A View South from Cundick Ridge
A view south from Cundick Ridge located approximately 2 miles as the crow flies north of the visitor center. A one mile walk on a dirt road (vehicles prohibited) gets you here.
Fresh-Water Ray - National Parks Gallery
"Heliobatis radians" is a prehistoric stingray which lived in fresh water lakes during the Eocene. Fossils of "Heliobatis" have been found in rocks within and around Fossil Butte National Monument, Wyoming.
Fossil Butte national monument - Undescribed Millipede
The only millipede fossil found to date in Fossil Lake.
Snow Covered Butte - National Parks Gallery
Winter storms often lay a blanket of snow over the landscape. One storm can dump several feet of snow.
Arches National Park, Ipomopsis aggregata
Common name: scarlet gilia. Family: Polemoniaceae (Phlox Family). Confirmed as present in the following Northern Colorado Plateau Network parks: Arches National Park, Bryce Canyon National Park, Canyonlands Nat... More
Fresh-Water Fish - National Parks Gallery
"Diplomystus dentatsus" is a prehistoric herring like fish. It lived in fresh water lakes during the Eocene Fossils of Diplomystus have been found in rocks within and around Fossil Butte National Monument, Wyoming.
Arches National Park, Eriogonum ovalifolium
Common name: cushion buckwheat. Family: Polygonaceae (buckwheat family). Confirmed as present in the following Northern Colorado Plateau Network parks: Arches National Park, Canyonlands National Park, Capitol R... More
North Slope of Cundick Ridge - Public Domain image, National Parks Gal...
North facing slopes at higher elevation support aspen and and limber pine forests. The aspen leaves are beginning to show their fall colors.
Arches National Park, Ipomopsis aggregata
Common name: scarlet gilia. Family: Polemoniaceae (Phlox Family). Confirmed as present in the following Northern Colorado Plateau Network parks: Arches National Park, Bryce Canyon National Park, Canyonlands Nat... More
Fossil Butte national monument - Dipteronia sp.
This seed is from a plant in the Sapindaceae family. The seed is approximately 1.4 cm across. Catalog number FOBU9987.
Fossil Butte national monument - Fossilized fish
Fossilized fish in Fossil Butte National Monument, Wyoming.
Looking for fossils - National Parks Gallery
GIP Anthony Menicucci (center) opening the scientific fossil quarry and looking for fossils at Fossil Butte National Monument, Wyoming.
Fossil Butte national monument - Examining limestone
Paleontology GIP Anthony Menicucci examining fragments of limestone from the Green River Formation for fossils exposed on the surface in Fossil Butte National Monument, Wyoming.
Fossil Butte national monument - Examining limestone
Anthony Menicucci, Paleontology GIP, lifting a slab of limestone in the research quarry at Fossil Butte National Monument, Wyoming.
Asterotrygon maloneyi, male - National Parks Gallery
The narrow, paired fins at the base of the tail were used to position the female stingray to most effectively fertilize eggs as they were laid. Catalog number FOBU408
Fossil Butte national monument - Junior Ranger
Nicole Reynaud, Paleontology GIP for Fossil Butte National Monument, Wyoming, showing a Junior Ranger fossils in the field.
National parks: Leaf - public domain image
Unidentified leaf from the Fossil Lake deposits in Fossil Butte National Monument, Wyoming.
Fossil Butte national monument - Cardiospermum coloradoensis
This small lobed leaf of a balloon vine occurs in great abundance in the Parachute Creek Member of the Green River Formation deposited by Lake Uinta in what is now Colorado and Utah. Catalog number FOBU10725.
National parks: Leaf - public domain image
Unidentified leaf from the Fossil Lake deposits in Fossil Butte National Monument, Wyoming.
Fossil Butte national monument - Crossopholis magnicaudatus
The predatory fish, Crossopholis magnicaudatus, from the Green River Formation at Fossil Butte National Monument, Wyoming.
Unidentified extinct baenid turtle
Unidentified extinct baenid turtle from the Green River Formation in Fossil Butte National Monument, Wyoming.
Fossil Butte national monument - Gyrocarpus sp.
