Hypericum tetrapetalum, the fourpetal St. Johnswort,[3] is a species of flowering plant in the St. John's wort family, Hypericaceae.[4] It is found in the Southeastern United States and Cuba.[4] It was first described by Jean-Baptiste Lamarck in 1797.[1][2]

Hypericum tetrapetalum
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Malpighiales
Family:	Hypericaceae
Genus:	Hypericum
Section:	H. sect. Myriandra
Subsection:	H. subsect. Ascyrum
Species:	H. tetrapetalum
Binomial name
Hypericum tetrapetalum Lam.[1]
Synonyms[2]
Ascyrum amplexicaule Michx. Ascyrum cubense Griseb. Ascyrum tetrapetalum (Lam.) Vail

Description

Fourpetal St. Johnswort is a perennial herb or small shrub with a woody base, growing 20–100 cm (7.9–39.4 in) tall. Young stems are two- or four-lined, becoming two-lined or terete as they age. The leaves are oblong to triangular-ovate, 5–35 mm (0.20–1.38 in) long, 4–15 mm (0.16–0.59 in) across, with heart-shaped, clasping bases. The terminal flowerheads produce one to three flowers, each flower 20–30 mm (0.79–1.18 in) in diameter with 4 bright yellow petals and about 100 stamens. It produces flowers throughout most of the year.[5][6] The capsules are three-parted.[5]

It is distinguished from the closely related Hypericum crux-andreae by its broader leaves with clasping bases.[5] Their distribution overlaps in southern Georgia and northern Florida, but apparent hybrids have not been observed.[4]

Distribution and habitat

In the United States, H. tetrapetalum is found in Alabama, Georgia, and Florida. It is also found in western Cuba.

H. tetrapetalum occurs in wet pinelands and ditches in sandy soil.[5][4]

References