Hypericum tetrapterum

Hypericum tetrapterum
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Rosids
Order:	Malpighiales
Family:	Hypericaceae
Genus:	Hypericum
Species:	H. tetrapterum
Binomial name
Hypericum tetrapterum Fries
Synonyms
Hypericum quadrangulum

Hypericum tetrapterum (syn. H. quadrangulum) is a herbaceous perennial plant species in the flowering plant family Hypericaceae. Its common names include St. Peter's wort, Peterwort, square stemmed St. John's wort, and square stalked St. John's wort.

Description

Hypericum tetrapterum is a rhizomatous, glabrous perennial plant growing to about 60cm in height. The stems are square in cross section, with conspicuous wings at the corners. The leaves are in opposite pairs, simple and entire, and have many translucent glandular dots. The yellow flowers are 9-13mm diameter and there may be black glands on the five petals and sepals, as well as on the leaves.^[1]:340

Distribution

Hypericum tetrapterum is common in damp habitats throughout Europe. ^[2]

References

1. Stace, C.A. (2010). New flora of the British isles (Third ed.). Cambridge, U.K.: Cambridge University Press. ISBN 9780521707725.
2. "Hypericum tetrapterum L.". Retrieved 19 August 2015.