Hesperolinon is a genus in the family Linaceae, whose common genus names are dwarf-flax or western flax, in reference to their distribution along the west coast of North America.
 There are 13 known species within this genus of wildflowers, most of which are limited to serpentine soil habitats within California, United States.
 These annual plants are thought to be mostly self-pollinating.
Mediaster is a genus of starfish in the family Goniasteridae.
 It was circumscribed in 1857 by William Stimpson for "M. aequalis", the genus's type species.
 Its junior synonym is the genus "Isaster", which was circumscribed in 1894 by Addison Emery Verrill for the species now known as "M. bairdi".
 Verrill himself synonymized the two genus names in 1899.
Monardella stebbinsii is a rare species of flowering plant in the mint family known by the common names Feather River monardella and Stebbins' monardella.
 It is endemic to Plumas County, California, where it is known from only about ten occurrences along the North Fork of the Feather River in the High Sierra.
 It is a member of the serpentine soils flora in rocky mountain habitat.
Silvestrosaurus is an extinct aquatic genus of lariosaurine nothosaurid sauropterygian known from the Middle Triassic (Anisian-Ladinian boundary) of Monte San Giorgio, southern Switzerland.
 It contains a single species, Silvestrosaurus buzzii, originally considered to be a species of the closely related "Lariosaurus".
 The species was named by Tschanz in 1989, based solely on the holotype PIMUZ T/2804 comprising the skull, the lower jaw, and a dis-articulated partial postcranial skeleton. "
Cyamodus hildegardis" tooth bearing elements were found in the stomach region of the specimen.
 The holotype was collected at Punkt 902 of Monte San Giorgio, from layer 97 of the Grenzbitumen zone, dating to the Anisian-Ladinian boundary of the Middle Triassic.
 Kuhn-Schnyner (1990) reassigned the species to its own genus, creating the combination "S. buzzii".
 The generic name honors a church near the collection locality of the holotype, dedicated to Saint Sylvester, a Pope during the reign of Constantine the Great, and from Greek "saurus", meaning "lizard", a common suffix for genus names of extinct reptile.
Monardella hypoleuca is a species of flowering plant in the mint family, known by the common names thickleaf monardella and white leaf monardella.
Monardella is a genus of approximately 40 species of annual and perennial plants native to western North America from British Columbia to northwestern Mexico.
 They are grown for their highly aromatic foliage, which in some species is used for herbal teas.
 The two-lipped, tubular flowers are formed in terminal clusters and are most usually red, pink, or purple.
Hoodia (known locally as "ghaap" or "bobbejaanghaap") is a genus of flowering plants in the family Apocynaceae, under the subfamily Asclepiadoideae, native to Southern Africa.
Monardella exilis, with the common names Mojave monardella and desert monardella, is an annual plant in the "Monardella" genus of the mint family (Lamiaceae).
Monardella purpurea is a species of flowering plant in the mint family known by the common names Siskiyou monardella and serpentine monardella.
Monardella lanceolata is a species of flowering plant in the mint family known by the common names mustang mint and mustang monardella.
 It is native to the mountains of California and Baja California, where it grows in chaparral, woodland, rocky slopes, and often disturbed habitat types.

Question: Are Hoodia and Monardella both plant genus names?
Answer: yes