This came from a tree related to living sassafras trees. Both trees produce leaves in three shapes, unlobed, two lobed like this one, and three lobed. The leaf is 41.9 cm. Catalog number FOBU10668.
inidentified leaf, approximately 5 cm long
Fossilized plants are often difficult to identify because their parts, stem, roots, leaves, and fruiting structures are often not attached.
Fossil Butte national monument - unidentified flower
The detailed preservation of this flower is due, in part, to the fine-grained nature of the limestone matrix it is found in.
unidentified member of the Trionychidae family
This 1.7 meter (5 foot 6 inch) softshell turtle is one of the largest turtles from Fossil Lake. During the Eocene, trionychid turtles reached maximum size. Today, North America's largest softshell turtles reach... More
unidentified insect of the order Hemiptera
Collectively known as true bugs, Hemiptera species include cicadas, aphids, planthoppers, leafhoppers, shield bugs and others. (fossil is approximately 1 cm long)
beetle of the family Buprestidae, 3.5 cm long
Because of their glossy irridescent colors, members of the family Buprestidae are known as jewel beetles or metallic wood-boring beetles, such as the emerald ash borer.
unidentified insect, approximately 1 cm long
Preserved insects from Fossil Lake sometimes show color patterns, wing venation, and sex related characteristics. Note the pattern on the wings of this fossil insect.
Knightia eocaena, approximately 11 cm long
Knightia eocaena is perhaps the most common complete vetebrate fossil in the world. It is Wyoming's state fossil.
Fossil Butte national monument - unidentified flower
Fossilized plants are more difficult to identify than living plants because their parts often become separated before they are preserved. The plant that produced this flower may be impossible to identify becaus... More
unidentified beetle, approximately 4.5 cm long
Beetles are the most diverse and abundant group of animals today but are poorly represented as fossils in Fossil Lake.
unidentified leaf, approximately 15 cm long
Two hundred and seventy six leaves, seeds and flowers are known from the Fossil Lake deposits. Fossil plants are key in determining the climate of past environments.
unidentified leaf, approximately 8 cm long
Over 300 fossil plants have been discovered in the Fossil Lake deposits.
unidentified fly, approximately 1 cm long
The insect fossils from Fossil Lake sometimes show color patterns, wing venation, and sex-related characteristics. Notice the venation pattern on the wings of this fly.
unidentified leaf, approximately 3 cm long
Plants are key to understanding past climates. If a population of 25 or more different shaped leaves are collected from a locality, paleontologists use a technique called leaf-margin analysis to estimate temper... More
unidentified baenid turtle - National Parks Gallery
This ten-inch-long turtle belongs to the Baenidae family, an extinct North American group. Shell characteristics, a very long tail and recurved claws suggest they were strong bottom walking turtles.
Mass mortality of Knightia eocaena
Knightia eocaena was a schooling fish. This specimen is from the sandwich beds where several mortality beds of adult fish are found. (fish are approximately 10 cm long)
Palmites sp., approximately 2 meters long
The presence of palm fossils indicate a much warmer and wetter climate 52 million years ago, similar to the Gulf coast states today.
Diplomystus dentatus with Knightia in its mouth
This fossil fish was not found in a mass mortality (beds that contain hundreds of fish on one surface) suggesting it did not die in a catastrophe. It most likely died from starvation or suffocation because it c... More
Cockerellites liops, approximately 13 cm long
Cockerellites liops (formerly Priscacara liops) occurs in at least one mass mortality layer indicating it was a schooling fish.
unidentified insect of the order Hemiptera, 1.5 cm
Preserved insects from Fossil Lake sometimes show color patterns, wing venation, and sex related characteristics. Note the pattern around the edge of this true bug's abdomen.
Knightia alta, approximately 12.5 cm long
In Fossil Lake, the deep-bodied Knightia alta is less common that Knightia eocaena.
Mioplosus labracoides, approximately 9 cm long
The mouth of Mioplosus, an extinct perch-like fish, was lined with numerous tiny sharp teeth. This aided in grasping prey, but also prevented them from expelling fish too big to injest.
Phareodus encaustus, 50 cm long
Large teeth and rear-placed fins make Phareodus encaustus well suited for catching and eating other fish.
Crossopholis magnicaudatus, approximately 1 m long
Unlike its filter-feeding modern North American relative, Crossopholis was a predatory fish.
