Streptanthus maculatus

Nuttall

J. Acad. Nat. Sci. Philadelphia 5: 134, plate 7. 1825.

IllustratedEndemic
Synonyms: Streptanthus maculatus subsp. obtusifolius (Hooker) Rollins Streptanthus obtusifolius
Treatment appears in FNA Volume 7. Treatment on page 718. Mentioned on page 703, 721.

Annuals; (glaucous), usually glabrous throughout (sometimes stem-bases pubescent). Stems unbranched or branched distally, 1.7–10.6 dm, (trichomes 0.05–0.5 mm). Basal leaves (soon withered); rosulate; petiolate; blade similar to cauline. Cauline leaves: blade broadly ovate to broadly oblong or lanceolate, 2–15 cm × 10–80 mm, (smaller distally), base amplexicaul, margins entire, (apex acute to acuminate or rounded). Racemes ebracteate, (dense or lax). Fruiting pedicels divaricate-ascending, (straight), 4–7 mm. Flowers: calyx campanulate; sepals (erect), purplish, 4–9 mm, (lateral pair rarely with subapical callus, 0.1–0.3 mm), not keeled; petals (widely spreading to somewhat reflexed), magenta (with deep purple center), 11–21 mm, blade 6–12 × 5–11 mm, margins not crisped, claw 5–10 mm, narrower than blade; stamens tetradynamous; filaments: median pairs (distinct), 5–7 mm, lateral pair 3–5 mm; anthers (all) fertile, 3–4 mm; gynophore 0.7–1.5 mm. Fruits ascending, smooth, straight, flattened, 6–11.4 cm × 2–3 mm; valves each with prominent midvein; replum straight; ovules 56–92 per ovary; style 1–2.5 mm; stigma strongly 2-lobed. Seeds broadly oblong, 2–2.5 × 1–1.3 mm; wing 0.2–0.3 mm wide, continuous.


Phenology: Flowering Apr–May.
Habitat: Near creeks, roadside banks, moist bottoms, open oak woods, moist land in woods, rocky bluffs, ledges, dry talus slopes, rock crevices, pine-hickory forests
Elevation: 200-500 m

Discussion

Streptanthus maculatus is distributed in Arkansas in Garland, Hot Springs, Montgomery, Pike, Polk, Pulaski, and Saline counties; in Oklahoma in Latimer, Le Flore, McCurtain, and Pushmataha counties; and in Texas in Anderson, Cherokee, Gregg, and Smith counties.

R. C. Rollins (1993) divided Streptanthus maculatus into two subspecies based on the presence versus absence of the subapical callus on sepals and on leaf shape. Subspecies maculatus was said to differ from subsp. obtusifolius by the absence (versus presence) of the sepal callus and by having lanceolate (versus broadly ovate) cauline leaves. These highly variable characters do not covary.

Selected References

None.

Lower Taxa

None.

"elongated" is not a number."thick" is not a number."dm" is not declared as a valid unit of measurement for this property.

... more about "Streptanthus maculatus"
linear +  and oblong +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Ihsan A. Al-Shehbaz +
Nuttall +
appendaged +  and unappendaged +
not +  and auriculate +
0.6 cm6 mm <br />0.006 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
lyrate-pinnatifid +, dentate +  and entire +
dissected +, repand +, sinuate +, crenate +  and dentate +
broadly ovate;broadly oblong or lanceolate +
much smaller +  and reduced +
0.5 cm5 mm <br />0.005 m <br /> (1.1 cm11 mm <br />0.011 m <br />) +
campanulate +
branched +  and simple +
petiolate +  and sessile +
well-developed +
distinct +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
differentiated +
narrower +
emarginate +  and entire +
Ark. +, Okla. +  and Tex. +
200-500 m +
straight +  and curved +
not winged +  and unappendaged +
connate +  and distinct +
lateral +  and median +
0.3 cm3 mm <br />0.003 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
zygomorphic +  and actinomorphic +
magenta;purplish +
not keeled +
1.1 cm11 mm <br />0.011 m <br /> (2.1 cm21 mm <br />0.021 m <br />) +
latiseptate +, stipitate +  and subsessile +
straight +
6 cm60 mm <br />0.06 m <br /> (11.4 cm114 mm <br />0.114 m <br />) +
flattened +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.07 cm0.7 mm <br />7.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
Near creeks, roadside banks, moist bottoms, open oak woods, moist land in woods, rocky bluffs, ledges, dry talus slopes, rock crevices, pine-hickory forests +
sessile +  and petiolate +
alternate +, not +  and rosulate +
cauline +  and basal +
connate +  and distinct +
decurrent +
not crisped +
tenuinucellate +, crassinucellate +  and bitegmic +
campylotropous +  and anatropous +
unequal +
brownish +, purple +, pink +, yellow +  and white +
rudimentary +
oblong +  and ovate +
Flowering Apr–May. +
trinucleate +  and 3(-11)-colpate +
J. Acad. Nat. Sci. Philadelphia +
divaricate-ascending +
stout +  and slender +
0.4 cm4 mm <br />0.004 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
mucilaginous +
aseriate +, uniseriate +  and biseriate +
not +  and mucilaginous +
white +, black +, brown +  and yellow +
0.2 cm2 mm <br />0.002 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
persistent +  and caducous +
distinct +
reduced +
latiseptate +, schizocarpic +, samaroid +  and lomentaceous +
indehiscent +  and dehiscent +
angustiseptate +, flat +, angled +, terete +, torulose +, not +, segmented +  and nutletlike +
Illustrated +  and Endemic +
tetradynamous +
branched +  and unbranched +
procumbent +  and decumbent +
ascending +  and erect +
subsessile +, sessile +  and petiolate +
persistent +
distinct +
0.1 cm1 mm <br />0.001 m <br /> (0.25 cm2.5 mm <br />0.0025 m <br />) +
Streptanthus maculatus subsp. obtusifolius +  and Streptanthus obtusifolius +
Streptanthus maculatus +
Streptanthus +
species +
dendritic +  and simple +
coiled +, 1-7-veined +  and veined +
pubescent +  and glabrous +
anastomosing +
perennial +, biennial +  and annual +
subshrub +  and shrub +
aquatics +  and terrestrial +
glabrous +  and pubescent +
0.2mm;0.3mm +