Calvert Cliffs Collecting Location Page: Calvert CLiffs, MD
All fossils that can be found at the Calvert Cliffs of MD
Calvert Cliffs Coffee Club Coffee Cups! A unique gift for the fossil hunter.
Printable Identification Fossil Sheets for Vertebrates and Invertebrates of the Calvert Cliffs
Squalodon Gallery Facts and Information about the Miocene Shark Toothed Whale
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(The smallest divisions in the ruler are 1/8")
Myliobatiformes order (Rays)
Rays are related to Sharks and Skates, as they are all in the Chondrichthyes Class. Fish
in this class have a skeleton made of cartilage instead of true bone. What this means for the
fossil collector is bones from these animals seldom fossilize. Occasionally a vertebra may
be found, however mostly the hard shark teeth and ray crushing plates are found.
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Myliobatidae family (Eagle Rays)
Today, the bay is home to the Cownose Ray
(Rhinoptera bonasus), an Eagle Ray which can get as large as 3 feet in length. If you
are
boating, or snorkeling, you can sometimes catch them basking in the sun near the surface
of the water. Here, we were visited by a large one
while snorkeling
In the Calvert & Choptank Sea, there was a wide array of genus of Eagle Ray in the bay, that
included many tropical forms not found here today.
As a result, identifying
crushing plate fragments commonly found on the beaches are very difficult.
Some of the common genus include Aetobatis (Bonnet Rays),
Aetomylaeus (Smooth-tail Eagle Rays), Myliobatis (Eagle Rays),
and Rhinoptera (cownose rays) which inhabit the bay today.
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Ray crushing plates
Rays have modified teeth that form flat crushing plates. These crushing plates
are adapted for eating mollusks and crustaceans on the sea floor. They suck their prey up
like a vacuum and simply crush them between their upper and lower crushing plates.
Most Ray fossils found are tiny fragments of these crushing plates. These fragments
can sometimes be difficult to identify to a genus level.
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Aetomylaeus sp.
(Smooth-tail Eagle Ray partial crushing plate)
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This plate came from a large species of Aetomylaeus, which was probably
around 6 - 7 feet in width.
Partial crushing plates, like this one, are very difficult to find due to their fragile
nature. Amy found this one still in a big clay pebble, probably from Zone 9. A piece of
the pebble was missing. This missing part contained the rest of the plate! We figure
another collector saw the plate piece in the pebble fragment, and took it without noticing the
rest of the plate in the rest of the pebble.
Here are some pics of it when it was found in the pebble.
The left view is the side that did the crushing, the right is the back side of the plate
Formation: Calvert, Plum Point member, Zone 9
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: South of Brownies Beach, Calvert Co., MD
Size: ~ 3.5 x 2" (88 x 50mm)
Date: Summer 2002
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Aetomylaeus sp.
(Smooth-tail Eagle Ray partial crushing plate)
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This is a partial ray plate
The left view is the side that did the crushing, the right is the back side of the plate
Formation: Calvert
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: Chesapeake Bay Area, VA
Size: ~ 1.5 x 2" (38 x 51mm)
Date:
September, 2010 TRIP
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Aetobatis sp.
(Bonnet Ray partial crushing plates)
Another Ray in the Myliobatidae family commonly found at the cliffs is the Bonnet Rays.
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Imaged here are upper Bonnet Ray plate fragments. They are easy to identify as the
plate elements are "V" shaped. Lower plate fragments are more difficult to identify
as the fragments look closely like Myliobatis sp.
Formation: Calvert, Plum Point member
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: Randle Cliffs, Calvert Co., MD
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Myliobatis sp.
(Eagle Ray Dental Plate fragments)
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These are probably fragments of Eagle Ray dental plates.
Formation: Calvert, Plum Point member
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: Randle Cliffs, Calvert Co., MD
Size: ~ 1" (25mm)
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? sp.
(Ray dermal scute)
Rays have body armor (scutes) under their skin on certain places of their bodies.
