Molecular phylogeny of Diplolepis (Apocynaceae-Asclepiadoideae) and allied genera: taxonomic and nomenclatural implications. Taxon 60: 638-648.

HECHEM, V., ; CALVIÑO, C. I. ; EZCURRA, C.

TAXON

INT ASSOC PLANT TAXONOMY

Año: 2011 vol. 60 p. 638 - 648

0040-0262

Diplolepis, a genus from southern South America traditionally considered monotypic, has recently been shown frommolecular data to include a few species that form a monophyletic group at the base of the MOG clade of Asclepiadoideae(Apocynaceae). The species transferred to Diplolepis include plants from temperate South America mostly described underthe generic name ?Cynanchum?. Phylogenetic analyses of cpDNA trnT-trnF and rps16 sequences of 51 accessions of Asclepiadaceaeusing maximum parsimony and Bayesian inference methods show that all ?Cynanchum? from southern Argentinaand Chile (except C. atacamense), Tweedia australis and Diplolepis form a well-supported monophyletic group. Within thisgroup, three clades are recognized: two morphologically homogeneous groups from South Andean forests and high elevationareas, and a more diverse group in flower and leaf morphology from southern South American desert and semidesert areas.The phylogenetic position of C. atacamense is equivocal but the species is transferred to Diplolepis based on morphologicaland biogeographical coherence. The morphological, geographical and environmental characteristics of the three recognizedclades of Diplolepis are discussed and eight nomenclatural changes are proposed.