Wednesday 31 August 2016

Manihot pachycaulis: A new species of Cassava from Goiás State, Brazil.

Cassavas, Manihot spp., are a group of trees and shrubs in the Milkspurge family, Euphorbiaceae, which includes the widely cultivated Edible Cassava, Manihot esculenta. The genus is thought to have originated in Central America, but reaches its maximum diversity in the Cerrado (savanah), Caatinga (thornscrub), and Amazon (rainforest) ecosystems of Brazil, where about 80 of the 100 known species are found.

In a paper published in the Nordic Journal of Botany on 22 January 2016, Marcos José da Silva, Alexandre Antonio Alonso, and Rodolfo Carneiro Sodré of the Departamento de Botânica at the Universidade Federal de Goiás, describe a new species of Cassava from the Cerrado of Goiás State, Brazil.

The new species is named Manihot pachycaulis, where 'pachycaulis' means 'thick-stemmed'. The plants are dwarf shrubs reaching 15-45 cm in height, with pendant flowers and lobed leaves. The species was found growing on Cerrado Grasslands in the Chapada dos Veadeiros region of Goiás State, on hillslopes with clay or clay and rock soils, at altitudes of between 705 and 1028 m above sealevel.

Details of Manihot pachycaulis (A) general aspect of the plant, (B) flowering branch, (C) detail of the stem, note the enlarged base, (D) aspect of the inflorescence showing the staminate flower resupined, (E) detail of pistillate flowers. Marcos José da Silva in Da Silva et al. (2016).

All of the colonies of the plant discovered were within a 100  km2 area in an area without any conservation protection, and none of these colonies contained more than about 10 plants. For this reason the species is considered to be Vulnerable under the terms of the  International Union for the Conservation of Nature's Red List of Threatened Species.

See also...

http://sciencythoughts.blogspot.co.uk/2015/08/catasetum-telespirense-new-species-of.htmlCatasetum telespirense: A new species of epiphytic Orchid from the southern Brazilian Amazon.                                                                     In 2011-2012 a series of series of rescue expeditions recovered and relocated around 105 000 epiphytic plants (plants which live on other plants, typically...
http://sciencythoughts.blogspot.co.uk/2014/12/two-new-species-of-bigonia-from-brazil.htmlTwo new species of Bigonia from Brazil. Bigonias of the genus Tynanthus are lianas (woody climbers) found across the Neotropics (tropical areas of Central and South America), but reaching their maximum diversity in the wet forests of...
http://sciencythoughts.blogspot.co.uk/2013/04/two-new-species-of-milkvine-from.htmlTwo new species of Milkvine from Venezuela and Brazil.                                          Milkvines of the genus Malalea are found across southern parts of North America, Central America and northern South America. They are perennial twining vines, who get their common name from the milky...
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