The tops of them have what looks like an enamel scale sticking out, while the undersides
look like rock fragments. Since the undersides look just like rock fragments,
they can be difficult to spot.
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This is the top view of a small one. Notice the scale like structure of the scute.
Formation: Calvert, Plum Point member
Age: Early - Middle Miocene ~ 18-15 m.y
Location: Randle Cliffs, Calvert Co., MD
Size: 3/4" (19mm)
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These are fragments of ray tail spines.
Formation: Calvert, Plum Point member
Age: Early - Middle Miocene ~ 18-15 m.y
Location: Randle Cliffs, Calvert Co., MD
Size: usually < 1" (25mm)
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?Acipenser sp.
Sturgeon
Sturgeon dermal plate fragment
Identification based on Purdy et al (2001, p.161).
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I believe this is a tiny fragment of a Sturgeon scute.
For an image of a better scute fragment, look at the scute on the
Lee Creek collection page.
Formation: Calvert, Plum Point member
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: Randle Cliffs, Calvert Co., MD
Size: ~ 1/2" (13mm)
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Megalops cf M. atlanticus
Tarpon
Go to the
Tarpon Fossil Gallery
page for more info about Fossil Tarpon and Identification
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These are seven associated vertebra and a fragment of skull from a Tarpon.
The fourth vertebra was left in matrix for verification of the Calvert Zone.
Formation: Calvert: Zone 14
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: Chesapeake Bay Area
Size: Each vert is ~ 1.5" in diameter (38mm)
Date:
November, 2009 TRIP
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Crocodilia order (Crocodiles)
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Thecachampsa antiqua (Leidy, 1852)
Crocodile tooth
Identification based on Myrick (2001, p.222)
According to Myrick (2001, p.222), since there
is a large variation in tooth shape in Thecachampsa dentitions,
and there are no important morphological differences between the skulls of
crocodiles found in the Chesapeake Group and other tertiary deposits, all the
crocodiles should be assigned to T. antiqua.
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This is one of the best fossil crocodile teeth I've ever seen. Even though it has no root, It's
beautiful. Looks like it came out of the mouth yesterday, even though it is Miocene in age.
Click on the pic to see the trip it was found on.
Formation: Calvert
Age: Middle Miocene ~ 15-12 m.y.
Location: Chesapeake Bay Area
Size: 2 1/2" slant height (54mm)
Date:
April, 2007 TRIP
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This croc tooth is damaged. However, the damage reveals the internal struture of a crocodile tooth.
Formation: Calvert
Age: Middle Miocene ~ 15-12 m.y.
Location: Chesapeake Bay Area
Size: ~ 1" (25mm)
Date:
September, 2010 TRIP
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This is a very worn Croc tooth. The key to identifying it as a croc tooth is the conical cavity at the bottom of the tooth.
A crocodile cavity is different than one from a sperm whale tooth.
Formation: Calvert
Age: Middle Miocene ~ 15-12 m.y.
Location: Chesapeake Bay Area
Size: ~ 1" (25mm)
Date:
September, 2010 TRIP
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This is the most worn Croc tooth I have ever seen,
however, it is a very nice reddish brown color.
Formation: Choptank
Age: Middle Miocene ~ 15-12 m.y.
Location: Matoaka cottages, Calvert Co., MD
Size: ~ 7/8" (23mm)
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Testudine order (Turtles)
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After being misidentified for over a year, I finally realized this is most of
a turtle vertebrae. The first pic is the side that connects to the neural scute, and the last
is a side view, where the rib would attach. I think determining its Genus would be nearly impossible
due to the poor condition of the vert.
Formation: Calvert, Plum Point member
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: Randle Cliffs, Calvert Co., MD
Size: ~1 1/4" by 6/8" (31mm by 18mm)
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Cheloniidae family (Hard-shelled Seaturtles)
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Syllomus aegyptiacus
Carapace of a Hard-shelled Sea Turtle
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Click on the pic for more info/ better pics!
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I found most of a turtle carapace (top of a turtle shell). It is in kinda bad shape, due to the waves beating it up.. It was
found in a chunk of cliffies along the water.
