Question: Which has more species, Erythrina or Thalia?
Context: Erythrina burttii is a flowering plant species in the genus of "Erythrina" found in Kenya and Ethiopia. Wiliwili, with the scientific name Erythrina sandwicensis, is a species of flowering tree in the pea family, Fabaceae that is endemic to the Hawaiian Islands.  It is the only species of "Erythrina" that naturally occurs there.  It is typically found in Hawaiian tropical dry forests on leeward island slopes up to an elevation of 600 m . Thalia is a genus of six currently recognized species found in aquatic or marshy habitats, ranging in Africa from Senegal to Sudan to Zimbabwe, and in the Americas from Illinois to Argentina.  Alligator-flag is a common name for plants in this genus.  The generic name is in honor of Johannes Thal (1542–1583), a German doctor who wrote a Flora of the Harz Mountains. Erythravine is a tetrahydroisoquinoline alkaloid found in the plant "Erythrina mulungu" and other species of the genus "Erythrina." Erythrina fusca is a species of flowering tree in the legume family, Fabaceae.  It is known by many common names, including purple coraltree, gallito, bois immortelle, bucayo, and the more ambiguous "bucare" and "coral bean".  "E. fusca" has the widest distribution of any "Erythrina" species; it is the only one found in both the New and Old World.  It grows on coasts and along rivers in tropical Asia, Oceania, the Mascarene Islands, Madagascar, Africa, and the Neotropics. Erythrina × bidwillii is the scientific name for two different cultivars produced from hybridising "Erythrina" species at Camden Park Estate, New South Wales, Australia, in the early 1840s by William Macarthur, one of the most active and influential horticulturists in Australia. Erythrina abyssinica is a tree species of the genus Erythrina belonging to the plant family of the Fabaceae (or Leguminosae) described by Augustin Pyramus de Candolle in 1825.  This leguminous tree species is native to East Africa , Eastern DRC and southern Africa. Erythrina velutina is a species of leguminous tree.  It is indigenous to Brazil, Peru, Ecuador, Colombia, Venezuela, and Hispaniola and has been introduced to much of the Caribbean, Uganda, and Sri Lanka.  It also occurs on the Galápagos Islands, but whether it is indigenous or introduced there is unclear.  In Brazil, it occurs on plains and near rivers in the arid parts of the northeast of the country and is commonly known as "mulungu".  "Erythrina velutina" grows as a large tree to around 10 m (30 ft) high and has short spines on the stem.  It is perennial. Erythrina herbacea, commonly known as the coral bean, Cherokee bean, Mamou plant in South Louisiana, red cardinal or cardinal spear, is a flowering shrub or small tree found throughout the southeastern United States and northeastern Mexico; it has also been reported from parts of Central America and, as an introduced species, from Pakistan.  Various other systematic names have been used for this plant in the past, including "Erythrina arborea", "Erythrina hederifolia", "Erythrina humilis", "Erythrina rubicunda", "Corallodendron herbaceum" and "Xyphanthus hederifolius". Erythrina is a genus of flowering plants in the pea family, Fabaceae.  It contains about 130 species, which are distributed in tropical and subtropical regions worldwide.  They are trees, growing up to 30 m in height.  The generic name is derived from the Greek word ερυθρóς ("erythros"), meaning "red," referring to the flower color of certain species.
Answer: Erythrina