''Dakotanthus cordiformis'' is an extinct species of flowering plant from the

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...

Western Interior Seaway The Western Interior Seaway (also called the Cretaceous Seaway, the Niobraran Sea, the North American Inland Sea, and the Western Interior Sea) was a large inland sea that split the continent of North America into two landmasses. The ancient sea, ...

of North America.

History

Five-chambered fruit from the Cretaceous

Dakota Sandstone The Dakota is a sedimentary rock, sedimentary geologic unit name of Formation (stratigraphy), formation and Group (stratigraphy), group rank in Midwestern North America. The Dakota units are generally composed of sandstones, mudstones, clays, and ...

were monographed as early as 1874 by

Leo Lesquereux Charles Léo Lesquereux (November 18, 1806 – October 25, 1889) was a Swiss-born bryologist and a pioneer of American paleobotany who studied the formation of peat bogs. Career Lesquereux was born in the town of Fleurier, located in the can ...

for the

United States Geological Survey The United States Geological Survey (USGS), formerly simply known as the Geological Survey, is a scientific agency of the United States government. The scientists of the USGS study the landscape of the United States, its natural resources, ...

. In 1892, Lesquereux published one such fossil as ''Carpites cordiformis''. James Basinger and David Dilcher (1984) re-examined flower fossils from the Dakota Formation in

Nebraska Nebraska () is a state in the Midwestern region of the United States. It is bordered by South Dakota to the north; Iowa to the east and Missouri to the southeast, both across the Missouri River; Kansas to the south; Colorado to the southwe ...

and published them as the "Rose Creek flower", one of the earliest recorded bisexual flowers, after the Rose Creek Pit of the Dakota Formation. In 2018, "Rose Creek flower specimens" were again re-examined and renamed ''Dakotanthus cordiformis'' with a noted similarity to the extant family

Quillajaceae Quillajaceae is a family of flowering plants. It contains only two extant species, '' Quillaja brasiliensis'' and ''Quillaja saponaria ''Quillaja saponaria'', the soap bark tree or soapbark, is an evergreen tree in the family Quillajaceae, ...

References

Cretaceous life of North America Cretaceous plants Cenomanian life Fabales genera Quillajaceae Prehistoric angiosperms {{cretaceous-plant-stub