Click on the image for up to date pics, and more information.
Formation: Choptank (zone will be determined shortly)
Age: Middle Miocene ~ 15-12 m.y.
Location: Near Kenwood Beach, Calvert Co., MD
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Pinnipedia order (Seals, Walrus, etc..)
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Phocidae sp.
Seal Cervical Vertebra (C-3 to C-7?)
Identification based on Timmerman (1997, p.18).
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This looks almost identical to a seals' 3
through 7th cervical (neck) vertebrae.
It was found near the base of a cliff partially in clay, with the spinous process
shattered, lying around it. We did our best to piece it together.
Formation: Calvert, Plum Point Member
Age: Early - Middle Miocene ~ 18-15 m.y
Location: Randle Cliffs, Calvert Co., MD
Size: ~3 7/8" by 2" wide (98 by 51 mm)
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Odontocete sub-order
Toothed Whales
(Including Dolphins and Porpoises)
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Squalodon sp. tooth
A Squalodon, or"Shark-toothed whale" was a type of primitive toothed whale
belonging to the extinct Squalodonotidea family
and S. tiedemani. I don't know which species this is.
For more information about Squalodons, please take a look at the
Squalodon Gallery.
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This is probably a worn incisor (tip of tooth,
and bottom of root are missing). Squalodon teeth are very hard to find, and much rarer than shark teeth, as
whales do not constantly loose their teeth like sharks do.
Also, these are less common than the more modern looking Mysteceti, or baleen whales, found here.
Formation: Calvert, Plum Point Member
Age: Early - Middle Miocene ~ 18-15 m.y
Location: Plum Point, Calvert Co., MD
Size: ~ 2 1/4" (57mm)
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Kentriodontidae and Eurhinodelphidae family (extinct Porpoises, Dolphins, etc..)
There were perhaps a dozen or so genus of porpoise in this area in the Miocene. Some of
the common genus includes the
extinct Kentriodon and Eurhinodelphis genus. For more information
about the Eurhinodelphis genus, look at the
additional Eurhinodelphis information in the
Gallery section.
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Dolphin-Porpoise Teeth
Porpoise teeth are much rarer than shark teeth, as porpoises do not continuously loose their teeth.
Also, it is more difficult to spot porpoise teeth, as they tend to roll around in the waves. They
are usually found by sifting in the pebble areas.
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This is a larger than normal porpoise tooth.
Click on the pic to see the trip it was found on
Formation: Calvert
Age: Early - Middle Miocene ~ 18-15 m.y
Location: Chesapeake Bay Area
Size: ~ 1 1/2" (38mm)
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This is a larger than normal porpoise tooth.
Click on the pic to see the trip it was found on
Formation: Calvert
Age: Early - Middle Miocene ~ 18-15 m.y
Location: Chesapeake Bay Area
Size: ~ 1 5/8" (31mm)
Date:
September, 2010 TRIP
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These are some kind of primitive porpoise teeth. There were numerous
species, but I have no clue how to further identify them.
With that said,
the teeth are most likely
from the Kentriodon and/or the
Eurhinodelphis
genus. Both genus have small teeth such as these.
Formation: Calvert, Plum Point Member
Age: Early - Middle Miocene ~ 18-15 m.y
Location: Randle Cliffs, Calvert Co., MD
Size: ~ 5/8" (16mm)
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Porpoise Periotic ear bone
Ear bones are difficult to spot, as they look like pebbles. It takes a trained eye to
spot these.
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These are porpoise inner ear bones. They are often mistaken for rocks, especially
if they are worn such as the ones in the image.
The inner ear bones (the tympanic bulla and periotic) are made from very dense bone, and therefore,
often fossilize.
A porpoise bulla can be seen on the
Lee Creek collection page.
Formation: Calvert, Plum Point Member
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: Willows, Calvert Co., MD
Size: ~ 1/2 to 1" (51mm)
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Porpoise Cervical Vertebra
Identification based on Timmerman (1997, p.18).
