Hypericum harperi

Hypericum harperi
Scientific classification
Kingdom:	Plantae
Clade:	Tracheophytes
Clade:	Angiosperms
Clade:	Eudicots
Clade:	Rosids
Order:	Malpighiales
Family:	Hypericaceae
Genus:	Hypericum
Section:	H. sect. Trigynobrathys
Species:	H. harperi
Binomial name
	Hypericum harperi; R.Keller
Synonyms
	H. denticulatum var. acutifolium Fern. & B.G.Schubert;

Last updated September 04, 2022

Hypericum harperi, the sharplobe St. Johnswort or Harper's St. John's wort, is a perennial flowering plant in the family Hypericaceae. It is an aquatic herb native to southeast North America. H. harperi has a diploid chromosome number of 24.

Taxonomy

Webb, in his dissertation, referred to H. incertum as the cypress pond St. John's wort. When Steudel transferred the species of Brathys to Hypericum , he created the nom. nov. for Brathys lanceolata due to the name H. lanceolatum already existing for an Old World species. After finishing his dissertation, Webb annotated the type of B. lanceolata/H. incertum and henceforth used the name H. harperi.^[1]

Though similar to H. denticulatum var. acutifolium (and previously identified as that variety), H. harperi remains distinct in its aquatic habitat and related aerenchymatous stem base. In addition to morphological differences, H. harperi contains C-glycosyl flavones which var. acutifolium lacks.^[2] No other species of this H. denticulatum complex has the extensive rhizomes of H. harperi, a specialization indicative of its aquatic habitat and an adaptation shared with its coinhabitants Rhynchospora careyana , Oxypolis canbyi , and Lobelia boykinii .^[1]

Description

Hypericum harperi is a rhizomatous herb with slender, pinkish rhizomes, with a branched base growing 0.3–1 m (1 ft 0 in – 3 ft 3 in) tall. The flowering branches are typically from median or upper stem nodes. The brown to reddish aerial stems are spongy and become green upward. The green primary stems have four lines and are covered with glandular dots. The internodes are 8–20 mm (0.31–0.79 in) long, about as long as the leaves. The sessile leaves are ascending and become deflexed when fading. The leaves are 10–30 mm (0.39–1.18 in) long and 3–5 mm (0.12–0.20 in) wide. The lanceolate leaves have a plane margin with an acute apex and a cuneate base. There are one to three basal veins and a midrib either unbranched or possessing a single branch. The laminar glands are dense but inconspicuous. The inflorescence possess up to about 30 flowers with flowering branches up to 16 lower nodes. The whole inflorescence is a pyramidal to subcorymbiform shape. The pedicels are 1.5–2 mm (0.059–0.079 in) long; the bracts are 2–6 mm (0.079–0.236 in) long. The star-shaped flowers are 4–10 mm (0.16–0.39 in) in diameter, with orange-yellow petals that number about twice the sepals. The sepals are 3–5 mm (0.12–0.20 in) long, with three to five veins. The sepals are typically unequal, lanceolate, and have linear glands that become punctiform distally. The 50 to 80 stamens are about 3–6 mm (0.12–0.24 in) long. The ovoid ovary is 1–1.5 mm (0.039–0.059 in) long with two to three styles ranging 2–4 mm (0.079–0.157 in) long. The seeds are 0.5 mm (0.020 in) long.^[2]

Habitat and distribution

Hypericum harperi grows in swamps as well as wet pine barrens, especially the shallows of depressional wetlands (Carolina bays). It rarely will occur in open, seasonal depressions. It grows in the coastal plain of South Carolina, Georgia, and northern Florida.^[2] It occurs at elevations between 0–200 m (0–656 ft).^[3] It occurs alongside Taxodium ascendens , Nyssa biflora , and other similar species.^[1]

Related Research Articles

Hypericum tetrapterum 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.

Hypericum mutilum is a species of St. John's wort known by the common name dwarf St. John's wort. It is native to parts of North America and is present in other parts as an introduced species. It is an annual or perennial herb taking a multibranched erect form up to about 60 centimeters tall. The oval green leaves are one or two centimeters long and are covered in tiny glands. The inflorescence is a compound cyme of tiny flowers. H. mutilum subsp. mutilum and subsp. boreale have a diploid number of 16, and H. mutilum subsp. boreale can have a diploid number of 18.

Hypericum terrae-firmae is a woody perennial flowering plant in the St. John's wort family Hypericaceae. It is an endemic plant species of Belize.

Hypericum annulatum is a species of flowering plant in the family Hypericaceae. It is a perennial herb of varying heights which grows upright, with more than a hundred flowers of a golden yellow color. First described in 1827, the species has a wide distribution from Eastern Europe to East Africa, and its appearance can vary greatly based on its geographic location. It has been used in Bulgarian folk medicine, and has more recently been investigated for its effectiveness in slowing the growth of or killing certain types of human cancer.

