Question: Are both Huntleya and Cyrtostachys native to South America?

Context paragraphs:
Sparassodonta: Sparassodonta is an extinct order of carnivorous metatherian mammals native to South America.  They were once considered to be true marsupials, but are now thought to be either a sister taxon to them, or considerably distantly related, part of a separate clade of Gondwanan metatherians.  A number of these mammalian predators closely resemble placental predators that evolved separately on other continents, and are cited frequently as examples of convergent evolution.  They were first described by Florentino Ameghino, from fossils found in the Santa Cruz beds of Patagonia.  Sparassodonts were present throughout South America's long period of "splendid isolation" during the Cenozoic; during this time they shared the niches for large warm-blooded predators with the flightless terror birds. Previously, it was thought that these mammals died out in the face of competition from "more competitive" placental carnivorans during the Pliocene Great American Interchange, but more recent research has showed that sparassodonts died out long before eutherian carnivores arrived in South America (aside from procyonids).

Arapaima: The arapaima, pirarucu, or paiche are any large species of bonytongue in the genus Arapaima native to the Amazon and Essequibo basins of South America.  Genus "Arapaima" is the type genus of the family Arapaimidae.  They are among the world's largest freshwater fish, reaching as much as 3 m .  They are an important food fish.  They have declined in the native range due to overfishing and habitat loss.  In contrast, arapaima have been introduced to several tropical regions outside the native range (within South America and elsewhere) where they are sometimes considered invasive species.  Its local name, "pirarucu", derives from the indigenous words for "pira" meaning "fish" and "urucum" meaning "red".

Galictis: A grison, also known as a South American wolverine, is any mustelid in the genus Galictis.  Native to Central and South America, the genus contains two extant species: the greater grison ("Galictis vittata"), which is found widely in South America, through Central America to southern Mexico; and the lesser grison ("Galictis cuja"), which is restricted to the southern half of South America.  In Spanish it is referred to as a "huroncito" (literally "little ferret") or "grisón" and in Portuguese as a "furão".

Invasive species in South America: Invasive species are a serious threat to the native biodiversity of South America and are an ongoing cost to South American agriculture.  South America is an important region for the worlds biodiversity, and includes a wide variety of native species, many of which provide .  Introduced species in South America, have the potential to pose harm to ecosystems of the region and the aforementioned biodiversity.  Although many of these non-native species are invasive, residents of the region often value these species, making it more difficult to organize efforts to get rid of them.  Because of the instrumental and cultural value placed on these species, greater awareness, research, and policy are all necessary steps in solving invasive issues in South America.  Here is a list of just a few of the species that have invaded South America and where they originate.

Cyrtostachys: Cyrtostachys is a genus of flowering plant in the Arecaceae (palms) family.  Its species are found in southeast Asia, New Guinea, and in some of the and island habitats of the Oceania ecozone.

Yellow-chevroned parakeet: The yellow-chevroned parakeet ("Brotogeris chiriri"), is native to tropical South America south of the Amazon River basin from central Brazil to southern Bolivia, Paraguay and northern Argentina.  Caged birds have been released in some areas and the birds have established self-sustaining populations in the Los Angeles, San Francisco, California and Miami, Florida areas of the United States.  This bird seems to be doing better in its North American feral population than its closely related cousin, the white-winged parakeet.  The species is also fairily established in the downtown area of Rio de Janeiro, Brazil, where it was introduced.  The native population in South America continues to do well.

List of South American mammals: This is a list of the native wild mammal species recorded in South America.  South America's terrestrial mammals fall into three distinct groups.  The marsupials and xenarthrans are 'old-timers', their ancestors having been present on the continent since at least the very early Cenozoic Era.  During the early Cenozoic, South America's only land connection was to Antarctica, so it was effectively cut off from most of the world; as the fragments of Gondwana continued to separate, this connection was lost, leaving South America an island continent.  Caviomorph rodents and monkeys arrived as 'waif dispersers' by rafting across the Atlantic from Africa in the Eocene epoch, 35 million or more years ago.  All the remaining nonflying mammals of South America are recent arrivals, having migrated from North America via Central America during the past seven million years as part of the Great American Interchange; this invasion, which peaked around three million years ago, was made possible when the formation of the volcanic Isthmus of Panama bridged North and South America.  The newcomers out-competed and drove to extinction many unique mammals that had evolved during South America's long period of isolation, as well as some species from other classes (e.g., terror birds).

Huntleya: Huntleya is a small orchid genus native to South America, Central America and Trinidad.

Alternanthera philoxeroides: Alternanthera philoxeroides, commonly referred to as alligator weed, is a native species to the temperate regions of South America, which includes Argentina, Brazil, Paraguay and Uruguay.  Argentina alone, hosts around 27 species that fall within the range of the genus Alternanthera.  Its geographic range once used to cover only the Parana River region of South America, but it has since expanded to cover over 30 countries, such as the United States, New Zealand, China and many more.  This invasive species is believed to have been accidentally introduced to these non-native regions through sediments trapped/attached to tanks and cargo of ships travelling from South America to these various areas.

Nops (spider): Nops is a genus of medium-sized caponiid spider native to South America, Central America, and the Caribbean islands.  The genus currently counts 27 extant species plus one fossil in Dominican amber, but probably the real number of extant species is greater.  "Nops" have a great richness on the Caribbean islands (14 species).  Even species of Central America (4) and South America (15) are located in high proportion toward the area of the Caribbean Sea.  Most species of South America are known only from the coast of Colombia and Venezuela, including the islands of Aruba, Curaçao, Bonaire and Trinidad.  The genus is not revised yet, but apparently have a Neotropical distribution.

Supporting paragraphs: Huntleya Cyrtostachys
Answer: no