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This is a porpoise cervical vertebra. They are easily identifiable
due to the placement of the processes (mostly missing here), and their thinness compared
to other vertebrae.
If you notice, this particular vertebrae has the ephesis fused, which means it is from an adult.
Since it is from an adult, and is relatively small, it probably came from a smaller porpoise genus
such as the Kentriodon genus.
Formation: Calvert, Plum Point Member
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: Willows, Calvert Co., MD
Size: ~ 2" (51mm)
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These are two additional porpoise cervical vertebrae.
I'm not sure what genus these verts are from.
Formation: Calvert, Plum Point Member
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: Plum Pt., Calvert Co., MD
Size: ~ larger one is 3.5" (87mm) including the remaining processes
Date: Summer, 2002
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Complete Porpoise Upper Thoracic Vertebra
Identification based on Timmerman (1997).
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Porpoise Thoracic Vertebra
Kentriodon sp. vertebra
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This appears to be a thoracic vertebra of a small species of Kentriodon porpoise. The
processes are obviously missing.
Formation: Calvert, Plum Point Member
Age: Early - Middle Miocene ~ 18-15 m.y
Location: Willows, Calvert Co., MD
Size: ~1 1/8" (28.5mm)
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Porpoise Misc. Vertebra
Identification based on Timmerman (1997).
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Epiphyses from a Porpoise Vertebra "Cookies"
Identification based on Timmerman (1997, p.4).
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Epiphysis is a part of a bone (usually the end) that ossifies separately from the
bone. The epiphyses also attached to the bone at a later date. So, in a juvenile, the
epiphyses are
usually not yet attached. When a juvenile porpoise or whale dies, the epiphyses often
separate from the bone before fossilization. The detached epiphyses from the vertebrae of
juveniles resemble cookies. The far right vertebra in the "misc vertebra"
picture has its epiphysis missing.
Formation: Calvert, Plum Point Member
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: Randle Cliffs, Calvert Co., MD
Size: ~1 3/8" (34mm) diameter, 1/2" (13mm) thick
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Porpoise Rib... most of one
Identification based on Timmerman (1997).
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This is most of a porpoise rib. It appears to be a rib from the rear of rib cage, or a floating rib. It was dug out of a chunk of freshly fallen
zone 10, however, before I found it,
I smashed the hammer through the center of the rib, thus loosing about 1/2" of the middle of the rib. It is also curved more than this flat image shows.
Notice the small bite marks all over the rib, they are hard to see in this image.
Formation: Calvert, Plum Point Member, Zone 10
Age: Middle Miocene ~ 16-15 m.y.
Location: Randle Cliffs, Calvert Co., MD
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Mysteceti sub-order
(Baleen Whales)
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Cetotherium
Fragment of a squamosal cranial element from a Cetotherium?
(ENGLISH TRANSLATION: Back piece of the skull from an early baleen whale?)
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Click on the pic for more info!
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According to some very qualified people at an MGS meeting, this
is probably a fragment of the squamosal (rear piece of the skull) from possibly a baleen whale (Mysticeti).
It was found while snorkeling for fossils.
Click on the image for more pictures.
Formation: Choptank
Age: Middle Miocene ~ 15-12 m.y.
Location: Matoaka Cottages, Calvert Co., MD
Size: ~ 7" x 7" x 4.5"
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Small bone fragments, such as rib pieces, and
chunks of cartilage are abundant at the cliffs.
These are most likely fragments from
dolphins, whales, and seals
Formation: Calvert, Plum Point Member
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: Randle Cliffs, Calvert Co., MD
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The white line on the side view is a small gash, probably a scrape mark by a small
shark tooth. Also, the puncture marks in the top view may also be from small shark teeth,
as there are smaller punctures on the other side, which may be from the opposite
row of teeth.
Also, look at the porpoise rib in the marine mammals section, it has small bite marks
all over it.
Formation: Calvert, Plum Point Member
Age: Early - Middle Miocene ~ 18-15 m.y.
Location: Randle Cliffs, Calvert Co., MD
Size: ~1.5" (31mm)
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