Question: Which genus of flowering plants has the most species, Caesalpinia or Achimenes?

Passages:
Caesalpinia is a genus of flowering plants in the legume family, Fabaceae.  Historically, membership within the genus has been highly variable, with different publications including anywhere from 70 to 165 species, depending largely on the inclusion or exclusion of species alternately listed under genera such as "Hoffmannseggia".  It contains tropical or subtropical woody plants.  The generic name honors the botanist, physician, and philosopher Andrea Cesalpino (1519–1603). Psychotria is a genus of flowering plants in the Rubiaceae family.  It contains around 1,850 species and is therefore one of the largest genera of flowering plants.  The genus has a pantropical distribution and members of the genus are small understorey trees in tropical forests.  Some species are endangered or facing extinction due to deforestation, especially species of central Africa and the Pacific. Cyrtandra is a genus of flowering plants containing about 600 species, with more being discovered often, and is thus the largest genus in the family Gesneriaceae.  These plants are native to Southeast Asia, Australia, and the Pacific Islands, with the centre of diversity in Southeast Asia and the Malesian region.  The genus is common, but many species within it are very rare, localized, endangered endemic plants.  The species can be difficult to identify because they are highly polymorphic and because they readily hybridize with each other.  The plants may be small herbs, vines, shrubs, epiphytes, or trees.  The genus is characterized in part by having two stamens, and most species have white flowers, with a few red-, orange-, yellow- and pink-flowered species known.  Almost all species live in rainforest habitats. Austrobaileyales is an order of flowering plants, consisting of about 100 species of woody plants growing as trees, shrubs and lianas.  Perhaps the most familiar species is "Illicium verum", from which comes the spice star anise.  The order belongs to the group of basal angiosperms, the ANA grade, which diverged earlier from the remaining flowering plants, and, as such, it is the extant group after the Amborellales and Nymphaeales, that is sister to all remaining extant angiosperms outside of the ANA grade.  The order includes just three families of flowering plants, the Austrobaileyaceae, a monotypic family containing the sole genus, "Austrobaileya scandens", a woody liana, the Schisandraceae, a family of trees, shrubs, or lianas containing essential oils, and the Trimeniaceae, essential oil-bearing trees and lianas. Zeltnera is a genus of flowering plants in the gentian family.  It was erected in 2004 when the genus "Centaurium" (the centauries) was split.  Genetic analysis revealed that "Centaurium" was polyphyletic, made up of plants that could be grouped into four clades. Each became a genus.  "Centaurium" remained, but it is now limited to the Eurasian species.  The Mexican species now belong to genus "Gyrandra", and the Mediterranean and Australian plants are in genus "Schenkia".  The new name "Zeltnera" was given to this genus, which contains most of the North American centauries.  There are about 25 species. Echinacea is a genus, or group of herbaceous flowering plants in the daisy family.  The "Echinacea" genus has nine species, which are commonly called purple coneflowers.  They are found only in eastern and central North America, where they are found growing in moist to dry prairies and open wooded areas.  They have large, showy heads of composite flowers, blooming from early to late summer.  The generic name is derived from the Greek word ἐχῖνος ("ekhinos"), meaning "hedgehog," due to the spiny central disk.  These flowering plants and their parts have different uses.  Some species are cultivated in gardens for their showy flowers.  "Echinacea purpurea" is used in folk medicine.  Two of the species, "E. tennesseensis" and "E. laevigata", are listed in the United States as endangered species. Achimenes is a genus of about 25 species of tropical and subtropical rhizomatous perennial herbs in the flowering plant family Gesneriaceae.  They have a multitude of common names such as magic flowers, widow's tears, Cupid's bower, or hot water plant. Eriocaulon is a genus of about 400 species commonly known as pipeworts, of monocotyledonous flowering plants in the family Eriocaulaceae.  The genus is widely distributed, with the centers of diversity for the group occurring in tropical regions, particularly southern Asia and the Americas.  A few species extend to temperate regions, with ca. 10 species in the United States, mostly in the southern states from California to Florida, and only two species in Canada; China has 35 species, also mostly southern.  Only one species ("E. aquaticum") occurs in Europe, where it is confined to the Atlantic Ocean coasts of Scotland and Ireland; this species also occurs in eastern North America and is thought to be a relatively recent natural colonist in Europe.  In the Americas, "Eriocaulon" is the only genus in its family that occurs north of Florida.  They tend to be associated with wet soils, many growing in shallow water, in wetlands, or in wet savannas like flatwoods.  In wet soils, their abundance appears to be related to water levels, fire frequency, and competition from other plants such as grasses.  Experiments have shown that they are weak competitors compared to many other wetland plant species.  Some species can persist as buried seeds during unfavorable conditions.  The scientific name is derived from Ancient Greek εριον, "erion", meaning 'wool', and καυλός, "caulos", meaning 'stalk'. Sudamerlycaste is a genus of flowering plants in the Orchidaceae family.  It consists of approximately 45 species.  The genus was split off from "Lycaste" in 2002 by Fredy Archila.  Species in "Lycaste" that were endemic to South America and the Caribbean Islands were placed into the new genus "Sudamerlycaste" and those found in Mexico and Central America stayed in "Lycaste".  As a result of this change most of the species previously found in the "Lycaste" section "Fimbriatae" were then moved to the genus "Sudamerlycaste".  Species are either epiphytes or terrestrial.  In 2003 Henry Oakeley and Angela Ryan published the genus name "Ida" to accommodate South American and Caribbean plants previously placed in "Lycaste".  Their description included the type species of "Sudamerlycaste", "Lycaste andreettae".  This renders "Ida" an illegitimate name. Magnolia virginiana, most commonly known as sweetbay magnolia, or merely sweetbay (also laurel magnolia, swampbay, swamp magnolia, whitebay, or beaver tree), is a member of the magnolia family, Magnoliaceae.  It was the first magnolia to be scientifically described under modern rules of botanical nomenclature, and is the type species of the genus "Magnolia"; as "Magnolia" is also the type genus of all flowering plants (magnoliophytes), this species in a sense typifies all flowering plants.

Supporting sentences:
 Historically, membership within the genus has been highly variable, with different publications including anywhere from 70 to 165 species, depending largely on the inclusion or exclusion of species alternately listed under genera such as "Hoffmannseggia". Achimenes is a genus of about 25 species of tropical and subtropical rhizomatous perennial herbs in the flowering plant family Gesneriaceae.