names Lamp Shells
Physical Description Brachiopods are a diverse group of lophophorates that are externally very similar to clams and other bivalves. They are divided into two groups- inarticulate and articulate.
Taxonomy
As lophophorates, their closest relatives are bryozoans.

Class Inarticulata

Physical Description Most inarticulate brachiopods are less than 1 cm in size - smaller than articulate brachiopods. Their shells were composed of calcium phosphate. They lack the tooth and socket arrangement between the valves that is present in articulate brachiopods.
Fossil Range Cambrian - recent.
Mode of Life/Habitat Although they were originally shallow marine organisms, today's brachiopods are only found in the deep ocean. They could be either epifaunal or infaunal in nature, depending on the species. They were filter feeders.
Distribution Worldwide


Genus Lingula
Lingula.jpg
Common Names Name means "Little Tongue" in Latin because of its thin, tongue-shaped shell.
Physical Description It is known for having a very long pedicle, which anchored it to the sea floor. It can be detected by a short row of three openings through which it takes in water (sides) and expels it again (middle).
Fossil Range Silurian to recent.
Mode of Life/Habitat It lived in vertical burrows in intertidal areas and fed on detritus.
Additional Information It is the oldest known animal genus.

Class Articulata

Arti.jpg Culate.jpg
Physical Description Articulate brachiopods have two valves that are different size. The larger shell is called the pedicle valve - contains a hole through which a fleshy stalk called a pedicle attaches to a substrate (rocks or sediment on the sea floor). The pedicle acts as an anchor that firmly holds the brachiopod in place. Brachiopods are immobile throughout adult life. The pedicle valve contains projections called teeth, which fit into sockets on the opposite brachial valve.
Fossil Range Cambrian to recent. They flourished during Paleozoic (570-240 mya) and Mesozoic (240-65 mya) eras.
Mode of Life/Habitat Most live in moderately deep water. They are sessile benthic suspension feeders.
Additional Information They make up 95% of known brachiopod genera


Genus Atrypa
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Physical Description Atrypa is a genus of brachiopod with shells round to short egg-shaped, covered with many fine radial ridges, that split further out. Shells are usually around 1cm in length.
Mode of Life/Habitat Habitat was shallow water and soft substrates.
Distribution Atrypa can be found on every continent except Antarctica.
Taxonomy
Lower Silurian (more specifically Telychian) to Upper Devonian (specifically Frasnian)


Genus Composita
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Common Names Composita is also called Athyris
Physical Description 1 in (25 mm) long and wide. Composita had a smooth shell with a more or less distinct fold and sulcus and a round opening for the pedicle on the pedicle valve. Given the smooth shell, it was perfectly suited to survive in turbulent environments. Its shell is made of calcite.
Fossil Range Found from the Upper Devonian to the Permian - especially abundant in Permian deposits.
Mode of Life/Habitat It was abundant in warm, shallow seas.
Distribution It is widespread in North America.
Additional Information They are often present in rock with much shell debris.


Genus Juresania
Juresania.jpg
Physical Description It was about 16 mm long and 22 mm wide. It had a round outline, a convex ventral, and was covered with numerous small spines. These small spines were found on both halves of the shell, and are the easiest way to identify Juresania. It had very fine costae.
Fossil Range Carboniferous (Pennsylvanian) to Late Permian.
Mode of Life/Habitat Juresania was a suspension feeder in a marine environment.
Distribution Nebraska, Kansas, Oklahoma, Texas, Nevada
Additional Information Juresania is common in Beattie limestone and mostly in limestone or shale.