Fossil Butte national monument - Protorohippus sp.
Most mammal fossils consist of teeth and bone fragments. This fully-articulated early horse is an extremely rare find and to date, the first of two horses found in the Green River Formation.
Heliobatus radians, approximately 30 cm long
Heliobatus radians had small teeth for crushing snails and other mollusks and barbed spines on the tail for defense.
Procambarus primaevus, approximately 5 cm long
Crayfish lived in the shallow, near-shore water of Fossil Lake. Procambarus is known only from the Eocene deposits of Fossil Lake. Its closest living relative, Austrocambarus, is found in Mexico.
Onychonycteris finneyi (cast) - National Parks Gallery
The fossils of the Green River Formation's ancient Fossil Lake are remarkable for the broad spectrum of species found here. This 5.5 inch long bat is the most primitive bat known. Claws on each finger of its wi... More
Fossil Butte national monument - GeoCorps interns
GeoCorps intern, Taormina Lepore, is helping a young visitor split open a rock at the Fossil Butte National Monument, Wyoming, research quarry.
Fossil Butte national monument - Cleaning fossils
GIP Julie Rozen cleaning fossils with a Junior Ranger at Fossil Butte National Monument, Wyoming.
Tourist Attraction - Fossils on the Ridge
Freeze/thaw action fractures rock revealing the fossils. Picryl description: Public domain photograph of National Park, nature, free to use, no copyright restrictions image.
Visitor Center in Snow-Covered Landscape
Up to two feet of snow is on the ground November - March.
Cleaning a fossil - National Parks Gallery
Here Megan Ferre (Paleontology GIP) is cleaning an exploded fish fossil at the visitor’s center during a demonstration for visitors at Fossil Butte National Monument, Wyoming.
Looking for fossils - National Parks Gallery
Megan Ferre (Paleontology GIP) searches for fossils at the Fossil Butte National Monument, Wyoming, research quarry.
Fossil Butte national monument - Paleontology GIP
Paleontology GIP, Megan Ferre, pointing out a fossilized fish tail in the visitor’s center at Fossil Butte National Monument, Wyoming.
Megan Ferre, GIP intern - Public Domain image, National Parks Gallery
Megan Ferre, GIP intern cleans an exploded fish fossil at Fossil Butte National Monument, Wyoming.
Double Rainbow On Fossil Butte - Public Domain image, National Parks G...
Thunderstorms bring rain and colorful rainbows. Picryl description: Public domain photograph of National Park, nature, free to use, no copyright restrictions image.
A View of Fossil Basin from Cundick Ridge
Ancient Fossil Lake deposits are visible in the distance. Picryl description: Public domain photograph of National Park, nature, free to use, no copyright restrictions image.
Fossil Butte national monument - Fossil Butte
Fossil Butte is capped by limestone deposited by ancient Fossil Lake, part of the famous Green River Formation. Sagebrush steppe vegetation dominates the landscape of Fossil Butte National Monument.
Fossil Butte national monument - Exploded gar
A fossilized exploded gar (fish) being prepared in the lab by GIP Taryn O'Connell (Fossil Butte National Monument, Wyoming).
Exhibit at Fossil Butte National Monument
Exhibit at Fossil Butte National Monument, Wyoming, about fossilization that Guest Scientist Taryn O'Connell assisted with.
Amanda Meacham, GIP intern - Public Domain image, National Parks Galle...
Amanda Meacham, GIP intern preparing fossil fish at Fossil Butte National Monument, Wyoming.
Mitchell Hermann, GIP intern - Public domain natural history illustrat...
Mitchell Hermann, GIP intern excavating fossils at Fossil Butte National Monument, Wyoming.
Green River Formation fossil, Fossil Butte National Monument, 2016.
The presence of palm fossils indicate a much warmer and wetter climate, similar to today's gulf coast region, occurred 52-million yeasr ago. Palmitates sp. Specimen approximately 2-meters long.
Mass Mortality of Cockerellites liops
For number, variety, and detail of fossil fish, few places equal ancient Fossil Lake of the Green River Formation. Mass mortalities such as this one are uncommon. These multiple deaths may have been caused by t... More
Green River Formation fossil, Fossil Butte National Monument, 2016.
