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Douglasdeweya deweyi
UTC 233615

Douglasdeweya wangii
UTC177406

Douglasdeweya wangii

Distribution of species

Douglasdeweya wangii spikelet

 

Douglasdeweya wangii spikelets

Genomic constitution

StP, the St genome being derived from Pseudoroegneria and the P genome from Agropyron.

Distinguishing features

Perennial plants with solitary spikelets. Glumes and lemmas rather tough, keeled distally and mucronate.

Description

Plants perennial, loosely clumped or stoloniferous. Culms 50-100 cm tall.

Leaf blades 1.5-4 mm wide.

Inflorescence spikelike, 9-20 cm long with 9-21 nodes; rachis tough, lower internode 14-21 mm long; middle internodes 8-12 mm long; disarticulation below the florets.  

Spikelets solitary, tangential to the rachis, 11-15 mm long, with 5-7 florets.

Glumes 6-8.5 mm long, almost as long as the adjacent lemmas, lanceolate, glabrous, mucronate.

Lemmas glabrous externallly, sometimes densely hairy on the inner surface, mucronate, not awned. Paleas equaling the lemmas, tapering to the narrow tip, keels somewhat coarsely toothed, teeth not widely spaced. Lodicules slightly lobed. Anthers 3-7 mm long.

Size

Only two species are known in the genus, Douglasdeweya deweyi and Douglasdeweya wangii.

Distribution

Western Iran and the Caucasus

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Alternative interpretations

The genus was initially circumscribed on the basis of its genomic constitution and distinction from the genera represented by its ancestral genomes. No wild specimens have been identified as yet. Its members are currently included in one of Elymus, Pseudoroegneria, or Elytrigia.

Type species

Douglasdeweya deweyi (K.B. Jensen, S.L. Hatch & Wipff) C.Yen, J.L. Yang, & B.R. Baum

Known problems

There is little information on the distribution of the two species in this genus, it being known only from specimens grown from seed.

References

Yen, C., Yang, JL., and Baum, BR. 2005. Douglasdeweya : A new genus, with a new species and a new combination (Triticeae: Poaceae). Canadian Journal of Botany 83: 413-419