Changes of flora-information over time: Examples from Ethiopia and Eritrea and the Nordic countries

Abstract

Changes in Flora-information over time can be divided into three different categories: (1) “Real changes” (species enter the region by natural dispersal or become extinct). (2) “Floristic changes” (species known from elsewhere are discovered). (3) “Taxonomic changes” (species are discovered and described, taxonomic revisions change the status of previously known species). The Linnaean taxonomic methods for describing and naming plant species, which we still use today in a refined form, were developed in the middle of the 18th century. The Nordic flora was one of the first that was subjected to the Linnaean methods, but these methods were also applied to the flora of Ethiopia and Eritrea before the end of the 18^th century. An intensive activity involving floristic and taxonomic changes took place in Ethiopia and Eritrea in the 19^th century, particularly before ca. 1850, after which a period with a more steady level of activities followed. The Ethiopian Flora Project, which has been active between 1980 and 2009, has resulted in more than 470 species being described as new during the period, and more than 440 species described from elsewhere have been discovered to occur inside the Flora area. Recent studies of the Orchidaceae family in Scandinavia has demonstrated considerable changes in our information about that family in Scandinavia during the last 50 years, both real, floristic and taxonomic changes. Similar, or even greater, changes are to be expected in the flora of Ethiopia and Eritrea in the future.

Key words/phrases: Ethiopia, Eritrea, Floristic changes, Floristic exploration, Taxonomic changes