Chelone is a genus of four species of perennial

Perennial plant

A perennial plant or simply perennial is a plant that lives for more than two years. The term is often used to differentiate a plant from shorter lived annuals and biennials. The term is sometimes misused by commercial gardeners or horticulturalists to describe only herbaceous perennials...

 herbaceous plant

Herbaceous plant

A herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level. They have no persistent woody stem above ground...

s native to eastern North America. They all have similarly shaped flowers (which lead to the name turtlehead due to their resemblance to the head of a turtle), which vary in color from white to red, purple or pink. C. cuthbertii, C. glabra, and C. lyonii are diploid and C. obliqua is either tetraploid or hexaploid.

Relationships to other plants

The closest relatives of Chelone are Chionophila and Nothochelone

Nothochelone

Nothochelone is a monotypic genus of flowering plants in the plantain family containing the single species Nothochelone nemorosa, which is known by the common name woodland beardtongue...

from western North America. It is also more closely related to Collinsia

Collinsia

Collinsia is a genus of about 25 species of annual flowering plants, consisting of the Blue-eyed Marys and the Chinese Houses. It was traditionally placed in the snapdragon family Scrophulariaceae, but following recent research in molecular genetics, it has now been placed in a much enlarged...

than to other members of the family such as snapdragon

Antirrhinum

Antirrhinum is a genus of plants commonly known as snapdragons from the flowers' fancied resemblance to the face of a dragon that opens and closes its mouth when laterally squeezed...

s, plantains

Plantago

Plantago is a genus of about 200 species of small, inconspicuous plants commonly called plantains. They share this name with the very dissimilar plantain, a kind of banana. Most are herbaceous plants, though a few are subshrubs growing to 60 cm tall. The leaves are sessile, but have a narrow...

, and foxglove

Digitalis

Digitalis is a genus of about 20 species of herbaceous perennials, shrubs, and biennials that are commonly called foxgloves. This genus was traditionally placed in the figwort family Scrophulariaceae, but recent reviews of phylogenetic research have placed it in the much enlarged family...

.

Species

C. glabra

Chelone glabra

Chelone glabra is a plant in the family Plantaginaceae .-Description:Chelone glabra is a herbaceous plant found in wetlands and riparian forests of eastern North America with opposite, simple leaves, on stout, upright stems. The flowers are white, borne in late summer and early fall...

is the most widely distributed species of the genus: from Georgia

Georgia (U.S. state)

Georgia is a state located in the southeastern United States. It was established in 1732, the last of the original Thirteen Colonies. The state is named after King George II of Great Britain. Georgia was the fourth state to ratify the United States Constitution, on January 2, 1788...

 to Newfoundland and from Mississippi

Mississippi

Mississippi is a U.S. state located in the Southern United States. Jackson is the state capital and largest city. The name of the state derives from the Mississippi River, which flows along its western boundary, whose name comes from the Ojibwe word misi-ziibi...

 to Manitoba

Manitoba

Manitoba is a Canadian prairie province with an area of . The province has over 110,000 lakes and has a largely continental climate because of its flat topography. Agriculture, mostly concentrated in the fertile southern and western parts of the province, is vital to the province's economy; other...

; the other three are found in more restricted areas.

C. lyonii is found in the Blue Ridge

Blue Ridge Mountains

The Blue Ridge Mountains are a physiographic province of the larger Appalachian Mountains range. This province consists of northern and southern physiographic regions, which divide near the Roanoke River gap. The mountain range is located in the eastern United States, starting at its southern-most...

 of Tennessee

Tennessee

Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...

, North Carolina

North Carolina

North Carolina is a state located in the southeastern United States. The state borders South Carolina and Georgia to the south, Tennessee to the west and Virginia to the north. North Carolina contains 100 counties. Its capital is Raleigh, and its largest city is Charlotte...

, and South Carolina

South Carolina

South Carolina is a state in the Deep South of the United States that borders Georgia to the south, North Carolina to the north, and the Atlantic Ocean to the east. Originally part of the Province of Carolina, the Province of South Carolina was one of the 13 colonies that declared independence...

.

C. cuthbertii is found in two areas: the Blue Ridge of North Carolina and the coastal plain

Atlantic Coastal Plain

The Atlantic coastal plain has both low elevation and low relief, but it is also a relatively flat landform extending from the New York Bight southward to a Georgia/Florida section of the Eastern Continental Divide, which demarcates the plain from the ACF River Basin in the Gulf Coastal Plain to...

 of Virginia

Virginia

The Commonwealth of Virginia , is a U.S. state on the Atlantic Coast of the Southern United States. Virginia is nicknamed the "Old Dominion" and sometimes the "Mother of Presidents" after the eight U.S. presidents born there...

.

C. obliqua is found as tetraploids in the Blue Ridge, or hexaploids in two areas: Tennessee

Tennessee

Tennessee is a U.S. state located in the Southeastern United States. It has a population of 6,346,105, making it the nation's 17th-largest state by population, and covers , making it the 36th-largest by total land area...

 to Arkansas

Arkansas

Arkansas is a state located in the southern region of the United States. Its name is an Algonquian name of the Quapaw Indians. Arkansas shares borders with six states , and its eastern border is largely defined by the Mississippi River...

 and Michigan

Michigan

Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake"....

, or the Atlantic coastal plain

Atlantic Coastal Plain

The Atlantic coastal plain has both low elevation and low relief, but it is also a relatively flat landform extending from the New York Bight southward to a Georgia/Florida section of the Eastern Continental Divide, which demarcates the plain from the ACF River Basin in the Gulf Coastal Plain to...

 from South Carolina

South Carolina

South Carolina is a state in the Deep South of the United States that borders Georgia to the south, North Carolina to the north, and the Atlantic Ocean to the east. Originally part of the Province of Carolina, the Province of South Carolina was one of the 13 colonies that declared independence...

 to Maryland

Maryland

Maryland is a U.S. state located in the Mid Atlantic region of the United States, bordering Virginia, West Virginia, and the District of Columbia to its south and west; Pennsylvania to its north; and Delaware to its east...

.

The relationship between the different populations is complicated and it appears that C. obliqua in fact has arisen several times from diploid ancestors of the other three species. The four species seem to have diverged recently.