Chamaesyce is a subgenus of plants in the family Euphorbiaceae. Recent phylogenetic studies have shown that Chamaesyce is deeply nested within the broader Euphorbia. Specifically, Chamaesyce is very closely related to plants like Euphorbia pulcherrima, the popular poinsettia. Currently, all species have now been reclassified as species of Euphorbia. Specifically, this group now belongs to Euphorbia subgenus Chamaesyce section Anisophyllum. Taxonomically speaking, Chamaesyce is considered a synonym of Euphorbia.
Euphorbia albomarginata, whitemargin sandmat or rattlesnake weed, is a small low-growing perennial, in the spurge family native to desert, chaparral, and grassland habitats of southwestern North America, from southern and central California to Northern Mexico and Louisiana.
Euphorbia maculata, known as spotted spurge, prostrate spurge, milk purslane, or spotted sandmat, is a fast-growing annual plant in the family Euphorbiaceae. While it is native to North America, where it is a common garden and lawn weed in the United States, it has become a common introduced species throughout the world, including Europe, Japan, Korea, Australia, and New Zealand.
Euphorbia polycarpa is a species of spurge known by the common name smallseed sandmat. It is native to the southwestern United States and northern Mexico, especially the deserts and other dry, sandy areas. This is a perennial herb producing stems that trail along the ground to form a clump or mat, sometimes growing somewhat upright. The leaves are each under a centimeter long. They are round or oval-shaped and have triangular stipules at the bases. What looks like a single flower is actually an inflorescence of many staminate (male) flowers united around a single central pistillate (female) flower. Bracts surrounding the flower unit are white and petal-like. The fruit is a thin spherical capsule less than 2 millimeters wide layered over a seed.
Euphorbia fendleri is a species of Euphorbia known by the common name Fendler's sandmat. It is native to much of the southwestern and central United States and northern Mexico, where it grows in scrub and woodland habitat in desert and plateau regions. This is a mat- or clump-forming reddish-green plant with a crooked, creeping, hairless stem. The leaves are rounded, oval, or spade-shaped, smooth along the edges and generally coming to a point, and not much more than one centimeter in maximum length. The tiny inflorescence is a cyathium with white-edged, scalloped appendages surrounding the actual flowers. There is a ring of 25 to 35 staminate flowers around one pistillate flower. The ovary of the pistillate flower enlarges into a lobed fruit about 2 millimeters long.
Euphorbia hooveri is a species of euphorb known by the common names Hoover's sandmat and Hoover's spurge. It is endemic to California, where it grows in the rare vernal pools of the Central Valley. Due to the elimination of most of its habitat, it became a federally listed threatened species in 1997.
Euphorbia melanadenia is a species of Euphorbia known by the common name red-gland spurge. It is native to the deserts and mountains of Baja California and southern California and Arizona, where it grows in dry, rocky habitat. It is a perennial herb forming a small clump or mat of very slender, tangling red stems. The stems are lined with pairs of slightly woolly oval-shaped leaves 2 to 9 millimeters wide. The tiny inflorescence is a cyathium less than 2 millimeters wide. The cyathium is a bell-shaped array of white, scalloped petal-like appendages surrounding the actual flowers. Each appendage has at its base a shiny red nectar gland. At the center of the appendages is a ring of male staminate flowers around a single female flower. The female flower develops into an oval-shaped fruit which bears wrinkled white seeds.
Euphorbia micromera is a species of flowering plant in the family Euphorbiaceae. It is known by the common name Sonoran sandmat. It is native to the southwestern United States from California to Texas, and northern Mexico, where it grows in sandy soils in desert and other dry habitat. It is an annual herb forming a small mat of slender stems. The hairy to hairless leaves are oblong in shape and just a few millimeters long. The tiny inflorescence is a cyathium less than a millimeter wide. It lacks the appendages that many similar species have in their cyathia. It has only a central female flower and 2 to 5 male flowers surrounded by round red nectar glands. The fruit is a minute round capsule.
Euphorbia nutans is a species of Euphorbia known by the common names eyebane and nodding spurge. It is native to much of the United States, Eastern Canada, Mexico, Central America, the Caribbean, and Venezuela.
