BERRY, PAUL E.*, AUSTIN R. MAST, WILLIAM H. HAHN, AND KENNETH J. SYTSMA. Department of Botany, University of Wisconsin, Madison, WI 53706. - Evaluation of sectional delimitations in Fuchsia (Onagraceae) using chloroplast and nuclear DNA sequence data.
Recent morphologically-based treatments of Fuchsia (Onagraceae)
recognize 105 species in 11 sections. This study examines the
monophyly of the sections and intersectional relationships using
sequence data from the ITS region of nuclear ribosomal DNA and two
chloroplast DNA regions (the rpl16 intron and trnL/F spacer). The
study uses 45 accessions representing 35 Fuchsia species in all
11 sections and four species in two outgroup genera, Circaea
and Hauya. Relationships common to the nrDNA and cpDNA results
include the following: Monotypic section Pachyrrhiza from Peru
is sister to (nr), or nested in (cp), the large and generally
monophyletic Andean section Fuchsia. Sections Jimenezia
and Schufia are sister to the third small-flowered Central
American section Encliandra (cp) or to members of the
large-flowered Central American section Ellobium (nr). Coastal
Chilean section Kierschlegeria is sister to south temperate
Andean and southeastern Brazilian section Quelusia. The
remaining sections (Andean Hemsleyella, Central American
Ellobium, and South Pacific Skinnera and
Procumbentes) are monophyletic (except Ellobium in nr
results), but their relationships to other sections are not strongly
supported with the character sampling. The small flowered Fuchsia
verrucosa from northern South America clearly does not belong in
section Fuchsia, appearing sister to section Encliandra
(cp) or sister to section Hemsleyella (nr). The Hispaniolan
Fuchsia triphylla is nested in the mainly Andean section
Fuchsia (nr), but in the cp results it is sister to the
apetalous section Hemsleyella. With these data and additional
molecular and morphological sampling, we hope to obtain greater basal
resolution and address biogeographical questions such as: 1) Are the
two South Pacific sections sister to the nine American sections?, 2)
Are sections Quelusia and Kierschlegeria from southern
South America basalmost among the American species?, and 3) what are
the closest relatives to the Central American sections?
Key words: biogeography, Fuchsia, molecular systematics, sectional relationships