Dudleya

Dudleya greenei

Dudleya is a genus of flowering plants in the family Crassulaceae ( Crassulaceae ). The botanical name of the genus honors the American botanist William Russel Dudley ( 1849-1911 ).

  • 3.1 Literature
  • 3.2 Notes and references

Description

Vegetative characteristics

The species of the genus Dudleya are perennial, rosette plants with mostly bare fibrous roots and succulent leaves. Your instincts are not branched or branched, then usually dichotomous. They are at their base mostly covered with more or less dried leaves or leaf bases. The shoots are mostly short and somewhat upright and reach diameters between 10 and 40 millimeters (rare 1.5 to 90 mm). The rosettes are terminally on the shoots. They have a diameter from 3 to 25 centimeters ( 1 to 50 inches rarely ), and consist of 20 to 40, often 3 to 120 sheets. The leaves are very variable in shape. Usually they are more or less oblong to oblong ( wrong ) lanceolate. The upper leaf surface is usually more or less flat or slightly concave to rinnig. Your base is usually somewhat rounded to concave. They are fully connected to a broad base with the stem axis and widened at the base often. The blade tip is obtuse - rounded to sharp - pointed. The glauken up tight floured sheets are usually evergreen. They are 1-10 cm (rarely 0.6 to 40 centimeters) long, 0.2 to 3 cm (rarely up to 10 cm) wide and 2 to 6 mm (rarely 1 to a maximum of 25 mm) thick.

Inflorescences and flowers

The individual to numerous, usually more or less erect to ascending flowering stems emerge from the leaf axils annually. They are 5 to 40 centimeters ( up to 100 cm) long. The zymöse inflorescence consists of 3-20 (rarely 2-30 ) flowers. The five-fold (rarely four-fold ) scentless flowers are obdiplostemon. The calyx is 3-8 mm (rarely 2-9 mm) long. Its sepals are fused together at the base. Your free sepals are 1.5 to 6 mm (rarely 1-8 mm) long. The corolla has diameter from 3.5 to 23 millimeters and a length of 1-4 millimeters ( 0.5 to 10 millimeters, rare ). Your usually pale yellowish to yellow petals are usually somewhat elliptical to oblong or ovate. The corolla lobes are more or less erect or bent back slightly straddling - spread from the middle to the tip up.

The ten stamens are in two circles. They are shorter than petals. The dust bags are usually yellow, and 1 to 2 millimeters long. The gestutzen Nektarschüppchen are 0.5 to 2 millimeters wide. The stylus is slim.

Fruit and seeds

The fruit is a more or less brown or brownish red, and only rarely follicle. The information contained in it more or less brown, narrowly spindle-shaped seeds are 0.5 to 1.5 millimeters in size. Your seed coat is ribbed.

Systematics and distribution

The genus Dudleya is in southwestern Oregon, distributed in southern Nevada, in central and western Arizona and California in the United States and in the Mexican states of Sonora and Baja California, where the plants grow in most coastal areas primarily on rocky places.

The first description by Nathaniel Lord Britton and Joseph Nelson Rose was published in 1903. After Joachim Thiede the genus Dudleya is divided into three subgenera with the following types:

  • Subgenus Dudleya Dudleya abramsii Rose Dudleya abramsii subsp. abramsii
  • Dudleya abramsii subsp. affinis C.M. Nakai
  • Dudleya abramsii subsp. bettinae ( Hoover ) Bartel
  • Dudleya abramsii subsp. murina ( Eastw. ) Moran
  • Dudleya abramsii subsp. parva ( Rose & Davidson) Bartel
  • Dudleya cymosa subsp. costatifolia Bartel & Shevock
  • Dudleya cymosa subsp. crebrifolia C.M. Nakai & Verity
  • Dudleya cymosa subsp. cymosa
  • Dudleya cymosa subsp. marcescens Moran
  • Dudleya cymosa subsp. ovatifolia ( Britton ) Moran
  • Dudleya cymosa subsp. paniculata ( Jeps. ) C.M. Nakai
  • Dudleya cymosa subsp. pumila (Rose) C.M. Nakai
  • Dudleya nubigena subsp. cerralvensis Moran
  • Dudleya nubigena subsp. nubigena
  • Dudleya pulverulenta subsp. arizonica (Rose) Moran
  • Dudleya pulverulenta subsp. pulverulenta
  • Dudleya saxosa subsp. aloides (Rose) Moran
  • Dudleya saxosa subsp. collomiae (Rose ex C.V. Morton ) Moran
  • Dudleya saxosa subsp. saxosa
  • Subgenus Stylophyllum ( Britton & Rose) Moran Dudleya anomala ( Davidson) Moran
  • Dudleya attenuata ( S. Watson ) Moran Dudleya attenuata subsp. attenuata
  • Dudleya attenuata subsp. orcuttii (Rose) Moran
  • Dudleya virens subsp. Extima Moran
  • Dudleya virens subsp. Hassei (Rose) Moran
  • Dudleya virens subsp. insularis (Rose) Moran
  • Dudleya virens subsp. virens
  • Subgenus Hasseanthus (Rose) Moran Dudleya blochmaniae ( Eastw. ) Moran, with the subspecies: Dudleya blochmaniae subsp. blochmaniae
  • Dudleya blochmaniae subsp. brevifolia ( Moran ) Moran
  • Dudleya blochmaniae subsp. insularis Moran

The genus also still the hybrids are Dudleya × semi teres ( Rose) Moran and Dudleya × sproulii PH Thomson.

Evidence

Perennial plant Glaucous testa (botany)
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