Microsteris

Microsteris
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Asterids
Order:	Ericales
Family:	Polemoniaceae
Genus:	Microsteris Greene
Species:	M. gracilis
Binomial name
Microsteris gracilis (Hook.) Greene
Varieties
M. g. var. gracilis M. g. var. humilior
Synonyms
List Myotoca Griseb. Collomia bellidifolia Douglas ex Hook. Collomia chubutensis Speg. Collomia eritrichoides Griseb. Collomia gracilis (Hook.) Douglas ex Benth. Collomia gracilis var. andicola Benth. Collomia gracilis var. congesta Wedd. Collomia gracilis var. eritrichoides (Griseb.) Brand Collomia gracilis var. humilior Hook. Collomia gracilis var. minuartioides Franch. Collomia humilis Douglas ex Hook. Collomia micrantha Kellogg Eutoca gracilis Griseb. ex Brand Gilia gracilis Hook. Gilia gracilis Phil. Gilia gracilis subvar. angustifolia Brand Gilia gracilis subvar. bellidifolia Brand Gilia gracilis subvar. californica Brand Gilia gracilis var. congesta (Wedd.) Borsini Gilia gracilis subvar. congesta (Wedd.) Brand Gilia gracilis var. elatior Suksd. Gilia gracilis var. eritrichoides Brand Gilia gracilis subsp. eugracilis Brand Gilia gracilis var. euphorbioides Brand Gilia gracilis var. glabella Suksd. Gilia gracilis var. humilior (Hook.) H.St.John Gilia gracilis subsp. humilis (Greene) Brand Gilia gracilis var. micrantha (Kellogg) Brand Gilia gracilis var. minuartioides (Franch.) Borsini Gilia gracilis var. nana Brand Gilia gracilis var. pratensis Suksd. Gilia gracilis subvar. spathulifolia Speg. Gilia gracilis subsp. spirillifera Brand Gilia gracilis var. stricta Brand Gilia gracilis var. villosa Jeps. & Hoover Gilia humilis (Greene) Piper Gilia humilis subsp. glabella (Greene) Piper Gilia micrantha (Kellogg) A.Nelson Gilia microsteris Piper Gilia traskiae Eastw. ex Milliken Microsteris andicola Greene Microsteris californica Greene Microsteris diffusa A.Heller Microsteris glabella Greene Microsteris gracilis subsp. humilis (Greene) V.E.Grant Microsteris heterophylla Brockman Microsteris humilis Greene Microsteris macdougalii A.Heller Microsteris micrantha (Kellogg) Greene Microsteris stricta Greene Microsteris traskiae (Eastw. ex Milliken) Davidson & Moxley Myotoca eritrichoides Griseb. ex Brand Navarretia eritrichoides (Griseb.) Kuntze Navarretia gracilis (Hook.) Kuntze Phlox gracilis (Hook.) Greene Phlox gracilis var. humilior (Hook.) B.Boivin Phlox gracilis subsp. humilis (Greene) H.Mason Polemonium morenonis Kuntze

Microsteris is a genus of flowering plants in the phlox family containing the single species Microsteris gracilis, known by the common name slender phlox.

The segregation of this species into a genus of its own is controversial, and many botanists continue to include the plant in genus Phlox. Genetic analysis is continuing.

Description

Microsteris gracilis is an annual herb which is variable in shape, taking a decumbent, branching, sometimes almost tuftlike form or growing erect and very slender. Its maximum height approaches 20 centimeters, but it may be much smaller.

The lance-shaped leaves are 1 to 3 centimeters long and oppositely arranged except for the upper ones, which are alternate. The herbage is glandular and hairy in texture. The inflorescence at the top of the stem bears one or more small flowers.

The flower has a tubular throat around a centimeter long encased in a tubular calyx of sepals. The flat corolla has five flat-tipped or notched lobes just 1 or 2 millimeters long. The flower is white to bright pink with a yellowish throat.

Taxonomy

In 1829 William Jackson Hooker named a new species in the Gilia genus, Gilia gracilis. The genus Microsteris was named and described by Edward Lee Greene, including Microsteris gracilis. Together with its genus the species is classified in the Polemoniaceae family.

Although Microsteris is monotypic genus 13 species names have been created that are a synonym another species or one of its two accepted varieties.

The genus Myotoca with the single species Myotoca eritrichoides was created in 1907 by August Brand and attributed to August Grisebach and is synonymous with Microsteris and variety gracilis respectively. In addition there are five alternate classifications for the species that are homotypic synonyms.

Distribution

Microsteris gracilis is native to western North America from northwestern Canada to the American Midwest and West Coast, through Mexico, as well as South America from Peru to southern Chile.

In Canada it does sometimes occur in the Yukon, but its has not established a recurring population. It is stated to be introduced to the Yukon in the Flora of Alberta, but is listed as native in Plants of the World Online. In British Columbia and Alberta it is found in southern parts of the provinces. In the northwestern United States it is common throughout Washington and Oregon, mostly found in southern Idaho, and widely scattered in Montana. Southward in Wyoming it is recorded in all but four counties and is found on both the western and eastern slopes of Colorado. It reaches its easternmost native distribution in a few western counties of South Dakota and Nebraska.

In the southwestern US the species is native to all the diverse plant communities in California, with records in almost every county. It is likewise found in all but one county in Nevada and all but five counties in Utah. Plants grow in most of Arizona, but only in western counties of New Mexico. South of the border it is found in just two northwestern Mexican states, Baja California and Sonora.

References

External links

Wikimedia Commons has media related to Microsteris gracilis.

• USDA Plants Profile for Microsteris gracilis (slender phlox)
• Microsteris gracilis — U.C. Photo gallery

Wikimedia Commons has media related to Microsteris gracilis.