KARAMAN, VESNA* and LOWELL E. URBATSCH. Louisiana State University, Department of Biological Sciences, 508 Life Science Building, Baton Rouge, LA, 70803. - Phylogenetic analysis of Boltonia (Astereae, Asteraceae) based on nr ETS and ITS sequence data.
The genus Boltonia mainly occurs in eastern North America. It
comprises five species that grow in moist to wet habitats. The genus
was previously suggested to be closely related to the Old World
Kalimeris. However, morphological data by Gu and Hoch provided
evidence that these two genera were not closely allied. DNA sequence
data by Noyes and Rieseberg supported Boltonia's close
affiliation with New World Symphyotrichum, Batopilasia
byei (as Erigeron byei), and genera of Machaerantherinae.
In our phylogeny based on ETS and ITS sequence data with Aster
amellus as the outgroup Kalimeris appears basal, while
Boltonia is the most derived lineage. Batopilasia and
Chloracantha are sisters and this clade in turn is sister to
Boltonia, thus supporting Nesom's most recent suggestion of
relationship; Symphyotrichum in turn is sister to this clade.
Furthermore, our sequence data resolves three lineages within
Boltonia that conflict with current taxonomic hypotheses. B.
asteroides var. latisquama, and B. asteroides var.
recognita are separated from B. asteroides var.
asteroides and are placed in a separate clade together with
B. decurrens and B. apalachicolensis.
Key words: Astereae, Boltonia, external transcribed spacer region (ETS), internal transcribed spacer region (ITS), molecular data