Pseudoclappia watsonii

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Pseudoclappia watsonii
Systematics
Order : Astern-like (Asterales)
Family : Daisy family (Asteraceae)
Subfamily : Asteroideae
Tribe : Tageteae
Genre : Pseudoclappia
Type : Pseudoclappia watsonii
Scientific name
Pseudoclappia watsonii
AMPowell & BLTurner

Pseudoclappia watsonii (English common name : Watson's false clappia) is an extremely rare or already extinct species of plant from the Asteraceae family. It occurs or occurred in western Texas .

features

Pseudoclappia watsonii is a complex branched, rounded shrub that reaches a height of 25 to 75 cm. The numerous thin, white stems are ascending in an arc. The leaves are mostly arranged alternately on the stem, but almost opposite at its base. The fleshy and bald leaf blade is linear, almost cylindrical, with a length of usually 6 to 13 (3 to 17) mm and a width of 0.6 to 1.0 mm. The leaf margin is sharply pointed.

The cup-shaped inflorescences hang individually from the branched tips of the 4 cm long, erect, straight to twisted inflorescence axis. The inflorescence axis has isolated, awl bracts with a length of 3 to 5 mm. The 11 to 14 mm long cup shell (involucre) is broadly inverted-conical. The seven to twelve bracts are arranged in three to four rows. The 12.0 to 14.5 mm long and 2.5 to 4.0 mm wide inner bracts are elongated-lanceolate. The thin-skinned edge of the bracts is pointed to pointed and slightly ciliate near the tip. The outer bracts are 5 to 8 mm long. The flower heads contain about 25 tubular flowers as well as four to eleven ray-flowers. With the yellow ray-flowers the corolla-tube is 4 to 5 mm long and the elongated-elliptical corolla- tongue is 9 to 13 mm long and 2.0 to 3.5 mm wide. The yellow tubular flowers have an 8 to 10 mm long corolla and the five corolla lobes about 0.5 mm long. The stylus branches are about 2 mm long.

The black achenes are 4.0 to 5.2 mm long, slightly diamond-shaped to square in cross-section and densely hairy with 0.3 to 0.5 mm long, pressed or erect hairs. The pappus consists of numerous unsymmetrical 3 to 11 mm long bristles.

The flowering period extends from May to August.

Occurrence and socialization

Pseudoclappia watsonii is endemic to the Chihuahua Desert in the Trans-Pecos region of western Texas in Brewster County , Hudspeth County, and Jeff Davis Counties . It grows in desert-like bushland on dry, stony, gypsum-containing mud hills and arroyos . Pseudoclappia watsonii thrives in association with the creosote bush , agave lechuguilla , Xylorhiza wrightii and some acacia , condalia , erioneuron and palm lily species .

status

Pseudoclappia watsonii is only known from two collections from the 1970s. She has not been found since then.

literature

  • Jackie M. Poole, William R. Carr, Dana M. Price: Rare plants of Texas: a field guide . Texas A&M University Press, 2007. ISBN 978-158-544-557-8 : pp. 410-411

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