''Mirabilis rotundifolia'' is a species of flowering plant in the

four o'clock family Nyctaginaceae, the four o'clock family, is a family of around 33 genera and 290 species of flowering plants, widely distributed in tropical and subtropical regions, with a few representatives in temperate regions. The family has a unique fruit t ...

known by the common name roundleaf four o'clock. It is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

Colorado Colorado (, other variants) is a state in the Mountain states, Mountain West subregion of the Western United States. It encompasses most of the Southern Rocky Mountains, as well as the northeastern portion of the Colorado Plateau and the wes ...

in the United States, where it is limited to the south-central part of the state.''Mirabilis rotundifolia''.
The Nature Conservancy. It occurs in the

Arkansas River Valley The Arkansas River Valley (usually shortened to River Valley) is a region in Arkansas defined by the Arkansas River in the western part of the state. Generally defined as the area between the Ozark and Ouachita Mountains, the River Valley is cha ...

in Fremont,

Pueblo In the Southwestern United States, Pueblo (capitalized) refers to the Native tribes of Puebloans having fixed-location communities with permanent buildings which also are called pueblos (lowercased). The Spanish explorers of northern New Spain ...

,''Mirabilis rotundifolia''.
Center for Plant Conservation. and Las Animas Counties. This perennial herb has hairy erect or upright stems measuring 20 to 30 centimeters long. The leaves have thick oval or round blades up to 7 centimeters long by 6 wide. The branching

inflorescence An inflorescence is a group or cluster of flowers arranged on a Plant stem, stem that is composed of a main branch or a complicated arrangement of branches. Morphology (biology), Morphologically, it is the modified part of the shoot of sperma ...

has bell-shaped involucres each containing three purple-pink flowers about a centimeter wide.''Mirabilis rotundifolia''.
Flora of North America. The flowers open in the morning and close by mid-morning or mid-day. The hairy fruit is about half a centimeter long. This plant grows on the Smoky Hill Member of the

Niobrara Formation The Niobrara Formation , also called the Niobrara Chalk, is a geologic formation in North America that was deposited between 87 and 82 million years ago during the Coniacian, Santonian, and Campanian stages of the Late Cretaceous. It is com ...

, generally on outcrops of shale. The habitat is mostly barren terrain in shrubland and woodland ecosystems. Associated species include '' Frankenia jamesii''. The main threat to this rare species is residential development. There are 29 occurrences, but only 12 are in good condition.

References

External links

USDA Plants Profile
{{Taxonbar, from=Q4295495 rotundifolia Flora of Colorado