Genus Leptaena
Leptaena.jpg
Physical Description It is best identified by concentric wrinkling in the shell, which is finely striated. The ridges are used to stabilize it in soft substrates. It is fan shaped.
Fossil Range Ordovician to Permian.
Mode of Life/Habitat It adapted to living in sediment by lying flat, allowing sediment to gather on top of it. Marine environment.
Distribution Widespread in North America, China, Norway and UK.
Additional Information Commonly found in Wenlock limestone


Genus Mucrospirifer
Mucrospirifer.jpg
Common Names Butterfly Shells.
Physical Description Shell was typically 2.5 cm, but could grow up to 4 cm. Mucrospirifer was strophic, meaning that it had a well defined hinge.
Fossil Range Ordovician through Jurassic - mainly existed in the Devonian. They survived the Permian extinction.
Mode of Life/Habitat Soft, muddy, marine sediments
Adaptations over Time They had a big, long shell for the large surface area to prevent sinking into the mud and would help separate in-flowing and out-flowing currents.
Distribution Worldwide distribution.
Additional Information "Mucrospirifer" means “sharply pointed spire-bearer”


Genus Platystrophia
Platystrophia.jpg
Physical Description 3/4 in (19 mm) long, 1¼ in (32 mm) wide. Their shells were made out of calcite, and they lost their pedicles as they aged. Each valve of the shell is convex in profile, and the hinge line between the valves is wide. Surface markings on the shell include prominent angular ridges and intervening linear depressions.
Fossil Range Middle Ordovician through Upper Silurian
Mode of Life/Habitat They lived in quiet intertidal zones - shallow and deep marine.
Distribution Worldwide


Genus Rafinesquina
Rafinesquina.png
Common Names Nicknamed the "Cursed Brachiopod."
Physical Description Rafinesquina was 22 mm long and 28 mm wide. Their valves were flat and thin. They are "D" shaped, have concave brachial valve, and a convex pedicle valve. They have fine costae.
Fossil Range Middle/Upper Ordovician
Adaptations over Time Good index fossil for the Ordovician.
Distribution Widespread in North America
Additional Information Named to honor Professor Constantine Rafinesque

Order Rhynchonellida

Rhynchonellida.jpg
Physical Description They have small, distinctive shells made out of calcium phosphate, often with highly inflated valves.
Fossil Range Middle Ordovician to Recent. In the Mesozoic, they were the most abundant brachiopod.
Adaptations over Time They were the first articulate brachiopod.
Additional Information Rhynchonellida are a still living order of brachiopods that first began to appear in the Ordovician. They can be identified by their wedge shape, and large ridges. They are biconvex, and have changed little since their appearance in the Ordovician.


Mollusks (Phylum Mollusca)

Class Bivalvia (clams, oysters, mussels)

Physical Description Bivalves are a still living class of mollusks that include oysters, clams, mussels, and scallops. Their shells are either made of aragonite or calcite. They are usually bilaterally symmetrical. They may look superficially like brachiopods.
Fossil Range Early Cambrian - Recent. The first freshwater bivalves appeared in the Devonian.
Mode of Life/Habitat Mostly marine - some live in lakes and streams. Many bivalves burrow into the sediment. Bivalves can be shallow infaunal, deep infaunal, or epifaunal.
Additional Information "Bivalvia" means "two valves."


Genus Exogyra
Exogyra.jpg
Physical Description About 4 inches long and wide. The left valve is deep while the right valve is flat - they are asymmetrical. Their shells are very durable and made of aragonite.
Fossil Range Jurassic to Cretaceous.
Mode of Life/Habitat Solid substrates in warm seas. They were sessile filter feeders.
Distribution Worldwide
Additional Information Many of them survived as fossils due to the thick shells which were not easily destroyed.


Genus Gryphaea
Gryphaea.jpg
Physical Description They have heavy shells made of calcite. They have a cupped left valve and a flatter right valve, similar to exogyra. As adults, the curvature of the shell could become so pronounced the shell would not be able to open.
Fossil Range Upper Triassic - Eocene.
Mode of Life/Habitat They lived on muddy sea beds, cemented to a small particle of rock. They were infaunal suspension feeders.
Distribution Worldwide (rare in North America but abundant in Europe)
Additional Information They are also known as the "Devil's toe nails" because of their shape (the larger valve is called "the toenail").


