Polyphylétisme des campanules annuelles

Abstract

Les campanules annuelles, extrêmement complexes (6 sous-genres), sont d'origine polyphylétique. L'auteur montre que des lignées différentes ont pris naissance, soit par dysploïdie, de type descendant, accompagnée parfois de polyploïdie, soit à partir d'espèces vivaces avec lesquelles elles présentent de réelles affinités (dans ce cas, les annuelles ont le même nombre chromosomique ou un nombre dérivé de celui des espèces vivaces). Enfin, certaines annuelles forment avec des taxons vivaces et bisannuels de grands complexes d'espèces fortement apparentées entre elles.Summary.· The annual and very complexe Campanulo (6 subgenera) have a polyphyletic origin. The author shows that they are originated either by a decreasing dysploidy, sometimes accompagned with polyploidy, either from perennial species with which, they present a great resemblance (in this case, annuals have the same chromosome number or a derivated number of the perennial one). At last, sorne annuals form with perennial and bisannual taxa great complexes of related species.

How to Handle Speciose Clades? Mass Taxon-Sampling as a Strategy towards Illuminating the Natural History of Campanula (Campanuloideae)

“…High levels of extinction could potentially explain the current disjunct distribution of C. fastigiata in both western and eastern Mediterranean regions. Finally, the present clade also supports a new switch from the annual to perennial condition, a rather common episode in Campanula evolution [82] the potential causes of which would deserve more investigations.…”

A taxonomic revision of Campanula L. subgenus Sicyocodon (Feer) Damboldt and subgenus Megalocalyx Damboldt (Campanulaceae)

“…On the other hand, plants included in subgenus Megalocalyx show tubular‐campanulate or nearly rotate corollas, the style is smaller (4–15 mm long) and always included in the corolla. Some authors (Contandriopoulos, 1972, 1976, 1984; Gadella, 1966; Damboldt, 1978) suggested that Sicyocodon with its long exserted style probably holds a very isolated position in the genus, which is attributed to a different pollination syndrome related to flies, unique in the Campanulaceae (Damboldt, 1978). Plants included in the genus Campanula , and particularly those in subgen.…”