Beschreibung:
<jats:p><jats:italic><jats:styled-content style="fixed-case">C</jats:styled-content>alligrapha</jats:italic> (<jats:styled-content style="fixed-case">C</jats:styled-content>oleoptera: <jats:styled-content style="fixed-case">C</jats:styled-content>hrysomelidae) is a genus with species present in most of the <jats:styled-content style="fixed-case">A</jats:styled-content>merican continent, from the <jats:styled-content style="fixed-case">A</jats:styled-content>rctic polar circle to the <jats:styled-content style="fixed-case">P</jats:styled-content>ampas in <jats:styled-content style="fixed-case">A</jats:styled-content>rgentina. In its current concept, the genus comprises some 80 species, but the diagnosis of the genus is problematic, based on a combination of potentially symplesiomorphic character states. In this study, we investigate the largest taxonomic sample of <jats:italic><jats:styled-content style="fixed-case">C</jats:styled-content>alligrapha</jats:italic> diversity to date (43 species) using a phylogenetic perspective based on more than 6000 molecular characters from eight genes (four mitochondrial and four nuclear) for a systematic evaluation of the genus. The analyses also include thirteen species in the closely related <jats:italic><jats:styled-content style="fixed-case">Z</jats:styled-content>ygospila</jats:italic> (currently a subgenus of <jats:italic><jats:styled-content style="fixed-case">Z</jats:styled-content>ygogramma</jats:italic>) to assist the systematic delimitation of <jats:italic><jats:styled-content style="fixed-case">C</jats:styled-content>alligrapha</jats:italic>. Partitioned and total evidence phylogenetic trees were additionally used for molecular clock analyses and dating based on standard mt<jats:styled-content style="fixed-case">DNA</jats:styled-content> evolutionary rates, and for likelihood‐based inference of ancestral areas. <jats:italic><jats:styled-content style="fixed-case">C</jats:styled-content>alligrapha</jats:italic> and <jats:italic><jats:styled-content style="fixed-case">Z</jats:styled-content>ygospila</jats:italic> are reciprocally paraphyletic, and our interpretation of taxonomic stability merges both taxa into a larger genus <jats:italic><jats:styled-content style="fixed-case">C</jats:styled-content>alligrapha</jats:italic> which plausibly originated in the dry steppes of southern <jats:styled-content style="fixed-case">N</jats:styled-content>orth <jats:styled-content style="fixed-case">A</jats:styled-content>merica in the <jats:styled-content style="fixed-case">L</jats:styled-content>ate <jats:styled-content style="fixed-case">M</jats:styled-content>iocene. The genus includes a minimum of five strongly supported lineages which initially diversified in the <jats:styled-content style="fixed-case">P</jats:styled-content>liocene, fully congruent with expectations from morphology, but of uncertain mutual relationships. Only two of these lineages dispersed to <jats:styled-content style="fixed-case">S</jats:styled-content>outh <jats:styled-content style="fixed-case">A</jats:styled-content>merica: the group of <jats:italic><jats:styled-content style="fixed-case">C</jats:styled-content>. polyspila</jats:italic> right at the time of the final closure of the <jats:styled-content style="fixed-case">I</jats:styled-content>sthmus of <jats:styled-content style="fixed-case">P</jats:styled-content>anama in the <jats:styled-content style="fixed-case">E</jats:styled-content>arly <jats:styled-content style="fixed-case">P</jats:styled-content>liocene and the group of <jats:italic><jats:styled-content style="fixed-case">C</jats:styled-content>. argus</jats:italic> only in recent times, well in the <jats:styled-content style="fixed-case">P</jats:styled-content>leistocene. The most species‐rich lineage of <jats:italic><jats:styled-content style="fixed-case">C</jats:styled-content>alligrapha</jats:italic>, associated to trees and shrubs typical of riverine and lacustrine environments (as opposed to herbaceous steppe plants, generally <jats:styled-content style="fixed-case">M</jats:styled-content>alvaceae and <jats:styled-content style="fixed-case">A</jats:styled-content>steraceae, for most other groups) diversified and spread in <jats:styled-content style="fixed-case">N</jats:styled-content>orth <jats:styled-content style="fixed-case">A</jats:styled-content>merica in the <jats:styled-content style="fixed-case">L</jats:styled-content>ate <jats:styled-content style="fixed-case">P</jats:styled-content>liocene. The ecological shift to a stable habitat spreading in the continent due to climate change is hypothesized as one possible explanation for the evolutionary success of this group.</jats:p>