Dimeresia

Life-forms

Classification System: APG IV

Superregnum: Eukaryota
Regnum: Plantae
Cladus: Angiosperms
Cladus: Eudicots
Cladus: Core eudicots
Cladus: Asterids
Cladus: Campanulids
Ordo: Asterales

Familia: Asteraceae
Subfamilia: Asteroideae
Tribus: Chaenactideae
Genus: Dimeresia
Species: D. howellii
Name

Dimeresia A.Gray

monotypic taxon

References

A.Gray 1886. Synoptical Flora of North America 1(2): 448–449.

Links

International Plant Names Index. 2017. Dimeresia. Published online. Accessed: Dec. 24 2017.
The Plant List 2013. Dimeresia in The Plant List Version 1.1. Published on the internet. Accessed: 2017 Dec. 24.
Tropicos.org 2017. Dimeresia. Missouri Botanical Garden. Published on the internet. Accessed: 2017 Dec. 24.
Hassler, M. 2017. Dimeresia. World Plants: Synonymic Checklists of the Vascular Plants of the World In: Roskovh, Y., Abucay, L., Orrell, T., Nicolson, D., Bailly, N., Kirk, P., Bourgoin, T., DeWalt, R.E., Decock, W., De Wever, A., Nieukerken, E. van, Zarucchi, J. & Penev, L., eds. 2017. Species 2000 & ITIS Catalogue of Life. Published on the internet. Accessed: 2017 Dec 24. Reference page.

Vernacular names
English: Doublet

Dimeresia is a monotypic genus in the sunflower family containing the single species Dimeresia howellii, known by the common name doublet.[2][3][4]

Distribution

This uncommon plant is endemic to an area of the Great Basin region in the western United States, in northeastern California, southeastern Oregon, southwestern Idaho, and northwestern Nevada.[2][5][6][7]

It grows in dry volcanic soils, primarily on the Modoc Plateau volcanic plain, at elevations of 1,500–2,400 metres (4,900–7,900 ft).[5]
Description

Dimeresia howellii is a very tiny annual flowering plant rarely exceeding 4 centimeters in height or width. It forms a small tuft on the ground with several oval-shaped leaves, and is cobwebby at base and glandular above.[5]

The inflorescence has tiny white to purple bell-shaped flowers each a few millimeters long.[5] The flowering period is May to August.[2]
References

Flann, C (ed) 2009+ Global Compositae Checklist search for Dimeresia
Calflora: Dimeresia howellii
Gray, Asa. 1886. Synoptical Flora of North America 1(2): 448–449
Tropicos, Dimeresia − A. Gray
Jepson eFlora: Dimeresia howellii[permanent dead link]
Flora of North America, Dimeresia A. Gray
Biota of North America Program 2013 county distribution map