Hypericum boreale, also known as northern St. John's-wort, is a short-lived perennial species of flowering plant in the family Hypericaceae, section Trigynobrathys.

Hypericum cuisinii is a perennial herb in the genus Hypericum, in the section Adenosepalum. The herb has pale yellow flowers and occurs in Greece and Turkey.

Hypericum densiflorum, also known as bushy St. John's wort or dense St. John's wort, is a perennial herb in the flowering plant family Hypericaceae native to North America. The specific epithet densiflorum is Latin, meaning "densely flowered", referring to the many-flowered cymes.

Hypericum undulatum, the wavy St Johns Wort, is a herbaceous perennial flowering plant native to western Europe and northern Africa. The specific name undulatum is Latin, meaning "wavy" or "undulated", referring, just as the common name, to the wavy leaf margins of the herb. The plant has a diploid number of 16 or 32.

Hypericum edisonianum, known as Arcadian St. John's wort, Edison's St. John's wort, and Edison ascyrum, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is endemic to Florida.

Hypericum phellos is a species of shrub or small tree in Hypericumsect. Brathys. The species is found in Colombia and Venezuela on scrubby slopes and moist woods.

Hypericum denticulatum, the coppery St. John's Wort, is a perennial herb in the flowering plant family Hypericaceae. It is native to the Eastern United States. The species has two varieties, H. denticulatum var. recognitum and H. denticulatum var. acutifolium. The herb has a diploid number of 24 or 48.

Hypericum majus, the greater Canadian St. John's wort, is a perennial herb native to North America. The specific epithet majus means "larger". The plant has a diploid number of 16.

Hypericum humboldtianum is a species of shrubby flowering plant in the St. John's wort family Hypericaceae native to Colombia and Venezuela.

Hypericum myrtifolium, the myrtleleaf St. Johnswort, is a species of flowering plant in the St. John's wort family, Hypericaceae. It is endemic to the Southeastern United States. It was first described by Jean-Baptiste Lamarck in 1797.

Hypericum assamicum is a species of flowering plant in the St. John's wort family, Hypericaceae. It is endemic to India. Hypericum assamicum is one of two species of Hypericum in the section Hypericum sect. Sampsonia.

Hypericum aucheri, also known as Koramanotu in Turkish, is a herbaceous perennial flowering plant in the St. John's wort family Hypericaceae.

Hypericum coris, the heath-leaved St. John's wort, also called yellow coris, is a species of flowering plant in the family Hypericaceae, and is the type species of sect. Coridium. It is a low shrub, and it is found in Switzerland and northwestern Italy. The species has been a popular garden plant since the 18th century, valued for its long flowering period and for how well it adapts to cultivation.

Hypericum vacciniifolium is a species of flowering plant in the flowering plant family Hypericaceae. It was first described by August von Hayek and Walter Siehe in the Ann. K. K. Naturhist. Hofmus. journal in 1914 from a specimen collected by Siehe in 1912.

Hypericum heterophyllum is a flowering plant in the Hypericaceae family and is the only species in Hypericum sect. Heterophylla.

Hypericum elodeoides, commonly called the Himalayan St. John's Wort, is a species of flowering plant of the St. John's wort family (Hypericaceae).

References

1 2 3 James R. Allison (2011). "Synopsis of the Hypericum denticulatum Complex (Hypericaceae)". Castanea. Southern Appalachian Botanical Society. 76 (1): 99–115. doi:10.2179/10-009.1. ISSN 1938-4386. JSTOR 41301584. S2CID 85648010.
1 2 3 Norman K. B. Robson (1951). Studies in the genus Hypericum L. (Guttiferae) 8. Sections 29. Brathys (part 2) and 30. Trigynobrathys. Bulletin of the British Museum (Natural History). Vol. 1. British Museum (Natural History). pp. 67–68.
↑ "Hypericum harperi". Flora of North America. eFloras.org. Retrieved October 2, 2018.

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[synopsis-1] 1 2 3 James R. Allison (2011). "Synopsis of the Hypericum denticulatum Complex (Hypericaceae)". Castanea. Southern Appalachian Botanical Society. 76 (1): 99–115. doi:10.2179/10-009.1. ISSN 1938-4386. JSTOR 41301584. S2CID 85648010.

[Bulletin-2] 1 2 3 Norman K. B. Robson (1951). Studies in the genus Hypericum L. (Guttiferae) 8. Sections 29. Brathys (part 2) and 30. Trigynobrathys. Bulletin of the British Museum (Natural History). Vol. 1. British Museum (Natural History). pp. 67–68.

[eflora-3] "Hypericum harperi". Flora of North America. eFloras.org. Retrieved October 2, 2018.

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