Tradescantia occidentalis var. scopulorum

(Rose) E. S. Anderson & Woodson

Contr. Arnold Arbor. 9: 106. 1935.

Endemic
Basionym: Tradescantia scopulorum Contr. U. S. Natl. Herb. 5: 205. 1899
Treatment appears in FNA Volume 22.

Stems 14–35 cm. Leaves: blade 5–45 × 0.4–0.9 cm. Flowers: pedicels 1–2 cm, glabrous; sepals 5–8 mm, glabrous; petals bright blue, 0.7–1 cm.


Phenology: Flowering spring–summer, fall (Apr–Aug, Oct).
Habitat: Moist canyons and stream banks

Discussion

The two varieties intergrade; the only absolute difference between them is sepal pubescence. Tradescantia occidentalis var. scopulorum evidently was defined more broadly by W. C. Martin and C. R. Hutchins (1980), so the distribution I have shown for New Mexico could be too wide. A broader circumscription of this variety has also been used by others (C. Sinclair 1967; M. Bolick 1986), but I have not accepted these records.

Most specimens of Tradescantia occidentalis from Arkansas and Louisiana have an apical tuft of eglandular hairs on the sepals, a character acquired through introgression with T. ohiensis (E. Anderson and R. E. Woodson Jr. 1935).

Tradescantia occidentalis var. melanthera has been described for plants from Arkansas, Louisiana, eastern Texas and eastern Oklahoma that have dark anther connectives (D. T. MacRoberts 1977). I have not been able to recognize this character in dried specimens with any consistency.

Selected References

None.

Lower Taxa

None.
glabrous +  and glaucous +
acuminate +
Robert B. Faden +
(Rose) E. S. Anderson & Woodson +
Tradescantia scopulorum +
petiolate +  and sessile +
5 cm50 mm <br />0.05 m <br /> (45 cm450 mm <br />0.45 m <br />) +
linear-lanceolate +
succulent +
0.4 cm4 mm <br />0.004 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
umbel-like +
Ariz. +  and N.Mex. +
Moist canyons and stream banks +
thyrsiform +  and cymose +
glabrous +  and glaucous +
cauline +  and basal +
differentiated +
1 cm10 mm <br />0.01 m <br /> (2 cm20 mm <br />0.02 m <br />) +
bright blue +
distinct +
not clawed +  and ovate +
unequal +
0.7 cm7 mm <br />0.007 m <br /> (?) +  and 1 cm10 mm <br />0.01 m <br /> (?) +
Flowering spring–summer, fall (Apr–Aug, Oct). +
Contr. Arnold Arbor. +
0.2 cm2 mm <br />0.002 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
distinct +
subequal +
0.5 cm5 mm <br />0.005 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
staminodial +
14 cm140 mm <br />0.14 m <br /> (35 cm350 mm <br />0.35 m <br />) +
not +  and enlarged +
slender +
Rhoeo +, Setcreasea +  and Zebrina +
Tradescantia occidentalis var. scopulorum +
Tradescantia occidentalis +
variety +
ascending +  and erect +