Hypericum denticulatum

Last updated

Hypericum denticulatum
Hypericum denticulatum NRCS-2.jpg
Scientific classification Red Pencil Icon.png
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Eudicots
Clade: Rosids
Order: Malpighiales
Family: Hypericaceae
Genus: Hypericum
Section: H. sect. Trigynobrathys
Species:
H. denticulatum
Binomial name
Hypericum denticulatum
Synonyms [1] [2]

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.

Contents

Taxonomy

The most closely related species to Hypericum denticulatum is Hypericum rigidum var. sellowianum, a plant native to southeastern Brazil. The large disjunction in the distribution of the two herbs is most likely the result of ancient long distance dispersal.

The H. denticulatum complex has typically been treated as comprising two taxa, regarded in the past as separate species, two varieties, and most recently two subspecies. In 1948 Fernald and Schubert divided the species into three varieties, var. typicum (which became var. denticulatum), var. acutifolium, and var. recognitum. The last two varieties encompassed the former species Hypericum virgatum which had narrower leaves and sepals. In var. acutifolium they included specimens once described as Hypericum harperi . However, in 1980 Webb distinguished H. harperi by its morphology, ecology, and distinct distribution. Webb also confirmed reports of chromosome numbers n = 12 and 24 for H. denticulatum, showing that while n = 12 is found in varieties acutifolium and denticulatum as well as H. harperi, n = 24 is only found in var. denticulatum. Authors including Gleason, Cronquist, and Adams recognized var. acutifolium and var. recognitum as one variety, and the variety is now considered a subspecies (as is var. denticulatum). [3]

The specific epithet denticulatum means "small-toothed", referring to the marginal teeth on the petals. Walter named the species on account of the apiculate petals while Kunth named his H. denticulatum ( H. galinum ) in reference to the denticulate leaf margin of the species. In H. denticulatum subsp. acutifolium, the name acutifolium means "acutely leaved". In the former variety H. denticulatum var. recognitum, the name recognitum means "studied anew". [2] [3]

Description

Hypericum denticulatum is an erect perennial, typically glabrous throughout. The slender, herbaceous stems are strict or ascending, usually clumped together and arising from surculose bases. The four-angled, densely dotted stems reach 25–65 cm (9.8–25.6 in) in height and have four-lined internodes measuring 8–47 mm (0.31–1.85 in). The stems only branch at the typically aerenchymatous base and in the inflorescences. The nearly erect leaves are ovate, oval, or oboval, have acute tips, and are rounded at their sessile bases. The leaves are thick, leathery, and firm, the longest measuring 0.8–2.5 cm (0.31–0.98 in) in length and most measuring 0.6–1.7 cm (0.24–0.67 in) wide, most being shorter than the internodes. Typically leaves are planar but they can become recurved when dry. The leaves have one to five basal veins and are densely dotted. The terminal, pyramidal to corymbiform inflorescences bear up to 25 scattered racemose flowers on their ascending branches. The inflorescence is monochasial after the fourth grade, with lateral dichasial or monochasial branches six nodes below, the lateral branches bearing up to fifteen flowers. The pedicels are 2–4 mm (0.079–0.157 in) long and bracts are 3–6 mm (0.12–0.24 in) long. The star-shaped flowers are 5–13 mm (0.20–0.51 in) wide. The herbaceous sepals are oblong to narrowly ovate with acute apices, measuring 3–8 mm (0.12–0.31 in) long and 1.5–4 mm (0.059–0.157 in) wide. Each sepal has three to five veins. The petals are a coppery yellow, measuring 5–10 mm (0.20–0.39 in) long and 4–6 mm (0.16–0.24 in) wide. The 50 to 80 stamens are irregularly spaced, the longest measuring 3–5 mm (0.12–0.20 in). The ovoid ovary is 1.5–2 mm (0.059–0.079 in) long and 1–1.5 mm (0.039–0.059 in) wide. The singularly locular capsule is ovoid and held by the sepals. The three styles, measuring 2–4 mm (0.079–0.157 in) long, are distinct, short, and have capitate stigmas. [2] The ovoid capsules measure 3–5 mm (0.12–0.20 in) long and 2–3 mm (0.079–0.118 in) wide. The seeds are 0.4–0.7 mm (0.016–0.028 in) long. [4] [3]

H. denticulatum closely resembles Hypericum erythreae but can be distinguished by its shorter stems and more dense foliage. [5]

H. denticulatum subsp. denticulatum can be distinguished by its shorter stature, growing 0.2–0.7 m (7.9 in – 2 ft 3.6 in) tall, and by its lower internodes. Its appressed leaves are 2–20 mm (0.079–0.787 in) long and 5–15 mm (0.20–0.59 in) wide. Its sepals are 4–8 mm (0.16–0.31 in) long and 2–4 mm (0.079–0.157 in) wide. Its diploid number is 24 or 48. It can be found in moist ditches, pine barrens, and prairies at elevations between 0–400 m (0–1,312 ft). [3]

H. denticulatum subsp. acutifolium is taller than subsp. denticulatum, growing to 0.4–0.75 m (1 ft 4 in – 2 ft 6 in). Its leaves are 10–35 mm (0.39–1.38 in) long and 3–8 mm (0.12–0.31 in) wide. Its sepals are 3–3.5 mm (0.12–0.14 in) long and 1.5–2.5 mm (0.059–0.098 in) wide. Its petals tend to be more yellow and less orange than the other subspecies. It has a diploid number of 24. The subspecies occurs in dry roadsides, fields, and woodlands at elevations up to 700 m (2,300 ft) or possibly higher, with a less coastal distribution than the other subspecies. [3]

Distribution and habitat

Hypericum denticulatum grows in sandy or argillaceous shores, swamps, ditches, gravelly hills, and pine barrens at altitudes between 0–700 m (0–2,297 ft). [2]

The herb occurs in Alabama, Delaware, Georgia, New Jersey, New York, North Carolina, South Carolina, Pennsylvania, Tennessee, and Virginia, and rarely in Illinois as H. denticulatum var. recognitum. [4] [6]

Related Research Articles

<i>Hypericum socotranum</i> Species of flowering plant

Hypericum socotranum is a species of flowering plant in the Hypericaceae family which is endemic to the island of Socotra in Yemen. Its natural habitats are subtropical or tropical dry forests and rocky areas.