Cockerellites liops (formerly Priscacara liops) occurs in at least one mass mortality layer, indicating that it was a schooling fish. Specimen approximately 13-cm long.
Fossil Butte national monument - Cockerellites liops
Ancient Fossil Lake of the Green River Formation is known for excellent preservation, abundance and diversity of life. This mass mortality of fossil fish is just one example.
Green River Formation fossil, Fossil Butte National Monument, 2016.
In Fossil Lake, this deep-bodied Knightia alta is less common than Knightia eocaena. Knightia alta specimen approximately 12.5-cm long.
Green River Formation fossil, Fossil Butte National Monument, 2016.
Fossilized plants are much more difficult to identify than living plants because their delicate parts often become separated before they are preserved. The plant that produced this flower may be impossible to i... More
Green River Formation fossil, Fossil Butte National Monument, 2016.
Large teeth and rear-placed fins make Phareodus encaustus well-suited for catching and eating other fish. Specimen approximately 50-cm long.
Green River Formation fossil, Fossil Butte National Monument, 2016.
Fossilized plants are much more difficult to identify than living plants because their delicate parts often become separated before they are preserved. The detailed preservation of this unidentified flower is d... More
Green River Formation fossil replica, Fossil Butte National Monument, ...
A broad range of species can be found in the Green River Formation's ancient fossil lake. This 5.5-inch long bat is the most primitive bad known to science. Claws on each finger of its wings indicate that it wa... More
Green River Formation fossil, Fossil Butte National Monument, 2016.
The mouth of Mioplosus was lined with numerous tiny sharp teeth useful for grasping prey but, as evidenced from this specimen, also prevented unfortunate Mioplosus from expelling fish that were too large for it... More
A snake that is laying down on the ground. Fossil hose petrified.
Stock photo: A fossil of a snake, found in the mountains of the south china sea / A snake that is laying down on the ground.
Green River Formation fossil, Fossil Butte National Monument, 2016.
Crayfish lived in the shallow, near-shore water of Fossil Lake and are known only from Eocene lake deposits. The closest living relative of Procambarus is Austrocambarus, found in Mexico. This Procambarus prima... More
Zion National Park, Symphoricarpos oreophilus
Common name: mountain snowberry. Family: Caprifoliaceae (honeysuckle family). Confirmed as present in the following Northern Colorado Plateau Network parks: Black Canyon of the Gunnison National Park, Bryce Can... More
Comandra umbellata var. pallida
Common name: bastard toadflax. Family: Santalaceae (sandalwood family). Confirmed as present in the following Northern Colorado Plateau Network parks: Arches National Park, Black Canyon of the Gunnison National... More
Fossil Butte national monument - Ancestral Bat
"Icaronycterix index" is a very early bat that lived during the Eocene. Fossils of "Icaronycterix" have been found near Fossil Butte National Monument, Wyoming.
Arches National Park, Oenothera caespitosa
Common name: tufted evening primrose. Family: Onagraceae (evening primrose family). Confirmed as present in the following Northern Colorado Plateau Network parks: Arches National Park, Bryce Canyon National Par... More
Comandra umbellata var. pallida
Common name: bastard toadflax. Family: Santalaceae (sandalwood family). Confirmed as present in the following Northern Colorado Plateau Network parks: Arches National Park, Black Canyon of the Gunnison National... More
Arches National Park, Eriogonum ovalifolium
Common name: cushion buckwheat. Family: Polygonaceae (buckwheat family). Confirmed as present in the following Northern Colorado Plateau Network parks: Arches National Park, Canyonlands National Park, Capitol R... More
Arches National Park, Oenothera caespitosa
Common name: tufted evening primrose. Family: Onagraceae (evening primrose family). Confirmed as present in the following Northern Colorado Plateau Network parks: Arches National Park, Bryce Canyon National Par... More
Arches National Park, Streptanthus cordatus
Common name: heartleaf twistflower. Family: Brassicaceae (mustard family). Confirmed as present in the following Northern Colorado Plateau Network parks: Arches National Park, Bryce Canyon National Park, Canyon... More
Cleaning fossils (25472839792)
GIP Julie Rozen cleaning fossils with a Junior Ranger at Fossil Butte National Monument, Wyoming. (NPS Photo by Julie Rozen, GIP)ulie Rozen, GIP)
A hike up a steep spur trail will bring you to the historic quarry whe...