Euphorbia parishii, known by the common name Parish's sandmat, is a species of euphorb. It is native to the sandy soils of the deserts in California and Nevada. It is a perennial herb forming a small patch on the ground. The slender, hairless, tangling stems have pairs of tiny, pointed oval leaves, each leaf just a few millimeters long. The minute inflorescence is a cyathium one millimeter wide. It is made up of several rounded nectar glands in shades of yellow to deep red surrounding many tiny male flowers and one female flower. The latter develops into a spherical fruit two millimeters wide.
Euphorbia prostrata is a species of spurge known by the common name prostrate spurge or prostrate sandmat.
Euphorbia revoluta is a species of euphorb known by the common name threadstem sandmat. It is native to Mexico and the southwestern United States from California to the Rocky Mountains. It is an annual herb producing thin, erect stems with pairs of linear leaves, each leaf up to 2.6 centimeters long. The inflorescence is a cyathium with rounded nectar glands surrounding one female flower and several male flowers. There are sometimes white petal-like appendages as well. The Navajo used this plant as a skin lotion.
Euphorbia serpens is a species of Euphorbia known by the common name matted sandmat. It is native to South America but it can be found on most continents as an introduced species and often a weed. This is an annual herb forming a mat of prostrate stems which root at nodes where the stem comes in contact with the ground. The oval leaves occur in oppositely arranged pairs, each leaf less than a centimeter long. The inflorescence is a cyathium with scalloped white petal-like appendages surrounding the actual flowers. A red nectar gland is at the base of each appendage, and at the center of the cyathium are several male flowers around one female flower. The fruit is a lobed, spherical capsule.
Euphorbia serpyllifolia is a species of euphorb known by the common names thymeleaf sandmat or thyme-leafed spurge. It is native to a large part of North America from Canada to Mexico, where it is a common member of the flora in many types of habitat. This is an annual herb growing as a prostrate mat or taking a somewhat erect form. The oblong leaves are up to about 1.5 centimeters long, sometimes hairy and finely toothed along the edges. The tiny inflorescence is a cyathium about a millimeter wide. It bears scalloped white petal-like appendages arranged around the actual flowers. At the center are several male flowers and one female flower, which develops into a lobed, oval fruit up to 2 millimeters wide. This plant had a number of traditional medicinal uses for many Native American groups.
Euphorbia setiloba is a species of euphorb known by the common name Yuma sandmat. It is native to the southwestern United States and northern Mexico, where it grows in dry habitat. This is a small, clumping annual herb with slender stems lined with pairs of tiny hairy leaves. Each leaf is just a few millimeters long and oval in shape with a bluntly pointed tip. The minute inflorescence is a cyathium less than two millimeters wide. It has distinctive appendages which are white with a few narrow, sharp-pointed lobes. There is a red nectar gland at the base of each. At the center of the appendages are the actual flowers, one female and several male. The ovary of the female flower develops into a hairy, spherical fruit about a millimeter wide.
Euphorbia balsamifera is a flowering plant in the spurge family Euphorbiaceae. It is distributed in the Canary Islands and the western Sahara. It is the vegetable symbol of the island of Lanzarote. Euphorbia adenensis has been treated as a subspecies of this species.
Euphorbia eleanoriae is a rare species of flowering plant in the euphorb family known by the common name Nā Pali sandmat. It is endemic to Kauaʻi, Hawaii. Like other native Hawaiian euphorbs it is called ʻakoko locally. This plant was only discovered in 1992 and described to science in 1996 as Chamaesyce eleanoriae. At that time there were fewer than 500 plants known, all occurring in small populations scattered across the sheer cliffs along the Nā Pali Coast of Kauaʻi. By 2001 the total population had already dropped; only three populations were found, for a total of fewer than 50 plants. The plant was federally listed as an endangered species of the United States in 2010.
Euphorbia missurica, commonly called prairie sandmat, or Missouri spurge, is a species of flowering plant in the spurge family (Euphorbiaceae). It is native to North America, where it is found primarily in area of the Great Plains. Its natural habitat is in dry, often calcareous areas, including glades, bluffs, and open woodlands.
Euphorbia angusta is a species in the Euphorbiaceae (spurge) family with the common name blackfoot sandmat. It is native to central and south Texas and northern Mexico.
