PARK, SEON-JOO*, ELISA KOROMPAI, JAVIER FRANCISCO-ORTEGA, ARNOLDO SANTOS-GUERRA, AND ROBERT JANSEN. Section of Integrative Biology, University of Texas, Austin TX 78712. - Phylogenetic relationships of Tolpis (Asteraceae: Lactuceae) based on ndhF sequence data.
Tolpis includes approximately 12-20 species distributed primarily in
Europe, Middle East, and Africa with most species (10) confined to the
Macaronesian archipelagos of the Azores, Madeira, Canary Islands, and
Cape Verde Islands. Although there has been considerable effort to
resolve generic circumscriptions and relationships among genera of the
tribe Lactuceae, much controversy still remains regarding these
taxonomic issues for Tolpis. Phylogenetic analyses of the chloroplast
encoded gene ndhF were performed using 36 species from 28 genera of
Lactuceae and outgroup taxa from the five other tribes of
Cichorioideae. The sampling included most previously suggested
generic relatives of Tolpis and seven species of Tolpis from Africa,
Europe, and Macaronesia. The ndhF phylogeny indicates that Tolpis is
not monophyletic because two continental species, T. capensis from
south-central Africa and Madagascar and T. staticifolia from central
and southeast Europe, do not occur in the strongly supported core
Tolpis clade. This result is in agreement with recent suggestions
based on macromorphology and palynology that these two species should
be excluded from Tolpis. Tolpis capensis is sister to Taraxacum and
T. staticifolia is nested within the genus Crepis. The ndhF tree also
indicates that the core Tolpis clade is an isolated lineage that is
not related to any of the previously suggested genera of Lactuceae.
Relationships among the five examined core Tolpis species are fully
resolved in the ndhF tree. The three examined island species occur in
two different clades suggesting either multiple colonizations or a
single origin and subsequent recolonization of the continent.
Resolution of the origin of the island endemics will require addtional
taxon sampling and the use of more variable molecular markers.
Key words: Asteraceae, Lactuceae, ndhF, Tolpis