Genus Pecten
Pecten.jpg
Additional Information Pecten are a still living genus of scallops that first began to appear during the Cretaceous period. The name pectin comes from the latin word for comb or rake, and the genus was used for the basis of the Shell Oil Company's logo. Like most scallops they have a pair of flat "ears" along the hinge line, and has a series of ridges branching out from the beak. Unlike most bivalves, scallops, including pecten, are mobile creatures, however they are filter feeders and have a diet that consist mostly of plankton.


Genus Glycymeris


Genus Pholadomya
Pholadomya.jpg Pholadomya .jpg
Additional Information Pholadomya is an extinct genus of marine clam that occurred from the early Triassic, to the late Pliocene. It is not on the Official Fossil List in 2020.


Genus Astarte


Genus Nucula

Class Cephalopoda

Order Goniatitida (goniatites)

Order Ceratitida (ceratites)

Order Ammonitida (ammonites)

AM049C.jpg
Additional Information Ammonoids have distinctive suture patterns which fall under three major categories:
  • Goniatitic: These sutures have a zig-zag appearance and are characteristic of Paleozoic ammonoids
  • Ceratitic: These sutures are characterized by lobes and saw-tooth patterns and are characteristic of early Mesozoic ammonoids
  • Ammonitic: These sutures have much more frequent and divided lobes than Ceratitic sutures and they do not have saw-tooth patterns. They are characteristic of late Mesozoic ammonoids


Genus Baculites
Baculites.jpg
Physical Description It was anywhere from 7 cm from 2 meters in size! Males were smaller than females and had lighter ribbing. They had many chambers which would fill with air to increase buoyancy.
Fossil Range Upper Cretceous
Mode of Life/Habitat It was carnivorous and lived in the middle of the water column. There is much debate over whether they lived upright with tentacles on sea bed for foraging for food, or if they lived horizontally and near the surface of the water.
Additional Information It's name means "walking stick rock." It is used as an index fossil.


Genus Dactylioceras
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Additional Information Dactylioceras was an ammonite from the early Jurassic. It probably scavenged on the sea floor. Dactylioceras is a valuable index fossil.


Order Belemnitida (Belemnites)

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Genus Belemnitella
Additional Information Belemnitella is an extinct genus of Cephalopod from the upper Creteaceous. Usually, only the rostrum, or guard, is fossilized.

Order Nautilida (Chambered Nautilus)

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Order Orthocerida ("Orthoceras")

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Additional Information Orthoceras was a cephalopod from the Lower Ordovician to the Upper Triassic, although the time of their extinction is not completely clear. The most likely fed on trilobites and small arthropods.

Class Gastropoda (Snails)


Genus Conus
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Additional Information Conus is a gastropod that ranged from the Eocene to modern day. Conus most notably can fire a toxic harpoon containing various venoms known as conotoxins. They are the only gastropods known to kill humans.


Genus Cypraea
Cypraea.jpg
Additional Information Cypraea, also known as a Cowrie, originated in the Miocene and still lives today. When non-threatened, it is soft. However, when a predator makes contact with it, it hardens its exterior and confuses the predator. They are about 2 cm long. They ate algae and corals. They are widespread throughout North America in distribution. It is sometimes used for jewelry and was used as currency by Africans and Chinese.


Genus Platyceras
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Additional Information Platyceras is a gastrophod ranging from the Silurian to the Middle Triassic. They fed off of crinoid excrement.


Genus Turritella
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Additional Information Turritella is a gastropod that originated in the Late Jurassic and still lives today. The name "Turritella" comes from the latin word turritus which means turreted or towered.


Genus Worthenia
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Additional Information Worthenia was a gastropod that lived from the Devonian to the Triassic. It was named after the paleontologist Amos Henry Worthen.


Echinoderms (Phylum Echinodermata)

Class Asteroidea (Starfish)

Class Blastoidea


Genus Pentremites

Class Crinoidea

Additional Information Competitors are required to identify the stems, columns and calyxes of crinoids for this event.

Class Echinoidea

Additional Information Competitors are required to identify both regular and irregular echinoids, such as sea urchins and sand dollars.

Class Ophiuroidea (brittle stars)