''Physaria bellii'' is a species of flowering plant in the family

Brassicaceae Brassicaceae () or (the older) Cruciferae () is a medium-sized and economically important family of flowering plants commonly known as the mustards, the crucifers, or the cabbage family. Most are herbaceous plants, while some are shrubs. The le ...

known by the common names Bell's twinpod and Front Range twinpod. 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 elsew ...

Colorado Colorado (, other variants) is a state in the 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 western edge of t ...

in the United States.''Physaria bellii''.
The Nature Conservancy.''Physaria bellii''.
Center for Plant Conservation. This perennial herb produces decumbent or prostrate stems from a

caudex A caudex (plural: caudices) of a plant is a stem, but the term is also used to mean a rootstock and particularly a basal stem structure from which new growth arises.pages 456 and 695 In the strict sense of the term, meaning a stem, "caudex" is m ...

. The plant is covered in hairs, making it silvery. The basal leaves are toothed and the leaves along the stems are smooth on the edges. The

inflorescence An inflorescence is a group or cluster of flowers arranged on a stem that is composed of a main branch or a complicated arrangement of branches. Morphologically, it is the modified part of the shoot of seed plants where flowers are formed o ...

is a

raceme A raceme ( or ) or racemoid is an unbranched, indeterminate type of inflorescence bearing flowers having short floral stalks along the shoots that bear the flowers. The oldest flowers grow close to the base and new flowers are produced as the s ...

of flowers with yellow petals and yellowish

sepal A sepal () is a part of the flower of angiosperms (flowering plants). Usually green, sepals typically function as protection for the flower in bud, and often as support for the petals when in bloom., p. 106 The term ''sepalum'' was coined b ...

s. The fruit is a leathery pod reaching nearly a centimeter in length.''Physaria bellii''.
Flora of North America. Flowering occurs in May and June. This plant grows on the

Front Range The Front Range is a mountain range of the Southern Rocky Mountains of North America located in the central portion of the U.S. State of Colorado, and southeastern portion of the U.S. State of Wyoming. It is the first mountain range encountere ...

in Colorado. It grows on the Niobrara,

Pierre Pierre is a masculine given name. It is a French form of the name Peter. Pierre originally meant "rock" or "stone" in French (derived from the Greek word πέτρος (''petros'') meaning "stone, rock", via Latin "petra"). It is a translation ...

Fountain A fountain, from the Latin "fons" (genitive "fontis"), meaning source or Spring (hydrology), spring, is a decorative reservoir used for discharging water. It is also a structure that jets water into the air for a decorative or dramatic effect. ...

, Ingleside, and

Lykins Formation Lykins is a surname. Notable people with the surname include: *Johnston Lykins Johnston Lykins (April 15, 1800 – August 15, 1876) was a prominent settler and civic leader in the Americans, American American frontier, frontier Town of Kansas, ...

s. The soils are

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

, limestone

shale Shale is a fine-grained, clastic sedimentary rock formed from mud that is a mix of flakes of clay minerals (hydrous aluminium phyllosilicates, e.g. kaolin, Al2 Si2 O5( OH)4) and tiny fragments (silt-sized particles) of other minerals, especial ...

, or red

sandstone Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks. Most sandstone is composed of quartz or feldspar (both silicates) ...

. The habitat is shrubland dominated by ''

Rhus trilobata ''Rhus trilobata'' is a shrub in the sumac genus (''Rhus'') with the common names skunkbush sumac, sourberry, skunkbush, and three-leaf sumac. It is native to the western half of Canada and the Western United States, from the Great Plains to Ca ...

'' and ''

Cercocarpus montanus ''Cercocarpus montanus'' is a North American species of shrub or small tree in the family Rosaceae native to northern Mexico and the western United States. It is known by the common names alder-leaf mountain-mahogany, alder-leaf cercocarpus, and ...

''. The plant is rare in general but locally abundant.Kothera, L., et al. (2007)
Genetic diversity and structure in the rare Colorado endemic plant ''Physaria bellii'' Mulligan (Brassicaceae).
''Conservation Genetics'' 8(5) 1043-50. Potential threats to the species include

hybridization Hybridization (or hybridisation) may refer to: *Hybridization (biology), the process of combining different varieties of organisms to create a hybrid *Orbital hybridization, in chemistry, the mixing of atomic orbitals into new hybrid orbitals *Nu ...

with '' Physaria vitulifera'', a more widespread plant,Kothera, L., et al. (2007)
Assessing the threat from hybridization to the rare endemic ''Physaria bellii'' Mulligan (Brassicaceae).
''Biological Conservation'' 140 110-18. limestone mining, road construction and maintenance, and

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there ...

of plants. The main threat is residential development.

References

External links

USDA Plants Profile for ''Physaria bellii''
{{Taxonbar, from=Q7189511 bellii Flora of Colorado Flora of the Rocky Mountains Endemic flora of the United States Endangered flora of the United States