A tan hill with little vegetation. Wooden stairs make their way halfway up the hill and then over to the right. The sky is covered with diffused clouds. A hike up a steep spur trail will bring you to the histo... More
An azolla fragment that is approximately 2 cm long. Catalog number FOB...
A black plant fossil with feathery edges. The rock directly surrounding the fossil is an orange and further away it is variegated tan and brown. An azolla fragment that is approximately 2 cm long. Catalog numb... More
Bowen, Robert- fossil bee (a14604a6-9d80-4841-862a-c9cef8f6fc93)
A side view of a fossil bee. The wing with veins and the legs are easily visible. A fossil bee. Catalog number FOBU17605.
Cliffs of Fossil Butte (d8de2cbc-1b8d-4b29-9f41-a33ef5409e88)
Cliffs rise straight up from a steeply sloping hillside covered in trees and bushes. Cliffs along the ridge known as Fossil Butte.
Fossil hunter David Haddenham's simple a-frame cabin is located along ...
A worn-down wooden a-frame cabin amid sagebrush with a rocky cliff behind. Fossil hunter David Haddenham's simple a-frame cabin is located along the Historic Quarry Trail. Haddenham lived in this cabin while q... More
Fossil Butte Member Type Section (c8e069d5-7ca0-4363-ad59-e0c9a20bae3d...
A craggy cliff face with a steeply sloping hill below. A type section is the best exposure of rocks in that unit. Formations and members are named after geographic place names. In this case, Fossil Butte Membe... More
Historic Quarry Trail View from the Top (81eeb6aa-2e44-4180-8334-cdeed...
Looking across a valley filled with green bushes and shrubs. A trail cuts across from the bottom right diagonally but gets lost in the greenery. A path of stairs is visible immediately to the left in the foreg... More
Lindgren Fossils LLC- insect fossil (0e14f7e3-2e9c-4253-95a9-2e31a9d80...
A beetle fossil with part separated to the left of the body. A fossil insect that is approximately 19.7 mm long. Catalog number FOBU14049.
Lindgren, David- fossil plant (73b6c36a-4820-423a-99f7-3d545972ec60)
A tan stone with a darker shade of tan fossil. The fossil has a central stem with a bunch of thin lines radiating from it at all angles. The edge of the rock is visible at the top right corner. Fossil plant ap... More
Lindgren, David- one vertebrate and two ribs (564547ef-8915-489d-aecb-...
A vertebrate with two ribs sticking up. Thinner skeletal parts than the ribs angle down from the vertebrate. One vertebrate and two ribs. The ribs are approximately 1.75 cm long. Catalog number FOBU11185.
Lindgren, David- two coprolites (09f11f64-bc0e-4475-b59e-9c4d6607eb21)
Two splotchy circles one on the upper left corner the other on the bottom right corner which is cut through by a crack that goes from the bottom of the rock to the top right corner. Two coprolites. Upper copro... More
Lindgren, Thomas- cicada fossil (2a69d1f5-f378-44d3-9956-5ddaa2b13b48)
A fossil insect with head and thorax clearly defined and two lines of its wings out to the sides of the thorax. A fossil cicada that is approximately 6.7 cm long. Catalog number FOBU17462.
Lindgren Fossils LLC- winged seed (850110cc-0082-455d-831b-3ae345306eb...
A winged seed with the lower of the wings mostly missing. The veins of the upper wing are visible and the seed is a dark brown. A winged seed, the wing of which is approximately 4.1 cm long. Catalog number FOBU14023.
Lindgren, Adam- Knightia eoceana cut by swim trace (34349db8-35af-40d0...
A fossil fish separated at the head by a wide, arcing trace. A Knightia eoceana cut in two by a swim trace. The Knightia is approximately 8.5 cm long. Catalog number FOBU17494.
Lindgren, Anthony- partial Notogoneus osculus head (70a5c6be-749d-435d...
Two rocks. The one on the left has a teardrop shaped mottled fossil. The one on the right is similarly shaped but about twice the size. A partial Notogoneus osculus head. The rock on the left is approximately ... More