Hypericum microsepalum

(Torrey & A. Gray) A. Gray ex S. Watson

Smithsonian Misc. Collect. 258: 456. 1878.

Endemic
Basionym: Ascyrum microsepalum Torrey & A. Gray Fl. N. Amer. 1: 157. 1838
Synonyms: Crookea microsepala (Torrey & A. Gray) Small Isophyllum drummondii Spach
Treatment appears in FNA Volume 6. Treatment on page 83. Mentioned on page 75.

Shrubs, erect to ascending, bushy, with ± numerous, sometimes straggling branches, 1.5–7 dm. Stems: internodes 4-lined at first, eventually 2-lined. Leaf-blades narrowly oblong or oblanceolate to linear, 5–15 × 1–3 mm, base not articulated, rounded to cuneate, margins recurved to subrevolute, apex rounded to obtuse, midrib with 1–3 pairs of branches. Inflorescences rounded-pyramidal, 1–3-flowered, narrowly branched, sometimes with 1–3-flowered dichasia or branches from to 4 proximal nodes. Flowers 15–25 mm diam.; sepals persistent, not enclosing capsule, (3–) 4 (–5), oblong or elliptic-oblong to linear, subequal or equal, 3–5 × 1–1.4 mm; petals (3–) 4 (–5), bright-yellow, obovate (larger pair) to obovate-oblong (smaller pair), 10–12 mm; stamens persistent, 60–70; ovary 3-merous, placentation parietal. Capsules cylindric-ellipsoid to narrowly ovoid-conic, 6–8 × 2.5 mm. Seeds not carinate, 0.9–1 mm; testa linear-foveolate. 2n = 18.


Phenology: Flowering late winter–spring (Feb–May), late fall (Nov).
Habitat: Low, pine flatwoods, moist to wet, on sand
Elevation: 0–100 m

Discussion

Hypericum microsepalum is related to H. cistifolium, not to the other four-petaled species attributed to Ascyrum, and can be distinguished from it by the bushier habit and smaller leaves and by the usually four-merous flowers with larger petals.

Hypericum isophyllum Steudel is an illegitimate name for H. microsepalum.

Selected References

None.

Lower Taxa

None.
... more about "Hypericum microsepalum"
reddish +  and black +
yellow;orange +
oblong;ellipsoid +
rounded;obtuse +
Norman K. B. Robson +
(Torrey & A. Gray) A. Gray ex S. Watson +
striate +  and smooth +
punctiform +
not articulated +
distinct +
rounded +  and cuneate +
Ascyrum microsepalum +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
cylindric-ellipsoid;narrowly ovoid-conic +
2.5 cm25 mm <br />0.025 m <br /> (?) +
Fla. +  and Ga. +
0–100 m +
connate +  and distinct +
1.5 cm15 mm <br />0.015 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
Low, pine flatwoods, moist to wet, on sand +
branched +  and 1-3-flowered +
axillary +  and terminal +
rounded-pyramidal +
2-lined +  and 4-lined +
terete +  and angled +
0.5 cm5 mm <br />0.005 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
oblanceolate;linear +
glanduliferous +, petiolate +, pseudopetiolate +, subsessile +, sessile +, estipulate +  and simple +
persistent +  and deciduous +
glandular-ciliate +
incompletely axile +  and parietal +
glanduliferous +
contorted +  and imbricate +
bright-yellow +
deciduous +
distinct +
obovate;obovate-oblong +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
Flowering late winter–spring (Feb–May), late fall (Nov). +
Smithsonian Misc. Collect. +
not carinate +
0.09 cm0.9 mm <br />9.0e-4 m <br /> (?) +  and 0.1 cm1 mm <br />0.001 m <br /> (?) +
persistent +
connate +  and distinct +
elliptic-oblong;linear +
subequal +
0.1 cm1 mm <br />0.001 m <br /> (0.14 cm1.4 mm <br />0.0014 m <br />) +
persistent +
connate +  and distinct +
spreading;more or less appressed +
elongate +
Crookea microsepala +  and Isophyllum drummondii +
Hypericum microsepalum +
Hypericum sect. Myriandra +
species +
scalariform +
linear-foveolate +
perennial +  and annual +
shrub +  and bushy +
erect +  and ascending +
hairy +  and glabrous +
6 +, 9 +  and 7 +