Streptanthus is a genus of plants within the family Brassicaceae. There are about 35 known species within the genus Streptanthus, distributed mostly throughout western North America. The common names for this genus are twistflower and jewelflower. Twenty-four of the species and eleven lesser taxa occur in California, thirty-two of which are California endemics; seventeen of these California taxa are classified as rare plants.
Streptanthus niger is an endangered species within the family Brassicaceae. Like other genus members, this herb has wavy petal margins with perimeter calluses that discourage larval herbivory. This plant is endemic to the Tiburon Peninsula of Northern California, and occurs at elevations below 150 m on serpentine grasslands. The common name for this species is Tiburon jewelflower or black jewelflower. This annual herb blooms in May and June and displays dark purple sepals. The etymology of this genus scientific name derives from the Greek word streptanthus, meaning twisted flower, with reference to the notable wavy margins of the petals. The species name niger relates to the color of the seeds being black, although an alternate account cites the dark color of the petals as the source of the appellation.
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.
Streptanthus albidus is a species of flowering plant in the mustard family known by the common name Metcalf Canyon jewelflower. It is endemic to California, where it is known only from the Central Coast Ranges and San Francisco Bay Area. It grows in open areas such as grasslands, often on serpentine soils.
Streptanthus barbatus is a species of flowering plant in the mustard family known by the common name Pacific jewelflower. It is endemic to the southern Klamath Mountains of far northern California, where it occurs in open wooded habitat among Jeffrey Pines, generally on serpentine soils. It is a perennial herb producing a decumbent or erect, sometimes branching stem up to 70 to 90 centimeters long. It is hairless except for some light hairs on the flowers and the bases of the leaves. The largest leaves are at the base of the plant. They are oval with faintly toothed, bristly edges and borne on short petioles. Leaves above these are oval to rounded and may clasp the stem. Flowers occur at intervals along the upper stem. Each has a spherical to urn-shaped calyx of keeled sepals under a centimeter long with curving petals barely emerging from the tip. The calyx of sepals is whitish, darkening purple in maturity. The petals are purple. The fruit is a long, flat, curving silique which may be 7 centimeters in length.
Streptanthus barbiger is a species of flowering plant in the mustard family known by the common name bearded jewelflower. It is endemic to California, where it is limited to the North Coast Ranges. It grows in woodlands and chaparral habitat, often on serpentine soils. It is an annual herb producing a branching stem up to about 80 centimeters in maximum height. Leaves near the base of the stem are lance-shaped to oval and pointed, usually with toothed edges, the blades measuring up to 7 centimeters long. Leaves higher on the stem may be longer but are narrower and have smooth edges. Flowers occur at intervals along the upper stem. Each has a spherical to urn-shaped calyx of greenish yellow or purple sepals under a centimeter long. Whitish or purple-tinged petals up to a centimeter long emerge from the tip. The fruit is a long, flat, curving silique which may be 7 centimeters in length.
Streptanthus campestris is a species of flowering plant in the mustard family known by the common name southern jewelflower. It is native to southern California and northern Baja California, where it is known from fewer than 20 occurrences scattered between San Bernardino County, California, and Sierra de San Pedro Mártir in northern Baja. It grows in mountain chaparral, woodlands, and forests, at elevations up to 2300 meters. It is a perennial herb producing a thick, few-branched stem up to 1.5 meters tall or more. The basal leaves have fleshy oval blades with bristly, toothed edges which are borne on petioles. Leaves farther up the stem are lance-shaped with smooth or wavy edges and bases that clasp the stem. Flowers occur at intervals on the upper stem. Each has a bell-shaped calyx of bristle-lined purple sepals with four purple tipped yellow petals emerging from the tip. The fruit is a narrow, curving or straight silique which may reach 14 centimeters in length.
Streptanthus diversifolius is a species of flowering plant in the mustard family known by the common name variableleaf jewelflower, or varied-leaved jewelflower. It is endemic to California, where it is limited to the Sierra Nevada foothills. It is a resident of woodlands and other foothill habitat. It is an annual herb producing a hairless, waxy stem up to a meter tall. The basal leaves are variable in shape and are often divided into narrow, threadlike segments. Leaves higher on the stem are also variable, having round to lance-shaped blades which clasp the stem at their bases. Flowers occur at intervals along the upper stem, with one or two leaflike bracts at the base of the raceme. Each flower has an urn-shaped calyx of keeled sepals about half a centimeter long and white, yellowish, or purple in color, sometimes with white edging. White, purple-veined petals emerge from the tip. The fruit is a thin, flat, curving silique which may be 8 or 9 centimeters in length.
Streptanthus drepanoides is an uncommon species of flowering plant in the mustard family known by the common name sicklefruit jewelflower. It is endemic to California, where it is known from a scattered distribution throughout several mountain ranges in the northern part of the state, including the Klamath Mountains. It is a resident of chaparral and woodlands, generally on serpentine soils. It is an annual herb producing a mostly hairless, waxy stem up to 40 or 45 centimeters tall. The ephemeral basal leaves have round or oval blades, sometimes edged with teeth. Leaves higher on the stem have fleshy oval blades that clasp the stem, the lower ones each measuring up to 9 centimeters long by 7.5 wide. Flowers occur at intervals along the upper stem. Each has an urn-shaped calyx of greenish or yellowish sepals under a centimeter long with whitish or purplish, purple-veined petals emerging from the tip. The fruit is a straight or sickle-shaped curving silique up to 9 centimeters long.
Streptanthus fenestratus is an uncommon species of flowering plant in the mustard family known by the common name Tehipite Valley jewelflower.
