Hypericum lissophloeus

W. P. Adams

Contr. Gray Herb. 189: 21. 1962.

Common names: Smooth-barked St. John’s wort
Conservation concernEndemic
Treatment appears in FNA Volume 6. Treatment on page 80. Mentioned on page 76.

Shrubs, erect, sparsely branched, forming dense clumps sometimes with prop-roots, to 40 dm, bark smooth and metallic-silvery, without laticifers, exfoliating in thin, curled plates. Stems: internodes 4-lined at first, soon 4-angled, then terete, dull silvery, glaucous. Leaf-blades linear-subulate to acicular, (9–) 12–17 × 0.5–0.8 mm, glaucous, base articulated, parallel or almost so, margins revolute, apex obtuse to rounded, midrib unbranched. Inflorescences narrowly cylindric, 1–3-flowered, usually with paired flowers or triads from to 9 proximal nodes. Flowers 20 mm diam.; sepals deciduous, not enclosing capsule, 5, linear-subulate, subequal, 7–8 × 0.5–0.8 mm, glaucous; petals 5, bright-yellow, obovate-spatulate, 10–12 mm; stamens deciduous, 170–220; ovary 3-merous; styles 5 mm. Capsules narrowly ovoid to ellipsoid, 6–7 × 2.5–3.5 mm. Seeds narrowly carinate, 1–1.6 mm; testa coarsely reticulate-sulcate. 2n = 18.


Phenology: Flowering summer–early fall (Jun–Oct).
Habitat: Pond and lake margins to 1.5 m deep water
Elevation: 0–10 m

Discussion

Of conservation concern.

Hypericum lissophloeus is found in Bay and Washington counties. The larger capsules, one- to three-flowered, lateral inflorescence branches, and smooth-polished, metallic bark (that exfoliates like that of Betula species) are among the features that distinguish H. lissophloeus from H. fasciculatum, H. nitidum, and their allies (H. brachyphyllum and H. chapmanii).

Selected References

None.

Lower Taxa

None.
... more about "Hypericum lissophloeus"
reddish +  and black +
yellow;orange +
oblong;ellipsoid +
obtuse;rounded +
Norman K. B. Robson +
W. P. Adams +
metallic-silvery +
striate +  and smooth +
exfoliating +
punctiform +
articulated +
almost +  and parallel +
distinct +
Undefined sect. Myriandra +
0.6 cm6 mm <br />0.006 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
narrowly ovoid;ellipsoid +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.35 cm3.5 mm <br />0.0035 m <br />) +
Smooth-barked St. John’s wort +
0–10 m +
connate +  and distinct +
20 cm200 mm <br />0.2 m <br /> (?) +
Pond and lake margins to 1.5 m deep water +
axillary +  and terminal +
terete +  and 4-angled +
0.9 cm9 mm <br />0.009 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
1.2 cm12 mm <br />0.012 m <br /> (1.7 cm17 mm <br />0.017 m <br />) +
linear-subulate;acicular +
0.5mm;0.8mm +
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-spatulate +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
Flowering summer–early fall (Jun–Oct). +
Contr. Gray Herb. +
carinate +
0.1 cm1 mm <br />0.001 m <br /> (?) +  and 0.16 cm1.6 mm <br />0.0016 m <br /> (?) +
deciduous +
connate +  and distinct +
linear-subulate +
subequal +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
Conservation concern +  and Endemic +
connate +  and distinct +
spreading;more or less appressed +
elongate +
5 cm50 mm <br />0.05 m <br /> (?) +
Ascyrum +, Crookea +, Sanidophyllum +  and Sarothra +
Hypericum lissophloeus +
Hypericum sect. Myriandra +
species +
reticulate-sulcate +
scalariform +
reticulate +  and foveolate +
perennial +  and annual +
hairy +  and glabrous +
6 +, 9 +  and 7 +