Question: Do both Butea and Calanthe have just two species?
Context: The wildebeests, also called gnus, are a genus of antelopes, scientific name Connochaetes.  They belong to the family Bovidae, which includes antelopes, cattle, goats, sheep and other even-toed horned ungulates. "Connochaetes" includes two species, both native to Africa: the black wildebeest, or white-tailed gnu ("C. gnou"); and the blue wildebeest, or brindled gnu ("C. taurinus").  Fossil records suggest these two species diverged about one million years ago, resulting in a northern and a southern species.  The blue wildebeest remained in its original range and changed very little from the ancestral species, while the black wildebeest changed more in order to adapt to its open grassland habitat in the south.  The most obvious way of telling the two species apart are the differences in their colouring and in the way their horns are oriented. The seepage salamander ("Desmognathus aeneus") is a small, terrestrial species of salamander in the family Plethodontidae.  It is endemic to the United States.  They are found in small areas of Tennessee, North Carolina, Georgia, and Alabama.  Its natural habitats are temperate forests, intermittent rivers, and freshwater springs.  It gets its name from the seepages around which it lives.  It is very similar in its appearance and life history to the pygmy salamander ("Desmognathus wrighti").  These two species differ greatly from the other "Desmognathus" species.  They are the smallest salamanders in the genus, measuring only 1 - in length.  They are also the only two terrestrial, direct-developing "Desmognathus" species.  However, the two species are not often seen to coexist, differing in distribution by elevation; although there are exceptions.  The seepage salamander is currently listed as Near Threatened, with its numbers declining in most of states in which it is found.  It is threatened by habitat loss, with logging having a major effect. The desert tortoises ("Gopherus agassizii" and "Gopherus morafkai" ) are two species of tortoise native to the Mojave and Sonoran Deserts of the southwestern United States and northwestern Mexico and the Sinaloan thornscrub of northwestern Mexico.  "G. agassizii" is distributed in western Arizona, southeastern California, southern Nevada, and southwestern Utah.  The specific name "agassizii" is in honor of Swiss-American zoologist Jean Louis Rodolphe Agassiz.  Recently, on the basis of DNA, geographic, and behavioral differences between desert tortoises east and west of the Colorado River, it was decided that two species of desert tortoises exist: Agassiz's desert tortoise ("Gopherus agassizii" ) and Morafka's desert tortoise ("Gopherus morafkai" ).  "G. morafkai" occurs east of the Colorado River in Arizona, as well as in the states of Sonora and Sinaloa, Mexico.  This species may be a composite of two species. Pangolins are mammals of the order Pholidota.  The one extant family, Manidae, has three genera: "Manis", which comprises four species living in Asia; "Phataginus", which comprises two species living in Africa; and "Smutsia", which comprises two species also living in Africa.  These species range in size from 30 to .  A number of extinct pangolin species are also known. Twenty-six amphibian species are found in Michigan, one of the fifty United States.  These species include twelve species of frog, twelve species of salamander and two species of toad, all members of the class Amphibia.  Blanchard's cricket frog, a subspecies of northern cricket frog, is considered to be threatened and two species, the marbled salamander and small-mouth salamander, are considered endangered; these are protected under the Endangered Species Act of the State of Michigan.  Two more species, the boreal chorus frog and lesser siren, are considered to be of special concern, although they are not protected under the act.  There are no amphibians native to Michigan that are included in the federal Endangered Species Act. Calanthe – commonly abbreviated Cal.  in horticulture – is a widespread genus of terrestrial orchids (family Orchidaceae) with some 200 species. Rhodacanthis is an extinct genus of Hawaiian honeycreeper.  All four species were endemic to the Hawaiian Islands.  Members of this genus were granivores, with bills adapted to the seeds and pods of legumes.  The two species that became extinct in the 1890s, "R. flaviceps" and "R. palmeri", inhabited upper elevation mesic forests dominated by koa "(Acacia koa") on the island of Hawaiʻ i.  Both were large birds; "R. flaviceps" measured 19 cm , while "R. palmeri" was 23 cm in length.  The combination of a giant bill with brightly colored plumage (yellow for "R. flaviceps", orange for "R. palmeri") gave the males a very striking appearance.  Koa seeds were the preferred food for the two species, but caterpillars were taken if necessary.  The two prehistoric species, "R. forfex" and "R. litotes", were denizens of more lowland tropical dry forests and shrublands on Kauaʻ i, Maui, and Oʻ ahu.  It is speculated that koaiʻ a ("Acacia koaia") was an important food source for both species, as their range did not overlap with that of koa.  Kanaloa ("Kanaloa" spp.)  pods and ʻ aʻ aliʻ i ("Dodonaea viscosa") berries were probably also eaten in addition to the occasional caterpillar. Engystomops freibergi is a frog native to the Amazonian Brazil, southeastern Peru, and Amazonian Bolivia.  For a while, it was considered to be a synonym of "Engystomops petersi", its sibling species, but its species status was resurrected in a study published in 1998.  Nevertheless, these two species have also been mixed in later studies, and there are records from the Guianas that have not yet been allocated to either species.  Divergence of these two species seems to have been driven by behavioural isolation related to male call characteristics more than geographic isolation. The Rugogastridae are a taxonomic family of flatworms that consist of a single genus, Rugogaster, with only two species.  The rugogastridae are parasites, and infect the rectal glands of various species of holocephalan fish.  The family, genus and two species are characterised by a single row of rugae (transverse thickenings of the body surface), numerous testes, and two caeca.  Species of the other three families of "Aspidogastrea" have a single caecum and either one or two testes. Butea is a genus of flowering plants belonging to the pea family, Fabaceae.  It is sometimes considered to have only two species, "B. monosperma" and "B. superba", or is expanded to include four or five species.
Answer: no