Atriplex saccaria var. cornuta

(M. E. Jones) S. L. Welsh

Rhodora 102: 420. 2001.

Common names: Flat-horn orach
Endemic
Basionym: Atriplex cornuta M. E. Jones Proc. Calif. Acad. Sci., ser. 2, 5: 718. 1895
Synonyms: Atriplex argentea var. cornuta (M. E. Jones) M. E. Jones
Treatment appears in FNA Volume 4. Treatment on page 349. Mentioned on page 348.

Herbs, annual, rather low, sprawling, mainly 1.5–3 dm and as broad or broader. Stems terete or angled. Leaves: petiole mainly 1–3 cm, gradually shortened distally; blade rhombic to deltoid or ovate, 10–25 mm and as broad or broader, base broadly to narrowly cuneate, apex acute to rounded. Staminate flowers in small sessile glomerules axillary in distalmost bracteate leaves. Fruiting bracteoles dimorphic, those on stipes (2–) 4–15 mm or longer, with surfaces covered with flattened processes, sessile one cuneate as in type variety.


Phenology: Flowering late summer–fall.
Habitat: Salt desert shrub communities, on fine-textured saline substrates of Morrison and Mancos Shale formations
Elevation: 1400-1500 m

Discussion

Atriplex saccaria var. cornuta is a Colorado Plateau endemic.

The rhombic to deltoid or flabellate, broadly cuneate leaves of this variety bear a superficial resemblance to those of Atriplex argentea, especially portions of var. rydbergii, possibly resulting in Jones’ subsequent placement of the taxon. Some specimens appear to grade with the partially sympatric and highly variable var. saccaria, especially with the phase that has passed under the name A. caput-medusae.

Selected References

None.

Lower Taxa

None.

"broader" is not a number."/2" is not declared as a valid unit of measurement for this property."shortened" is not a number."dm" is not declared as a valid unit of measurement for this property."dm" is not declared as a valid unit of measurement for this property.

dentate +, truncate +  and undulate-dentate +
acute +  and rounded +
hornlike +, cristate +  and flat +
Stanley L. Welsh +
(M. E. Jones) S. L. Welsh +
slippery +
aromatic +
cuneate +
Atriplex cornuta +
0.6 cm6 mm <br />0.006 m <br /> (4 cm40 mm <br />0.04 m <br />) +
rhombic +  and deltoid or ovate +
1 cm10 mm <br />0.01 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
persistent +  and deciduous +
reddish-brown +, black +, brown +  and green +
0 cm0 mm <br />0 m <br /> (?) +
cuneate +  and ovate or obovate +
not crested +
5-parted +
rounded +
Flat-horn orach +
N.Mex. +  and Utah. +
1400-1500 m +
tuberculate +
1 +  and 3 +
unisexual +  and bisexual +
not +  and connate +
enlarged +
Salt desert shrub communities, on fine-textured saline substrates of Morrison and Mancos Shale formations +
bladderlike +
terminal +  and axillary +
opposite +  and alternate +
deciduous +  and persistent +
not winged +  and winged +
in some subhastately lobed or sometimes undulate-dentate , apex +  and entire +
lobed +  and serrate-dentate +
suborbicular +  and round-triangular +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
inferior +, half-inferior +  and superior +
crassinucellate +  and bitegmic +
campylotropous +
1 +  and single +
persistent +  and deciduous +
(1-)3-5-lobed +
papery +  and chartaceous +
1 cm10 mm <br />0.01 m <br /> (3 cm30 mm <br />0.03 m <br />) +
Flowering late summer–fall. +
flattened +  and cuneate +
subopposite +  and alternate +
bulbous +  and taprooted +
fusiform +
fleshy +  and fibrous +
verrucate +  and striate +
brownish +  and whitish +
flattened +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.23 cm2.3 mm <br />0.0023 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
cylindric +
3 +  and 5 +
opposite +  and alternate +
angled +  and terete +
succulent +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
sessile +  and petiolate +
reduced;small +
horizontal +  and vertical +
verrucate +
Atriplex argentea var. cornuta +
Atriplex saccaria var. cornuta +
Atriplex saccaria +
variety +
dicotyledonous +
broader +  and broad +