Butia paraguayensis

Many researchers have considered it a dwarf variety of Butia yatay. In 1916 Odoardo Beccari reduced Cocos paraguayensis to a variety of Butia yatay, yet at the same time he described a new species from San Ignacio, Misiones, Argentina, which he named B. pungens. In 1970 Sidney Fredrick Glassman moved this species, along with all other Butia, to Syagrus, but in 1979 he changed his mind and moved everything back. In a 1979 review of the genus Butia by Glassman, he continued to distinguish B. pungens, A population of Butia palms in Paraguay once known as B. dyerana was considered a synonym of B. yatay by Glassman, but this population was reclassified as a synonym of B. paraguayensis by at least 1996, removing B. yatay from the flora of Paraguay. ==Distribution==

In Paraguay this species is very common; it occurs in the departments of Amambay, Caaguazú, Caazapá, Canindeyú, Concepción, Cordillera, Guairá, Misiones, Ñeembucú, and San Pedro. In Brazil it occurs in the states of Mato Grosso do Sul, Paraná, Rio Grande do Sul, and São Paulo. Bauermann et al. investigated the possibility of using palm pollen, including this species, in palynology, in order to try to provide more detail about the ancient changes in habitat in the state Rio Grande do Sul in Brazil by tracking the changes in distribution and abundance of the palms, but were unable to provide much detail on the subject. Habitat It grows in the cerrado (a type of savannah grassland) and pastures. It occurs on well-drained, usually sandy soils. In Rio Grande do Sul, Brazil, it is exclusively found growing on clayey (probably lateritic) soils. It grows from 100 to 300m in altitude. ==Description==

Butia paraguayensis is a short, always solitary-trunked palm usually forming a subterranean trunk -although great variability is shown with some specimens forming large trunks above ground up to 2m high. The 6 to 20 arched pinnate leaves Like all species of Butia studied, this species has relatively larger pollen grains than that of other genera of palm present in Rio Grande do Sul, Brazil. These grains are bilaterally symmetrical, oblate, monosulcate, and with the end piriform (pear-shaped). The surface is covered in minute 2μm-large reticulate patterns. The fruit are variable and may be shaped conical or ovoid, as well as being coloured green, purple, red, orange or yellow at maturity. The fruit are 3-4 x 2-3 cm, juicy, slightly fibrous, taste sweet-sour, with a persistent perianth base and 1-3 large nuts with homogeneous endosperm. Similar species It is often confused with (immature) Butia yatay. B. yatay always has a trunk, and is taller, with much larger leaves and inflorescences. In the past it was seen as a synonym of that species. ==Ecology==

It is well-adapted to the periodic wildfires of the cerrado. In Paraguay the fruit are a favourite food of the maned wolf, which may be an important seed disperser. Parrots and macaws also make use of the ripe fruit. ==Uses==

In Paraguay the fruit and palm hearts are eaten by local tribal communities (Ava Chiripá, Aché, others). The leaves are also used to make hats and other handicrafts. The unripe, green fruit are believed to be useful for combating intestinal worms. The fruit are not considered edible in Argentina. It is advised to plant the palms in full sunlight. It is said to take −11 °C, but should be protected at −4 °C in the Netherlands. ==Conservation==

In Uruguay this species is now very rare (175 plants on a single hill) due to habitat loss due to agricultural activities such as cattle ranching and forestry (pulpwood plantations of eucalyptus). Sheep and cattle eat the seedlings, preventing recruitment. As of 2017, like all four species of Butia native to Uruguay, it is protected by law. Adult palms may not be felled or moved without government permission. ==References==