Streptanthus glandulosus is a species of flowering plant in the mustard family known by the common name bristly jewelflower. It is native to California and southwestern Oregon, where it grows in many types of habitat, including grassland, chaparral, and woodlands. Genetic and other analyses indicate that it is a species complex with ten subspecies which evolved as populations were isolated from each other. The complex includes subspecies previously considered separate species, such as the rare Tiburon jewelflower endemic to the San Francisco Bay Area. Plants in the complex are variable. In general they are annual herbs growing 10 centimeters to over a meter in height. They may be hairless to hairy to bristly. The ephemeral basal leaves have blades borne on winged petioles. Leaves higher on the stem are linear to lance-shaped and clasp the stem at their bases. Flowers occur at intervals along the upper stem. Each flower has an urn-shaped calyx of sepals one half to over one centimeter long which can be most any color from white to yellowish to pink or purple to nearly black. Purple, white, or purple-veined white petals emerge from the tip. The fruit is a straight or curving silique up to 11 centimeters long.
Streptanthus howellii is an uncommon species of flowering plant in the mustard family known by the common name Howell's jewelflower. It is endemic to the Klamath Mountains of southern Oregon and northern California. It grows in mountain forests on serpentine soils. It is a perennial herb producing a hairless, often waxy-textured stem up to 70 or 80 centimeters in maximum length. It is generally unbranched. The ephemeral basal leaves have fleshy oval blades with smooth or toothed edges, borne on petioles. Leaves farther up the stem are similar but smaller and narrower, with shorter petioles or none. They do not clasp the stem. Flowers occur at intervals along the upper stem. Each has a calyx of purple sepals under a centimeter long with purple-tipped yellow petals emerging from the tip. The fruit is a thin, smooth, curved silique up to 12 centimeters long.
Streptanthus insignis is an uncommon species of flowering plant in the mustard family known by the common names plumed jewelflower and San Benito jewelflower. It is endemic to California, where it is known only from the Inner Central Coast Ranges. It grows in grassland and chaparral habitat, usually on serpentine soils. It is an annual herb producing a hairy, bristly, branching stem up to about 60 centimeters long. The lance-shaped basal leaves are borne on short petioles. Leaves midway up the stem are longer, and those near the top are shorter. They sometimes clasp the stem at their bases. Flowers occur at intervals along the upper stem. The uppermost flowers are often sterile and different in form. Each fertile flower has a bell-shaped calyx of sepals which is purple or greenish-yellow depending on subspecies. The petals at the tip are purplish or yellowish, also depending on subspecies. The fruit is a flat, straight silique which may be over 11 centimeters long.
Streptanthus morrisonii is an uncommon species of flowering plant in the mustard family known by the common name Morrison's jewelflower. It is endemic to California, where it is known from the North and Central Coast Ranges. It is limited to serpentine soils in chaparral and forest habitat. It is considered a species complex which includes Streptanthus brachiatus. S. morrisonii is divided into four subspecies and is variable. In general, it is a biennial herb producing a hairless, waxy stem up to 1.2 to 1.5 meters in maximum height, often branching at the tip. The basal leaves have fleshy, lance-shaped blades 3 to 5 centimeters long borne on petioles. The blades are gray-green on the upper surface and purple or purple-mottled underneath. Leaves higher on the stem are variable in shape and become smaller toward the top of the plant. Flowers occur at intervals along the upper stem. Each has an urn-shaped calyx of keeled sepals in shades of yellow-green to purple. The petals emerging from the tip are whitish with purple-brown veining. The fruit is a flattened straight or slightly curved silique up to 8 centimeters long.
Streptanthus oliganthus is an uncommon species of flowering plant in the mustard family known by the common name Masonic Mountain jewelflower. It is native to western Nevada and eastern California, where it grows in the rocky hills east of the central Sierra Nevada. Its habitat includes forest, woodland, sagebrush, and mountain talus. It is a rhizomatous perennial herb producing a hairless, waxy, usually unbranched stem up to about 40 or 50 centimeters in maximum height. The basal leaves have lance-shaped, smooth-edged blades up to 10 centimeters long borne on fuzzy to rough-haired petioles. Leaves higher on the stem have shorter blades which may clasp the stem at their bases. Flowers occur at intervals along the upper stem. Each has a bell-shaped calyx of purple sepals no more than a centimeter long. The petals emerging from the tip are reddish purple or purple-tipped. The fruit is a smooth, flat, straight or slightly curved silique up to 8 to 10 centimeters long.
Streptanthus tortuosus is a biennial or short lived perennial plant in the mustard family (Brassicaceae) known by the common names shieldplant, shieldleaf, and mountain jewelflower.
Streptanthus bracteatus is a species of flowering plant in the mustard family known by the common names bracted jewelflower and bracted twistflower. It is endemic to Texas in the United States.
Hypericum punctatum, the spotted St. John's wort, is a perennial herb native to North America. The yellow-flowered herb occurs throughout eastern North America into southern Canada. The process of microsporogenesis carried out by this plant is prone to errors in chromosomal segregation. It has a diploid number of 14 or 16. Insects are attracted to the plant's pollen and the hypericin in the plant's leaves is toxic to mammals.
Penstemon tenuis is a species of flowering plant in the plantain family known by the common name sharpsepal beardtongue. It is endemic to Texas, Louisiana, Mississippi, and Arkansas in the United States where it is found in open, damp areas in alluvial soil. It flowers from early April into early June.
Asclepias connivens is a species of milkweed, commonly called Baldwin's milkweed or the largeflower milkweed. It is an obligate wetland species, native to the southeastern United States.
