Flora of North America species comparison

The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

Hypericum tetrapetalum

fourpetal St. Johnswort
Habit Herbs (perennial) or shrubs, erect, with woody base, usually unbranched, sometimes with divaricate or ascending branches, 2–10 dm.
Stems

internodes (2–)4-lined at first, then 2-lined to terete.
Leaf

blades oblong-ovate to ovate or triangular-ovate, 5–35 × 4–15 mm, base articulated, cordate-amplexicaul, margins subrecurved, apex apiculate or obtuse to rounded, midrib with 1 pair of branches.
Inflorescences

terminal, 1(–3)-flowered, branching from apical node pseudodichotomous, sometimes with relatively short branches from to 3 proximal nodes.
Flowers

20–30 mm diam.;

sepals persistent, enclosing capsule, 4, unequal, outer broadly ovate, 7–15 × 5.5–10 mm, apex subapiculate to obtuse, inner narrowly lanceolate, 7–15 × 2–3 mm, apex acute;

petals 4, bright yellow, obovate-oblong, 10–15 mm;

stamens persistent, 100;

ovary 3-merous.
Capsules

broadly ellipsoid-ovoid to subglobose, 5–6 × 3.5–4 mm.
Seeds

not carinate, 0.7 mm;

testa shallowly scalariform.
2n

= 18.

Hypericum tetrapetalum
Phenology Flowering winter–spring (Jan–Apr), late summer (Jul–Sep).
Habitat Moist, low pinelands, ditches
Elevation 0–200 m (0–700 ft)
Distribution
from FNA
AL; FL; GA; West Indies (w Cuba)
[WildflowerSearch map]
[BONAP county map]
Discussion

Hypericum tetrapetalum differs from H. crux-andreae in having broader leaves with strongly cordate-amplexicaul bases and, nearly always, by terminal pseudodichotomous inflorescences.

(Discussion copyrighted by Flora of North America; reprinted with permission.)
Source FNA vol. 6, p. 86.
Parent taxa Hypericaceae > Hypericum > sect. Myriandra
Sibling taxa
H. adpressum, H. anagalloides, H. apocynifolium, H. ascyron, H. boreale, H. brachyphyllum, H. buckleyi, H. canadense, H. canariense, H. chapmanii, H. cistifolium, H. concinnum, H. crux-andreae, H. cumulicola, H. densiflorum, H. denticulatum, H. dolabriforme, H. drummondii, H. edisonianum, H. ellipticum, H. erythreae, H. fasciculatum, H. frondosum, H. galioides, H. gentianoides, H. graveolens, H. gymnanthum, H. harperi, H. hypericoides, H. kalmianum, H. lissophloeus, H. lloydii, H. lobocarpum, H. maculatum, H. majus, H. microsepalum, H. mutilum, H. myrtifolium, H. nitidum, H. nudiflorum, H. paucifolium, H. perforatum, H. prolificum, H. pseudomaculatum, H. punctatum, H. radfordiorum, H. scouleri, H. setosum, H. sphaerocarpum, H. suffruticosum, H. tenuifolium, H. virgatum, H. ×mitchellianum
Synonyms Ascyrum amplexicaule, A. cubense, A. tetrapetalum
Name authority Lamarck: in J. Lamarck et al., Encycl. 4: 153. (1797)
Web links 
Unless otherwise noted, all data comes from the online version of the Flora of North America, who have made most of their content available via a Creative Commons license (CC BY 4.0).



Type/paste one or more Latin names into the boxes above; matching taxa will show up below the box as you type. You can use the up/down arrow keys to move through the list.

(If the plant you're looking for doesn't show up in the auto-complete list, that means it either isn't described in Flora of North America yet, or it's listed under a synonym. And please note that Flora of North America is still missing several plant families, including Apiaceae, Boraginaceae, and Polemoniaceae.)

Choose a data source: Flora of North America

The species comparison tool is brought to you by:
Northwest Wildflowers