Anatomy, Morphology, and Cladistic Analysis of Monsonia L. (Geraniaceae).

[摘要] Phylogenetip relationships among the 25 species of the old-world genusMonsoniaare explored by means of a cladistic analysis. After a detailed revision, 20 morphological and anatomical characters were selected, including some new ones from nectaries, androecium, and mericarps. Phylogenetic analysis yielded 9 most parsimonious trees. The strict consensus tree showed two major clades: one is formed by the 9 species ofMonsoniasect.Monsonia , characterised by plumose awns, plusSarcocaulon ; and a second with the 16 species ofMonsoniasect.Olopetalumwhich share the type of mericarp detaching, consistency of columella and the thick mericarp walls. Consequently, some doubts about the monophyly ofMonsoniaexists. However, the current infrageneric classification ofMonsoniais supported after transferringM. longipesandM. speciosato sect.Olopetalum . Several characters of the mericarp are related to zoochory, which seems to be a derived syndrome inMonsonia , as in the other Geraniaceae.

[学科分类] 植物学

[关键词] anatomy;morphology;cladistics;Monsonia;Geraniaceae