Are Wisteria and Helictotrichon both in the legume family?
no
Helictotrichon
Helictotrichon (alpine oatgrass) is a genus of perennial flowering plants in the grass family.
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 Genus name comes from the Greek heliktos meaning twisted and trichos meaning spine, referring to the shape of the awn.
Wisteria
Wisteria (also spelled Wistaria or Wysteria) is a genus of flowering plants in the legume family, Fabaceae (Leguminosae), that includes ten species of woody climbing vines native to the Eastern United States and to China, Korea, and Japan.
 Some species are popular ornamental plants.
 An aquatic flowering plant with the common name wisteria or 'water wisteria' is in fact "Hygrophila difformis", in the family Acanthaceae.
Xiphotheca
Xiphotheca is a genus of flowering plants in the legume family, Fabaceae.
 It belongs to the sub family Faboideae.
 The name of the genus is a compound of Ancient Greek ξίφος ("ksíphos"), which means "sword", and θήκη ("thēkē") which can mean "box" or "sheath"—a reference to the shape of the legume pods.
 Members of this genus can be distinguished by: Tadehagi triquetrum
The Trefle Gros, (Tadehagi triquetrum), is a species of flowering plant in the legume family, Fabaceae.
 It belongs to the sub family Faboideae.
 The species has two subspecies with the nominate one, but sometimes they given full species status by some authors.
 The maximum height of this shrub tree is 3m.
 Leaves alternate, linear-oblong, ovate with a tapering tip.
 Flowers show raceme inflorescence type, which are small, pale purplish in color.
 Fruit is a hairy legume.
 It is widespread in all South Asian, East Asian, and Southeast Asian countries. Aeschynomene rudis
Aeschynomene rudis is a species of flowering plant in the legume family known by the common name zigzag jointvetch.
 It is native to South America but it is known from other continents, including North America, as a noxious weed, especially of wet areas such as rice fields.
 It is aquatic or semi-aquatic, growing bristly, glandular stems near or in water.
 It grows up to two metres tall.
 The leaves are composed of oval-shaped leaflets each about a centimetre long.
 At the base of each leaf are large, flat, pointed stipules.
 The flower is purple-tinted white and 1 to 1.5 centimetres wide.
 The fruit is a lobed, gland-dotted legume pod narrowed between the seeds.
 It is up to 5 centimetres long and less than one wide.
 As the pod dries it breaks into segments, each segment containing a seed.
 The hard, shiny seed is kidney-shaped and 2 or 3 millimetres long. Senna armata
Senna armata is a species of flowering plant in the legume family known by the common names spiny senna and desert senna.
 It is native to the desert regions around the intersection of Nevada, Arizona, eastern California and northern Baja California, where it grows in sandy and rocky habitat, such as arroyos.
 It is a shrub growing up to a meter tall, its grooved, branching stems often narrowing to thorns at their tips.
 The spiny branches are coated in tubular hairs which help protect it from hot desert air.
 The spine-tipped leaves are each made up of two to four pairs of small leaflets.
 The leaves are ephemeral, dropping soon after emerging, leaving the shrub naked most of the time.
 Flowers occur singly or in small clusters in leaf axils.
 They are fragrant and showy, with five petals in shades of yellow to salmon pink, each measuring roughly a centimeter long.
 The fruit is a legume pod up to 4 centimeters long. Cassia (genus)
Cassia is a genus of flowering plants in the legume family, Fabaceae, and the subfamily Caesalpinioideae.
 Species are known commonly as cassias.
 Cassia is also the English common name of some species in the genus "Cinnamomum" of the family Lauraceae.
 Species of the genera "Senna" and "Chamaecrista" were previously included in "Cassia".
 "Cassia" now generally includes the largest species of the legume subtribe Cassiinae, usually mid-sized trees. Marina parryi
Marina parryi is a species of flowering plant in the legume family known by the common name Parry's false prairie-clover.
 It is native to the deserts of the southwestern United States and northern Mexico.
 This is a perennial herb producing stiff, branching stems 20 to 80 centimeters long.
 It is coated with glands and rough hairs.
 The leaves are made up of several pairs of small oval leaflets no more than 6 millimeters long.
 The inflorescence is a raceme of deep blue and white bicolored flowers each under a centimeter long.
 The fruit is a legume pod containing a single seed. Callerya
Callerya is a genus of flowering plants in the legume family, Fabaceae.
 It belongs to the subfamily Faboideae.
 Genetic analysis shows "Callerya" and "Wisteria" to be each other's closest relatives and quite distinct from other members of the tribe Millettieae.
 Both have eight chromosomes. Wisteria floribunda
Wisteria floribunda (common name Japanese wisteria) is a species of flowering plant in the pea family Fabaceae, native to Japan.
 Growing to 9 m , it is a woody, deciduous twining climber.
 It was brought from Japan to the United States in 1830's.
 Since then, it has become one of the most highly romanticized flowering garden plants.
 It is also a common subject for bonsai, along with "Wisteria sinensis" (Chinese wisteria).