Does Ixora or Mesquite have more species?
Ixora
Title: Ixora
Passage: Ixora is a genus of flowering plants in the Rubiaceae family.  It is the only genus in the tribe Ixoreae.  It consists of tropical evergreen trees and shrubs and holds around 545 species.  Though native to the tropical and subtropical areas throughout the world, its centre of diversity is in Tropical Asia.  "Ixora" also grows commonly in subtropical climates in the United States, such as Florida where it is commonly known as "West Indian Jasmine".  Other common names include "viruchi", "rangan", "kheme", "ponna", "chann tanea", "techi", "pan", "siantan", "jarum-jarum/jejarum", "jungle flame", "jungle geranium" among others.  The plants possess leathery leaves, ranging from 3 to 6 inches in length, and produce large clusters of tiny flowers in the summer.  Members of Ixora prefer acidic soil, and are suitable choices for bonsai.  It is also a popular choice for hedges in parts of South East Asia.  In tropical climates they flower year round and are commonly used in Hindu worship, as well as in ayurveda and Indian folk medicine.
Title: Mesquite
Passage: Mesquite is the common name for the genus "Prosopis", containing over 40 species of small leguminous trees.  They are native to the southwestern United States and Mexico (even the creeping mesquite, which is invasive in southern California).
Title: Ambrosia cheiranthifolia
Passage: Ambrosia cheiranthifolia is a rare species of flowering plant known by the common names South Texas ambrosia and Rio Grande ragweed.  It is native to the coast of South Texas and the Mexican states of Tamaulipas and Coahuila.  It occurs in coastal prairie, grassland, and mesquite shrubland habitat.  It has declined because its native habitat has been cleared for development, with remaining open savanna invaded by non-native grasses such as buffelgrass ("Cenchrus ciliaris").  Today there are perhaps 20 populations remaining, but some of these may have very few genetic individuals because the species is clonal, with many cloned plants attached by one rhizome.  It is not certain that the plant still exists in Mexico.  This is a federally listed endangered species of the United States.
Ixora Mesquite