<i>Hypericum mutilum</i> Species of flowering plant in the St Johns wort family Hypericaceae

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.

<i>Pomaderris oraria</i> Species of shrub

Pomaderris oraria, commonly known as Bassian dogwood, is a species of flowering plant in the family Rhamnaceae and is endemic to south-eastern Australia. It is a compact shrub with hairy branchlets, hairy, elliptic leaves and panicles of hairy, greenish to cream-coloured or crimson-tinged flowers.

<i>Pomaderris paniculosa</i> Species of plant

Pomaderris paniculosa, commonly known as scurfy pomaderris, is a species of flowering plant in the family Rhamnaceae and is native to Australia and New Zealand. It is a shrub with hairy branchlets, round to elliptic or egg-shaped leaves with the narrower end towards the base and panicles of hairy, cream-coloured to greenish, sometimes crimson-tinged flowers.

<i>Prostanthera serpyllifolia</i> Species of plant

Prostanthera serpyllifolia, commonly known as small-leaved mint-bush, is a species of flowering plant in the family Lamiaceae and is endemic to southern Australia. It is a small shrub with small egg-shaped leaves and bright pink to red or metallic bluish-green flowers.

<i>Hypericum annulatum</i> Species of flowering plant in the St Johns wort family Hypericaceae

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.

<i>Boronia citriodora</i> Species of flowering plant

Boronia citriodora, commonly known as lemon-scented boronia, lemon plant or lemon thyme, is a woody shrub that is endemic to Tasmania. It has pinnate leaves and white to pink flowers that are arranged singly or in groups of up to seven, in the leaf axils or on the ends of the branches.

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.

<i>Hypericum canadense</i> Species of flowering plant in the St Johns wort family Hypericaceae

Hypericum canadense, known as Canadian St. Johns-wort, lesser St. John's wort, and lesser Canadian St. Johnswort, is a flowering plant in the genus Hypericum. It is a yellow-flowering annual or perennial herb native to North America and introduced to Ireland and The Netherlands. The specific epithet canadense means "Canadian".

<i>Hypericum undulatum</i> Species of flowering plant in the St Johns wort family Hypericaceae

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.

<i>Hypericum phellos</i> Species of flowering plant in the St Johns wort family Hypericaceae

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.

<i>Hypericum majus</i> Species of flowering plant

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.

<i>Hypericum humboldtianum</i> Species of flowering plant in the St Johns wort family Hypericaceae

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

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.

<i>Cyanothamnus inflexus</i> Species of flowering plant

Cyanothamnus inflexus is a plant in the citrus family Rutaceae and is endemic to tablelands near the New South Wales - Queensland border in Australia. It is an erect, woody shrub with pinnate leaves and up to seven white to pink four-petalled flowers in the leaf axils. Boronia bipinnata is similar but has larger, bipinnate or tripinnate leaves and smaller sepals and petals.

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.

<i>Hypericum heterophyllum</i> Species of flowering plant in the St Johns wort family Hypericaceae

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

<i>Triplarina volcanica</i> Species of flowering plant

Triplarina volcanica is a species of flowering plant in the myrtle family, Myrtaceae and is endemic to Queensland, where it is only found in three mountainous areas. It is a shrub with elliptical to egg-shaped leaves with the narrower end towards the base and flowers with five sepals, five white petals and fourteen to sixteen stamens.

<i>Hovea asperifolia</i> Species of legume

Hovea asperifolia is a species of flowering plant in the family Fabaceae and is endemic to south-eastern continental Australia. It is a shrub with hairy branchlets, narrowly oblong to narrowly linear leaves with stipules at the base, and mauve, pea-like flowers.

<i>Pomaderris betulina</i> Species of shrub

Pomaderris betulina, commonly known as birch pomaderris, is a species of flowering plant in the family Rhamnaceae and is endemic to south-eastern continental Australia. It is a shrub with hairy young stems, lance-shaped to oblong or elliptic leaves, and yellowish flowers.

References

  1. USDA, NRCS (n.d.). "Hypericum denticulatum". The PLANTS Database (plants.usda.gov). Greensboro, North Carolina: National Plant Data Team. Retrieved October 23, 2018.
  2. 1 2 3 4 Merrit Lyndon Fernald (1970). R. C. Rollins (ed.). Gray's Manual of Botany (Eighth (Centennial) - Illustrated ed.). D. Van Nostrand Company. pp. 1012–1013. ISBN   0-442-22250-5.
  3. 1 2 3 4 5 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. 64–66.
  4. 1 2 "Hypericum denticulatum". Flora of North America. eFloras.org. Retrieved October 23, 2018.
  5. Allison, James R. (2011). "Synopsis of the Hypericum denticulatum complex (Hypericaceae)". Castanea. Southern Appalachian Botanical Society. 76 (1): 99–115. doi:10.2179/10-009.1. S2CID   85648010.
  6. Robert H. Mohlenbrock, John Voigt (1974). A Flora of Southern Illinois (reprint ed.). SIU Press. p. 243. ISBN   9780809389896.