''Howellanthus'' is a monotypic genus of flowering plants in the

borage family Boraginaceae, the borage or forget-me-not family, includes about 2,000 species of shrubs, trees and herbs in 146, to 156 genera with a worldwide distribution. The APG IV system from 2016 classifies the Boraginaceae as single family of the orde ...

containing the single species ''Howellanthus dalesianus'', commonly known as Scott Mountain phacelia or Howell's phacelia. Until 2010 the plant was known as ''Phacelia dalesiana''.Walden, G. K. and R. Patterson. (2010). ''Howellanthus dalesianus'', Recognition of a new genus and species in Tribe Phacelieae (Boraginaceae). ''Madroño'' 57:4 268–273. 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 els ...

to the southern

Klamath Mountains The Klamath Mountains are a rugged and lightly populated mountain range in northwestern California and southwestern Oregon in the western United States. As a mountain system within both the greater Pacific Coast Ranges and the California Coast ...

of northern

California California is a state in the Western United States, located along the Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the most populous U.S. state and the 3rd largest by area. It is also the ...

, including the Scott Mountains for which it is named. It grows in mountain forests and meadows often on serpentine soils.

Description

''Phacelia dalesiana'' is a perennial herb producing a few decumbent stems up to about 15 centimeters long, forming a patch on the ground. It is glandular and hairy in texture. The leaves are located in a rosette, with a few smaller ones along the stems. They are oval and smooth-edged. 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 ...

is a small curving cluster of flowers each just under a centimeter wide. The flower is white with small purple streaks at the throat. There are five protruding

stamen The stamen (plural ''stamina'' or ''stamens'') is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium., p. 10 Morphology and terminology A stamen typically consists of a stalk called the filam ...

s tipped with large purple anthers. It blooms between May and August, the timing dependent on

snowmelt In hydrology, snowmelt is surface runoff produced from melting snow. It can also be used to describe the period or season during which such runoff is produced. Water produced by snowmelt is an important part of the annual water cycle in many part ...

Ecology

The plant is a

paleoendemic Paleoendemism along with neoendemism is a possible subcategory of endemism. Paleoendemism refers to species that were formerly widespread but are now restricted to a smaller area. Neoendemism refers to species that have recently arisen, such as thr ...

, its morphology unique among the phacelias, and probably a

relict A relict is a surviving remnant of a natural phenomenon. Biology A relict (or relic) is an organism that at an earlier time was abundant in a large area but now occurs at only one or a few small areas. Geology and geomorphology In geology, a r ...

persisting in areas of

ultramafic Ultramafic rocks (also referred to as ultrabasic rocks, although the terms are not wholly equivalent) are igneous and meta-igneous rocks with a very low silica content (less than 45%), generally >18% MgO, high FeO, low potassium, and are compos ...

rock substrate in a small section of the Siskiyou-

Trinity Mountains The Trinity Mountains are a subrange of the Klamath Mountains, one of the ranges within the California Coast Ranges and part the greater Pacific Coast Ranges, the coastal mountain system extending from Mexico to Alaska. The Trinity Mountains subra ...

Taxonomy

The new name honors botanist

John Thomas Howell John Thomas Howell (November 6, 1903 – May 7, 1994) was an American botanist and taxonomist. He became an expert of '' Eriogonum'' (buckwheat) species, which are widely represented in the native California flora. He was the assistant of Ali ...

and his friend, plant collector Ella Dales Miles Cantelow. The type location is the summit of Scott Mountain in

Trinity County, California Trinity County is a county located in the northwestern portion of the U.S. state of California. Trinity County is rugged, mountainous, heavily forested, and lies along the Trinity River (for which it is named) within the Salmon and Klamath Moun ...

, near

California State Route 3 State Route 3 (SR 3) is a state highway in the U.S. state of California that serves Trinity and Siskiyou counties. It runs from SR 36 north along the shore of Trinity Lake, Fort Jones and Etna. The route then approaches Yreka, intersecting ...

and the

Pacific Crest Trail The Pacific Crest Trail (PCT), officially designated as the Pacific Crest National Scenic Trail, is a long-distance hiking and equestrian trail closely aligned with the highest portion of the Cascade and Sierra Nevada mountain ranges, which lie ...

, the type locality for many species of rare endemic plants.

References

External links

Jepson Manual Treatment - ''Phacelia dalesiana''''Phacelia dalesiana'' - Photo gallery
Boraginaceae Endemic flora of California Flora of the Klamath Mountains Natural history of Trinity County, California Phacelia Monotypic asterid genera Taxa named by John Thomas Howell Flora without expected TNC conservation status {{Hydrophylloideae-stub