Hawthorn Group
Introduction Location of the Hawthorn Group within Florida (in red).The '''Hawthorn Group''' is a stratigraphic unit that includes several geologic formations of Late Oligocene to Pliocene age in North Florida, United States. It is known for its phosphate rock resources, and for its rich assemblages of Neogene vertebrate fossils. It was originally called the Waldo Formation by L.C. Johnson of the United States Geological Survey in 1887, and later became the Hawthorne Group named for Hawthorne, Florida, where its phosphate-rich rock was quarried and processed for use as fertilizer.
Age '''Period''': Neogene'''Epoch''': Miocene'''Faunal stage''': Chattian through early Blancan ~28.4 to ~2.588 mya, a period of
Location The Hawthorn Group extends from Suwannee County in the north and southward to Hernando County. It encompasses in part the counties of Gilchrist, Levy, Dixie, Citrus, Sumter, Alachua and Marion County. The Hawthorn is also present below undifferentiated sediments (TQu) as well as the Tamiami Formation from Polk County south through Highlands, Glades, Hendry, Dade, Collier, and Monroe County at depths ranging from mean sea level near Polk to below 600 meters in Monroe Co. The Hawthorn overlies Ocala Limestone
Sub-units *Arcadia Formation*Coosawhatchie Formation (Miocene-Pliocene)*Peace River Formation (Miocene-Pliocene)*Statenville Formation (Miocene)*Torreya Formation (Miocene)
Paleofauna '''Reptiles'''*''Apalone ferox'' (Florida Softshell Turtle)*''Pseudemys caelata'' (Pond Turtle)*''Terrapene'' (Box Turtle)*''Deirochelys'' (Chicken Turtle)*''Geochelone'' (Tortoise)*''Alligator mississippiensis'' (American Alligator)*†''Gavialosuchus americanus'' or ''Thecachampsa antiqua'' (American Crocodile)*''Typhlops'' (Blind snake)*''Xenodontinae'' (Mud Snake)*''Heterodon'' (Hognose Snake)*''Elaphe'' (Rat Snake)*''Lampropeltis getulus'' (Kingsnake)*''Nerodia'' (Water snake)*''Thamnophis'' (Garter Snake) 	*''Crotalinae'' (Lancehead, Rattlesnake)*''Sistrurus'' (Rattlesnake)'''Birds'''*''Anserinae'' (Swan)*''Podicipedidae'' (Grebe)*''Phalacrocoracidae'' (Cormorant)*''Anhinga grandis'' (Snakebird)*''Ciconiidae'' (Stork)*''Phoenicopteridae'' (Flamingo)*''Ardea'' (Heron)*''Egretta'' (Egret)*''Ardeola'' (Heron)*''Aramidae'' (Limpkin)*''Gruidae'' (Crane-like)*''Rallidae'' (Crakes & Coots)*''Cathartidae'' (New World Vulture)*''Pandionidae'' (Osprey)*''Accipitridae'' (Eagle)*''Passeriformes'' (Songbird)'''Mammals'''*†''Metaxytherium floridanum'' (Sea Cow)*†''Gomphotherium'' (Elephant)*†''Tapirus simpsoni'' (Tapir)*†''Teleoceras proterum'' (Rhinoceros)*†''Aphelops malacorhinus'' (Rhinoceros)*†''Pseudhipparion skinneri'' (Horse)*†''Hipparion tehonense'' (Horse)*†''Neohipparion trampasense'' (Horse)*†''Nannippus westoni'' (Horse)*†''Hippotherium ingenuum'' and ''H. plicatile'' (Horse)*†''Calippus cerasinus'' and ''C. elachistus'' (Horse)*†''Protohippus gidleyi'' (Horse)*''Microchiroptera'' (Microbat)*†''Leptarctus'' (Mustelidae)*†''Hoplictis'' (Mustelidae)*†''Plionictis'' (Mustelidae)*†''Sthenictis lacota'' (Mustelidae)*†''Arctonasua floridana'' (Raccoon)*†''Paranasua biradica''*†''Leptocyon''*†''Epicyon haydeni'' and ''E. saevus'' (Proto-dog)*†''Nimravides galiani'' (False Saber-tooth cat)*†''Barbourofelis loveorum'' (False Saber-tooth cat)*†''Antilocaprinae'' (Antilope)*†''Pseudoceras'' (Early horse-type ungulate)*†''Yumaceras hamiltoni'' (Camel-like)*†''Cetacea'' (Whale)*†''Aepycamelus major'' (Camel)*†''Procamelus grandis'' (Camel)*†''Hemiauchenia minima'' (Camel)*''Talpidae'' (Mole)*''Soricidae'' (Shrew)*†''Archaeolaginae (Rabbit)*''Sciuridae'' (Squirrel)*†''Eucastor planus'' (Beaver)*''Abelmoschomys simpsoni'' (Vole)*†''Mylagaulus elassos'' (Horned gopher)
References * USGS: Florida Geology* Paleobiology database: Love Bone Bed Collection