New taxa of Impatiens (Balsaminaceae) from Madagascar. IV

In a fourth paper as precursor to a revision of Balsaminaceae in Madagascar and the Comoro Islands, 11 species from subgenus Impatiens (I. bardotiae, I. barthlottii, I. ankaranensis, I. tsingycola, I. nicolliae, I. academiae-moguntiae, I. betsomangae, I. guillaumetii, I. nomenyae, I. nusbaumeri, and I. laurentii) and 18 species from subgenus Trimorphopetalum (I. georgei-schatzii, I. nosymangabensis, I. paranyi, I. haingosonii, I. mahalevonensis, I. ambahatrensis, I. messmerae, I. andapensis, I. fianarantsoae, I. carlsoniae, I. rakotomalazana, I. druartii, I. ampokafoensis, I. rapanarivoi, I. befiananensis, I. tsararavina, I. maevae, and I. razanatsoa-charlei) are described as new and illustrated.